xref: /petsc/src/ts/impls/rosw/rosw.c (revision 3d5a8a6af04c38a7eb23d2a01da917c06b399402)
1e27a552bSJed Brown /*
261692a83SJed Brown   Code for timestepping with Rosenbrock W methods
3e27a552bSJed Brown 
4e27a552bSJed Brown   Notes:
5e27a552bSJed Brown   The general system is written as
6e27a552bSJed Brown 
7f9c1d6abSBarry Smith   F(t,U,Udot) = G(t,U)
8e27a552bSJed Brown 
9f9c1d6abSBarry Smith   where F represents the stiff part of the physics and G represents the non-stiff part.
10f9c1d6abSBarry Smith   This method is designed to be linearly implicit on F and can use an approximate and lagged Jacobian.
11e27a552bSJed Brown 
12e27a552bSJed Brown */
13af0996ceSBarry Smith #include <petsc/private/tsimpl.h>                /*I   "petscts.h"   I*/
141e25c274SJed Brown #include <petscdm.h>
15e27a552bSJed Brown 
16af0996ceSBarry Smith #include <petsc/private/kernels/blockinvert.h>
1761692a83SJed Brown 
1819fd82e9SBarry Smith static TSRosWType TSRosWDefault = TSROSWRA34PW2;
19e27a552bSJed Brown static PetscBool  TSRosWRegisterAllCalled;
20e27a552bSJed Brown static PetscBool  TSRosWPackageInitialized;
21e27a552bSJed Brown 
2261692a83SJed Brown typedef struct _RosWTableau *RosWTableau;
2361692a83SJed Brown struct _RosWTableau {
24e27a552bSJed Brown   char      *name;
25e27a552bSJed Brown   PetscInt  order;              /* Classical approximation order of the method */
26e27a552bSJed Brown   PetscInt  s;                  /* Number of stages */
27f4aed992SEmil Constantinescu   PetscInt  pinterp;            /* Interpolation order */
2861692a83SJed Brown   PetscReal *A;                 /* Propagation table, strictly lower triangular */
2961692a83SJed Brown   PetscReal *Gamma;             /* Stage table, lower triangular with nonzero diagonal */
30c17803e7SJed Brown   PetscBool *GammaZeroDiag;     /* Diagonal entries that are zero in stage table Gamma, vector indicating explicit statages */
3143b21953SEmil Constantinescu   PetscReal *GammaExplicitCorr; /* Coefficients for correction terms needed for explicit stages in transformed variables*/
3261692a83SJed Brown   PetscReal *b;                 /* Step completion table */
33fe7e6d57SJed Brown   PetscReal *bembed;            /* Step completion table for embedded method of order one less */
3461692a83SJed Brown   PetscReal *ASum;              /* Row sum of A */
3561692a83SJed Brown   PetscReal *GammaSum;          /* Row sum of Gamma, only needed for non-autonomous systems */
3661692a83SJed Brown   PetscReal *At;                /* Propagation table in transformed variables */
3761692a83SJed Brown   PetscReal *bt;                /* Step completion table in transformed variables */
38fe7e6d57SJed Brown   PetscReal *bembedt;           /* Step completion table of order one less in transformed variables */
3961692a83SJed Brown   PetscReal *GammaInv;          /* Inverse of Gamma, used for transformed variables */
408d59e960SJed Brown   PetscReal ccfl;               /* Placeholder for CFL coefficient relative to forward Euler */
413ca35412SEmil Constantinescu   PetscReal *binterpt;          /* Dense output formula */
42e27a552bSJed Brown };
4361692a83SJed Brown typedef struct _RosWTableauLink *RosWTableauLink;
4461692a83SJed Brown struct _RosWTableauLink {
4561692a83SJed Brown   struct _RosWTableau tab;
4661692a83SJed Brown   RosWTableauLink     next;
47e27a552bSJed Brown };
4861692a83SJed Brown static RosWTableauLink RosWTableauList;
49e27a552bSJed Brown 
50e27a552bSJed Brown typedef struct {
5161692a83SJed Brown   RosWTableau  tableau;
5261692a83SJed Brown   Vec          *Y;               /* States computed during the step, used to complete the step */
53e27a552bSJed Brown   Vec          Ydot;             /* Work vector holding Ydot during residual evaluation */
5461692a83SJed Brown   Vec          Ystage;           /* Work vector for the state value at each stage */
5561692a83SJed Brown   Vec          Zdot;             /* Ydot = Zdot + shift*Y */
5661692a83SJed Brown   Vec          Zstage;           /* Y = Zstage + Y */
57be5899b3SLisandro Dalcin   Vec          vec_sol_prev;     /* Solution from the previous step (used for interpolation and rollback)*/
581c3436cfSJed Brown   PetscScalar  *work;            /* Scalar work space of length number of stages, used to prepare VecMAXPY() */
59b296d7d5SJed Brown   PetscReal    scoeff;           /* shift = scoeff/dt */
60e27a552bSJed Brown   PetscReal    stage_time;
61c17803e7SJed Brown   PetscReal    stage_explicit;     /* Flag indicates that the current stage is explicit */
6261692a83SJed Brown   PetscBool    recompute_jacobian; /* Recompute the Jacobian at each stage, default is to freeze the Jacobian at the start of each step */
63108c343cSJed Brown   TSStepStatus status;
64e27a552bSJed Brown } TS_RosW;
65e27a552bSJed Brown 
66fe7e6d57SJed Brown /*MC
673606a31eSEmil Constantinescu      TSROSWTHETA1 - One stage first order L-stable Rosenbrock-W scheme (aka theta method).
683606a31eSEmil Constantinescu 
693606a31eSEmil Constantinescu      Only an approximate Jacobian is needed.
703606a31eSEmil Constantinescu 
713606a31eSEmil Constantinescu      Level: intermediate
723606a31eSEmil Constantinescu 
733606a31eSEmil Constantinescu .seealso: TSROSW
743606a31eSEmil Constantinescu M*/
753606a31eSEmil Constantinescu 
763606a31eSEmil Constantinescu /*MC
773606a31eSEmil Constantinescu      TSROSWTHETA2 - One stage second order A-stable Rosenbrock-W scheme (aka theta method).
783606a31eSEmil Constantinescu 
793606a31eSEmil Constantinescu      Only an approximate Jacobian is needed.
803606a31eSEmil Constantinescu 
813606a31eSEmil Constantinescu      Level: intermediate
823606a31eSEmil Constantinescu 
833606a31eSEmil Constantinescu .seealso: TSROSW
843606a31eSEmil Constantinescu M*/
853606a31eSEmil Constantinescu 
863606a31eSEmil Constantinescu /*MC
87fe7e6d57SJed Brown      TSROSW2M - Two stage second order L-stable Rosenbrock-W scheme.
88fe7e6d57SJed Brown 
89fe7e6d57SJed Brown      Only an approximate Jacobian is needed. By default, it is only recomputed once per step. This method is a reflection of TSROSW2P.
90fe7e6d57SJed Brown 
91fe7e6d57SJed Brown      Level: intermediate
92fe7e6d57SJed Brown 
93fe7e6d57SJed Brown .seealso: TSROSW
94fe7e6d57SJed Brown M*/
95fe7e6d57SJed Brown 
96fe7e6d57SJed Brown /*MC
97fe7e6d57SJed Brown      TSROSW2P - Two stage second order L-stable Rosenbrock-W scheme.
98fe7e6d57SJed Brown 
99fe7e6d57SJed Brown      Only an approximate Jacobian is needed. By default, it is only recomputed once per step. This method is a reflection of TSROSW2M.
100fe7e6d57SJed Brown 
101fe7e6d57SJed Brown      Level: intermediate
102fe7e6d57SJed Brown 
103fe7e6d57SJed Brown .seealso: TSROSW
104fe7e6d57SJed Brown M*/
105fe7e6d57SJed Brown 
106fe7e6d57SJed Brown /*MC
107fe7e6d57SJed Brown      TSROSWRA3PW - Three stage third order Rosenbrock-W scheme for PDAE of index 1.
108fe7e6d57SJed Brown 
109fe7e6d57SJed Brown      Only an approximate Jacobian is needed. By default, it is only recomputed once per step.
110fe7e6d57SJed Brown 
111fe7e6d57SJed Brown      This is strongly A-stable with R(infty) = 0.73. The embedded method of order 2 is strongly A-stable with R(infty) = 0.73.
112fe7e6d57SJed Brown 
113fe7e6d57SJed Brown      References:
11496a0c994SBarry Smith .  1. -   Rang and Angermann, New Rosenbrock W methods of order 3 for partial differential algebraic equations of index 1, 2005.
115fe7e6d57SJed Brown 
116fe7e6d57SJed Brown      Level: intermediate
117fe7e6d57SJed Brown 
118fe7e6d57SJed Brown .seealso: TSROSW
119fe7e6d57SJed Brown M*/
120fe7e6d57SJed Brown 
121fe7e6d57SJed Brown /*MC
122fe7e6d57SJed Brown      TSROSWRA34PW2 - Four stage third order L-stable Rosenbrock-W scheme for PDAE of index 1.
123fe7e6d57SJed Brown 
124fe7e6d57SJed Brown      Only an approximate Jacobian is needed. By default, it is only recomputed once per step.
125fe7e6d57SJed Brown 
126fe7e6d57SJed Brown      This is strongly A-stable with R(infty) = 0. The embedded method of order 2 is strongly A-stable with R(infty) = 0.48.
127fe7e6d57SJed Brown 
128fe7e6d57SJed Brown      References:
12996a0c994SBarry Smith .  1. -   Rang and Angermann, New Rosenbrock W methods of order 3 for partial differential algebraic equations of index 1, 2005.
130fe7e6d57SJed Brown 
131fe7e6d57SJed Brown      Level: intermediate
132fe7e6d57SJed Brown 
133fe7e6d57SJed Brown .seealso: TSROSW
134fe7e6d57SJed Brown M*/
135fe7e6d57SJed Brown 
136ef3c5b88SJed Brown /*MC
137ef3c5b88SJed Brown      TSROSWRODAS3 - Four stage third order L-stable Rosenbrock scheme
138ef3c5b88SJed Brown 
139ef3c5b88SJed Brown      By default, the Jacobian is only recomputed once per step.
140ef3c5b88SJed Brown 
141ef3c5b88SJed Brown      Both the third order and embedded second order methods are stiffly accurate and L-stable.
142ef3c5b88SJed Brown 
143ef3c5b88SJed Brown      References:
14496a0c994SBarry Smith .  1. -   Sandu et al, Benchmarking stiff ODE solvers for atmospheric chemistry problems II, Rosenbrock solvers, 1997.
145ef3c5b88SJed Brown 
146ef3c5b88SJed Brown      Level: intermediate
147ef3c5b88SJed Brown 
148ef3c5b88SJed Brown .seealso: TSROSW, TSROSWSANDU3
149ef3c5b88SJed Brown M*/
150ef3c5b88SJed Brown 
151ef3c5b88SJed Brown /*MC
152ef3c5b88SJed Brown      TSROSWSANDU3 - Three stage third order L-stable Rosenbrock scheme
153ef3c5b88SJed Brown 
154ef3c5b88SJed Brown      By default, the Jacobian is only recomputed once per step.
155ef3c5b88SJed Brown 
156ef3c5b88SJed Brown      The third order method is L-stable, but not stiffly accurate.
157ef3c5b88SJed Brown      The second order embedded method is strongly A-stable with R(infty) = 0.5.
158ef3c5b88SJed Brown      The internal stages are L-stable.
159ef3c5b88SJed Brown      This method is called ROS3 in the paper.
160ef3c5b88SJed Brown 
161ef3c5b88SJed Brown      References:
16296a0c994SBarry Smith .  1. -   Sandu et al, Benchmarking stiff ODE solvers for atmospheric chemistry problems II, Rosenbrock solvers, 1997.
163ef3c5b88SJed Brown 
164ef3c5b88SJed Brown      Level: intermediate
165ef3c5b88SJed Brown 
166ef3c5b88SJed Brown .seealso: TSROSW, TSROSWRODAS3
167ef3c5b88SJed Brown M*/
168ef3c5b88SJed Brown 
169961f28d0SJed Brown /*MC
170961f28d0SJed Brown      TSROSWASSP3P3S1C - A-stable Rosenbrock-W method with SSP explicit part, third order, three stages
171961f28d0SJed Brown 
172961f28d0SJed Brown      By default, the Jacobian is only recomputed once per step.
173961f28d0SJed Brown 
174961f28d0SJed Brown      A-stable SPP explicit order 3, 3 stages, CFL 1 (eff = 1/3)
175961f28d0SJed Brown 
176961f28d0SJed Brown      References:
17796a0c994SBarry Smith .     Emil Constantinescu
178961f28d0SJed Brown 
179961f28d0SJed Brown      Level: intermediate
180961f28d0SJed Brown 
18143b21953SEmil Constantinescu .seealso: TSROSW, TSROSWLASSP3P4S2C, TSROSWLLSSP3P4S2C, SSP
182961f28d0SJed Brown M*/
183961f28d0SJed Brown 
184961f28d0SJed Brown /*MC
185998eb97aSJed Brown      TSROSWLASSP3P4S2C - L-stable Rosenbrock-W method with SSP explicit part, third order, four stages
186961f28d0SJed Brown 
187961f28d0SJed Brown      By default, the Jacobian is only recomputed once per step.
188961f28d0SJed Brown 
189961f28d0SJed Brown      L-stable (A-stable embedded) SPP explicit order 3, 4 stages, CFL 2 (eff = 1/2)
190961f28d0SJed Brown 
191961f28d0SJed Brown      References:
19296a0c994SBarry Smith .     Emil Constantinescu
193961f28d0SJed Brown 
194961f28d0SJed Brown      Level: intermediate
195961f28d0SJed Brown 
19643b21953SEmil Constantinescu .seealso: TSROSW, TSROSWASSP3P3S1C, TSROSWLLSSP3P4S2C, TSSSP
197961f28d0SJed Brown M*/
198961f28d0SJed Brown 
199961f28d0SJed Brown /*MC
200998eb97aSJed Brown      TSROSWLLSSP3P4S2C - L-stable Rosenbrock-W method with SSP explicit part, third order, four stages
201961f28d0SJed Brown 
202961f28d0SJed Brown      By default, the Jacobian is only recomputed once per step.
203961f28d0SJed Brown 
204961f28d0SJed Brown      L-stable (L-stable embedded) SPP explicit order 3, 4 stages, CFL 2 (eff = 1/2)
205961f28d0SJed Brown 
206961f28d0SJed Brown      References:
20796a0c994SBarry Smith .     Emil Constantinescu
208961f28d0SJed Brown 
209961f28d0SJed Brown      Level: intermediate
210961f28d0SJed Brown 
211961f28d0SJed Brown .seealso: TSROSW, TSROSWASSP3P3S1C, TSROSWLASSP3P4S2C, TSSSP
212961f28d0SJed Brown M*/
213961f28d0SJed Brown 
21442faf41dSJed Brown /*MC
21542faf41dSJed Brown      TSROSWGRK4T - four stage, fourth order Rosenbrock (not W) method from Kaps and Rentrop
21642faf41dSJed Brown 
21742faf41dSJed Brown      By default, the Jacobian is only recomputed once per step.
21842faf41dSJed Brown 
21942faf41dSJed Brown      A(89.3 degrees)-stable, |R(infty)| = 0.454.
22042faf41dSJed Brown 
22142faf41dSJed Brown      This method does not provide a dense output formula.
22242faf41dSJed Brown 
22342faf41dSJed Brown      References:
22496a0c994SBarry Smith +   1. -  Kaps and Rentrop, Generalized Runge Kutta methods of order four with stepsize control for stiff ordinary differential equations, 1979.
22596a0c994SBarry Smith -   2. -  Hairer and Wanner, Solving Ordinary Differential Equations II, Section 4 Table 7.2.
22642faf41dSJed Brown 
22742faf41dSJed Brown      Hairer's code ros4.f
22842faf41dSJed Brown 
22942faf41dSJed Brown      Level: intermediate
23042faf41dSJed Brown 
23142faf41dSJed Brown .seealso: TSROSW, TSROSWSHAMP4, TSROSWVELDD4, TSROSW4L
23242faf41dSJed Brown M*/
23342faf41dSJed Brown 
23442faf41dSJed Brown /*MC
23542faf41dSJed Brown      TSROSWSHAMP4 - four stage, fourth order Rosenbrock (not W) method from Shampine
23642faf41dSJed Brown 
23742faf41dSJed Brown      By default, the Jacobian is only recomputed once per step.
23842faf41dSJed Brown 
23942faf41dSJed Brown      A-stable, |R(infty)| = 1/3.
24042faf41dSJed Brown 
24142faf41dSJed Brown      This method does not provide a dense output formula.
24242faf41dSJed Brown 
24342faf41dSJed Brown      References:
24496a0c994SBarry Smith +   1. -  Shampine, Implementation of Rosenbrock methods, 1982.
24596a0c994SBarry Smith -   2. -  Hairer and Wanner, Solving Ordinary Differential Equations II, Section 4 Table 7.2.
24642faf41dSJed Brown 
24742faf41dSJed Brown      Hairer's code ros4.f
24842faf41dSJed Brown 
24942faf41dSJed Brown      Level: intermediate
25042faf41dSJed Brown 
25142faf41dSJed Brown .seealso: TSROSW, TSROSWGRK4T, TSROSWVELDD4, TSROSW4L
25242faf41dSJed Brown M*/
25342faf41dSJed Brown 
25442faf41dSJed Brown /*MC
25542faf41dSJed Brown      TSROSWVELDD4 - four stage, fourth order Rosenbrock (not W) method from van Veldhuizen
25642faf41dSJed Brown 
25742faf41dSJed Brown      By default, the Jacobian is only recomputed once per step.
25842faf41dSJed Brown 
25942faf41dSJed Brown      A(89.5 degrees)-stable, |R(infty)| = 0.24.
26042faf41dSJed Brown 
26142faf41dSJed Brown      This method does not provide a dense output formula.
26242faf41dSJed Brown 
26342faf41dSJed Brown      References:
26496a0c994SBarry Smith +   1. -  van Veldhuizen, D stability and Kaps Rentrop methods, 1984.
26596a0c994SBarry Smith -   2. -  Hairer and Wanner, Solving Ordinary Differential Equations II, Section 4 Table 7.2.
26642faf41dSJed Brown 
26742faf41dSJed Brown      Hairer's code ros4.f
26842faf41dSJed Brown 
26942faf41dSJed Brown      Level: intermediate
27042faf41dSJed Brown 
27142faf41dSJed Brown .seealso: TSROSW, TSROSWGRK4T, TSROSWSHAMP4, TSROSW4L
27242faf41dSJed Brown M*/
27342faf41dSJed Brown 
27442faf41dSJed Brown /*MC
27542faf41dSJed Brown      TSROSW4L - four stage, fourth order Rosenbrock (not W) method
27642faf41dSJed Brown 
27742faf41dSJed Brown      By default, the Jacobian is only recomputed once per step.
27842faf41dSJed Brown 
27942faf41dSJed Brown      A-stable and L-stable
28042faf41dSJed Brown 
28142faf41dSJed Brown      This method does not provide a dense output formula.
28242faf41dSJed Brown 
28342faf41dSJed Brown      References:
28496a0c994SBarry Smith .  1. -   Hairer and Wanner, Solving Ordinary Differential Equations II, Section 4 Table 7.2.
28542faf41dSJed Brown 
28642faf41dSJed Brown      Hairer's code ros4.f
28742faf41dSJed Brown 
28842faf41dSJed Brown      Level: intermediate
28942faf41dSJed Brown 
29042faf41dSJed Brown .seealso: TSROSW, TSROSWGRK4T, TSROSWSHAMP4, TSROSW4L
29142faf41dSJed Brown M*/
29242faf41dSJed Brown 
293e27a552bSJed Brown /*@C
294be5899b3SLisandro Dalcin   TSRosWRegisterAll - Registers all of the Rosenbrock-W methods in TSRosW
295e27a552bSJed Brown 
296e27a552bSJed Brown   Not Collective, but should be called by all processes which will need the schemes to be registered
297e27a552bSJed Brown 
298e27a552bSJed Brown   Level: advanced
299e27a552bSJed Brown 
300e27a552bSJed Brown .seealso:  TSRosWRegisterDestroy()
301e27a552bSJed Brown @*/
302e27a552bSJed Brown PetscErrorCode TSRosWRegisterAll(void)
303e27a552bSJed Brown {
304e27a552bSJed Brown   PetscErrorCode ierr;
305e27a552bSJed Brown 
306e27a552bSJed Brown   PetscFunctionBegin;
307e27a552bSJed Brown   if (TSRosWRegisterAllCalled) PetscFunctionReturn(0);
308e27a552bSJed Brown   TSRosWRegisterAllCalled = PETSC_TRUE;
309e27a552bSJed Brown 
310e27a552bSJed Brown   {
311bbd56ea5SKarl Rupp     const PetscReal A = 0;
312bbd56ea5SKarl Rupp     const PetscReal Gamma = 1;
313bbd56ea5SKarl Rupp     const PetscReal b = 1;
314bbd56ea5SKarl Rupp     const PetscReal binterpt=1;
3151f80e275SEmil Constantinescu 
3160298fd71SBarry Smith     ierr = TSRosWRegister(TSROSWTHETA1,1,1,&A,&Gamma,&b,NULL,1,&binterpt);CHKERRQ(ierr);
3173606a31eSEmil Constantinescu   }
3183606a31eSEmil Constantinescu 
3193606a31eSEmil Constantinescu   {
320bbd56ea5SKarl Rupp     const PetscReal A = 0;
321bbd56ea5SKarl Rupp     const PetscReal Gamma = 0.5;
322bbd56ea5SKarl Rupp     const PetscReal b = 1;
323bbd56ea5SKarl Rupp     const PetscReal binterpt=1;
324bbd56ea5SKarl Rupp 
3250298fd71SBarry Smith     ierr = TSRosWRegister(TSROSWTHETA2,2,1,&A,&Gamma,&b,NULL,1,&binterpt);CHKERRQ(ierr);
3263606a31eSEmil Constantinescu   }
3273606a31eSEmil Constantinescu 
3283606a31eSEmil Constantinescu   {
329da80777bSKarl Rupp     /*const PetscReal g = 1. + 1./PetscSqrtReal(2.0);   Direct evaluation: 1.707106781186547524401. Used for setting up arrays of values known at compile time below. */
330e27a552bSJed Brown     const PetscReal
33161692a83SJed Brown       A[2][2]     = {{0,0}, {1.,0}},
332da80777bSKarl Rupp       Gamma[2][2] = {{1.707106781186547524401,0}, {-2.*1.707106781186547524401,1.707106781186547524401}},
3331c3436cfSJed Brown       b[2]        = {0.5,0.5},
3341c3436cfSJed Brown       b1[2]       = {1.0,0.0};
3351f80e275SEmil Constantinescu     PetscReal binterpt[2][2];
336da80777bSKarl Rupp     binterpt[0][0] = 1.707106781186547524401 - 1.0;
337da80777bSKarl Rupp     binterpt[1][0] = 2.0 - 1.707106781186547524401;
338da80777bSKarl Rupp     binterpt[0][1] = 1.707106781186547524401 - 1.5;
339da80777bSKarl Rupp     binterpt[1][1] = 1.5 - 1.707106781186547524401;
340bbd56ea5SKarl Rupp 
3411f80e275SEmil Constantinescu     ierr = TSRosWRegister(TSROSW2P,2,2,&A[0][0],&Gamma[0][0],b,b1,2,&binterpt[0][0]);CHKERRQ(ierr);
342e27a552bSJed Brown   }
343e27a552bSJed Brown   {
344da80777bSKarl Rupp     /*const PetscReal g = 1. - 1./PetscSqrtReal(2.0);   Direct evaluation: 0.2928932188134524755992. Used for setting up arrays of values known at compile time below. */
345e27a552bSJed Brown     const PetscReal
34661692a83SJed Brown       A[2][2]     = {{0,0}, {1.,0}},
347da80777bSKarl Rupp       Gamma[2][2] = {{0.2928932188134524755992,0}, {-2.*0.2928932188134524755992,0.2928932188134524755992}},
3481c3436cfSJed Brown       b[2]        = {0.5,0.5},
3491c3436cfSJed Brown       b1[2]       = {1.0,0.0};
3501f80e275SEmil Constantinescu     PetscReal binterpt[2][2];
351da80777bSKarl Rupp     binterpt[0][0] = 0.2928932188134524755992 - 1.0;
352da80777bSKarl Rupp     binterpt[1][0] = 2.0 - 0.2928932188134524755992;
353da80777bSKarl Rupp     binterpt[0][1] = 0.2928932188134524755992 - 1.5;
354da80777bSKarl Rupp     binterpt[1][1] = 1.5 - 0.2928932188134524755992;
355bbd56ea5SKarl Rupp 
3561f80e275SEmil Constantinescu     ierr = TSRosWRegister(TSROSW2M,2,2,&A[0][0],&Gamma[0][0],b,b1,2,&binterpt[0][0]);CHKERRQ(ierr);
357fe7e6d57SJed Brown   }
358fe7e6d57SJed Brown   {
359da80777bSKarl Rupp     /*const PetscReal g = 7.8867513459481287e-01; Directly written in-place below */
3601f80e275SEmil Constantinescu     PetscReal binterpt[3][2];
361fe7e6d57SJed Brown     const PetscReal
362fe7e6d57SJed Brown       A[3][3] = {{0,0,0},
363fe7e6d57SJed Brown                  {1.5773502691896257e+00,0,0},
364fe7e6d57SJed Brown                  {0.5,0,0}},
365da80777bSKarl Rupp       Gamma[3][3] = {{7.8867513459481287e-01,0,0},
366da80777bSKarl Rupp                      {-1.5773502691896257e+00,7.8867513459481287e-01,0},
367da80777bSKarl Rupp                      {-6.7075317547305480e-01,-1.7075317547305482e-01,7.8867513459481287e-01}},
368fe7e6d57SJed Brown       b[3]  = {1.0566243270259355e-01,4.9038105676657971e-02,8.4529946162074843e-01},
369fe7e6d57SJed Brown       b2[3] = {-1.7863279495408180e-01,1./3.,8.4529946162074843e-01};
3701f80e275SEmil Constantinescu 
3711f80e275SEmil Constantinescu       binterpt[0][0] = -0.8094010767585034;
3721f80e275SEmil Constantinescu       binterpt[1][0] = -0.5;
3731f80e275SEmil Constantinescu       binterpt[2][0] = 2.3094010767585034;
3741f80e275SEmil Constantinescu       binterpt[0][1] = 0.9641016151377548;
3751f80e275SEmil Constantinescu       binterpt[1][1] = 0.5;
3761f80e275SEmil Constantinescu       binterpt[2][1] = -1.4641016151377548;
377bbd56ea5SKarl Rupp 
3781f80e275SEmil Constantinescu       ierr = TSRosWRegister(TSROSWRA3PW,3,3,&A[0][0],&Gamma[0][0],b,b2,2,&binterpt[0][0]);CHKERRQ(ierr);
379fe7e6d57SJed Brown   }
380fe7e6d57SJed Brown   {
3813ca35412SEmil Constantinescu     PetscReal  binterpt[4][3];
382da80777bSKarl Rupp     /*const PetscReal g = 4.3586652150845900e-01; Directly written in-place below */
383fe7e6d57SJed Brown     const PetscReal
384fe7e6d57SJed Brown       A[4][4] = {{0,0,0,0},
385fe7e6d57SJed Brown                  {8.7173304301691801e-01,0,0,0},
386fe7e6d57SJed Brown                  {8.4457060015369423e-01,-1.1299064236484185e-01,0,0},
387fe7e6d57SJed Brown                  {0,0,1.,0}},
388da80777bSKarl Rupp       Gamma[4][4] = {{4.3586652150845900e-01,0,0,0},
389da80777bSKarl Rupp                      {-8.7173304301691801e-01,4.3586652150845900e-01,0,0},
390da80777bSKarl Rupp                      {-9.0338057013044082e-01,5.4180672388095326e-02,4.3586652150845900e-01,0},
391da80777bSKarl Rupp                      {2.4212380706095346e-01,-1.2232505839045147e+00,5.4526025533510214e-01,4.3586652150845900e-01}},
392fe7e6d57SJed Brown       b[4]  = {2.4212380706095346e-01,-1.2232505839045147e+00,1.5452602553351020e+00,4.3586652150845900e-01},
3933ca35412SEmil Constantinescu       b2[4] = {3.7810903145819369e-01,-9.6042292212423178e-02,5.0000000000000000e-01,2.1793326075422950e-01};
3943ca35412SEmil Constantinescu 
3953ca35412SEmil Constantinescu     binterpt[0][0]=1.0564298455794094;
3963ca35412SEmil Constantinescu     binterpt[1][0]=2.296429974281067;
3973ca35412SEmil Constantinescu     binterpt[2][0]=-1.307599564525376;
3983ca35412SEmil Constantinescu     binterpt[3][0]=-1.045260255335102;
3993ca35412SEmil Constantinescu     binterpt[0][1]=-1.3864882699759573;
4003ca35412SEmil Constantinescu     binterpt[1][1]=-8.262611700275677;
4013ca35412SEmil Constantinescu     binterpt[2][1]=7.250979895056055;
4023ca35412SEmil Constantinescu     binterpt[3][1]=2.398120075195581;
4033ca35412SEmil Constantinescu     binterpt[0][2]=0.5721822314575016;
4043ca35412SEmil Constantinescu     binterpt[1][2]=4.742931142090097;
4053ca35412SEmil Constantinescu     binterpt[2][2]=-4.398120075195578;
4063ca35412SEmil Constantinescu     binterpt[3][2]=-0.9169932983520199;
4073ca35412SEmil Constantinescu 
4083ca35412SEmil Constantinescu     ierr = TSRosWRegister(TSROSWRA34PW2,3,4,&A[0][0],&Gamma[0][0],b,b2,3,&binterpt[0][0]);CHKERRQ(ierr);
409e27a552bSJed Brown   }
410ef3c5b88SJed Brown   {
411da80777bSKarl Rupp     /* const PetscReal g = 0.5;       Directly written in-place below */
412ef3c5b88SJed Brown     const PetscReal
413ef3c5b88SJed Brown       A[4][4] = {{0,0,0,0},
414ef3c5b88SJed Brown                  {0,0,0,0},
415ef3c5b88SJed Brown                  {1.,0,0,0},
416ef3c5b88SJed Brown                  {0.75,-0.25,0.5,0}},
417da80777bSKarl Rupp       Gamma[4][4] = {{0.5,0,0,0},
418da80777bSKarl Rupp                      {1.,0.5,0,0},
419da80777bSKarl Rupp                      {-0.25,-0.25,0.5,0},
420da80777bSKarl Rupp                      {1./12,1./12,-2./3,0.5}},
421ef3c5b88SJed Brown       b[4]  = {5./6,-1./6,-1./6,0.5},
422ef3c5b88SJed Brown       b2[4] = {0.75,-0.25,0.5,0};
423bbd56ea5SKarl Rupp 
4240298fd71SBarry Smith     ierr = TSRosWRegister(TSROSWRODAS3,3,4,&A[0][0],&Gamma[0][0],b,b2,0,NULL);CHKERRQ(ierr);
425ef3c5b88SJed Brown   }
426ef3c5b88SJed Brown   {
427da80777bSKarl Rupp     /*const PetscReal g = 0.43586652150845899941601945119356;       Directly written in-place below */
428ef3c5b88SJed Brown     const PetscReal
429ef3c5b88SJed Brown       A[3][3] = {{0,0,0},
430da80777bSKarl Rupp                  {0.43586652150845899941601945119356,0,0},
431da80777bSKarl Rupp                  {0.43586652150845899941601945119356,0,0}},
432da80777bSKarl Rupp       Gamma[3][3] = {{0.43586652150845899941601945119356,0,0},
433da80777bSKarl Rupp                      {-0.19294655696029095575009695436041,0.43586652150845899941601945119356,0},
434da80777bSKarl Rupp                      {0,1.74927148125794685173529749738960,0.43586652150845899941601945119356}},
435ef3c5b88SJed Brown       b[3]  = {-0.75457412385404315829818998646589,1.94100407061964420292840123379419,-0.18642994676560104463021124732829},
436ef3c5b88SJed Brown       b2[3] = {-1.53358745784149585370766523913002,2.81745131148625772213931745457622,-0.28386385364476186843165221544619};
4371f80e275SEmil Constantinescu 
4381f80e275SEmil Constantinescu     PetscReal binterpt[3][2];
4391f80e275SEmil Constantinescu     binterpt[0][0] = 3.793692883777660870425141387941;
4401f80e275SEmil Constantinescu     binterpt[1][0] = -2.918692883777660870425141387941;
4411f80e275SEmil Constantinescu     binterpt[2][0] = 0.125;
4421f80e275SEmil Constantinescu     binterpt[0][1] = -0.725741064379812106687651020584;
4431f80e275SEmil Constantinescu     binterpt[1][1] = 0.559074397713145440020984353917;
4441f80e275SEmil Constantinescu     binterpt[2][1] = 0.16666666666666666666666666666667;
4451f80e275SEmil Constantinescu 
4461f80e275SEmil Constantinescu     ierr = TSRosWRegister(TSROSWSANDU3,3,3,&A[0][0],&Gamma[0][0],b,b2,2,&binterpt[0][0]);CHKERRQ(ierr);
447ef3c5b88SJed Brown   }
448b1c69cc3SEmil Constantinescu   {
449da80777bSKarl Rupp     /*const PetscReal s3 = PetscSqrtReal(3.),g = (3.0+s3)/6.0;
450da80777bSKarl Rupp      * Direct evaluation: s3 = 1.732050807568877293527;
451da80777bSKarl Rupp      *                     g = 0.7886751345948128822546;
452da80777bSKarl Rupp      * Values are directly inserted below to ensure availability at compile time (compiler warnings otherwise...) */
453b1c69cc3SEmil Constantinescu     const PetscReal
454b1c69cc3SEmil Constantinescu       A[3][3] = {{0,0,0},
455b1c69cc3SEmil Constantinescu                  {1,0,0},
456b1c69cc3SEmil Constantinescu                  {0.25,0.25,0}},
457b1c69cc3SEmil Constantinescu       Gamma[3][3] = {{0,0,0},
458da80777bSKarl Rupp                      {(-3.0-1.732050807568877293527)/6.0,0.7886751345948128822546,0},
459da80777bSKarl Rupp                      {(-3.0-1.732050807568877293527)/24.0,(-3.0-1.732050807568877293527)/8.0,0.7886751345948128822546}},
460b1c69cc3SEmil Constantinescu       b[3]  = {1./6.,1./6.,2./3.},
461b1c69cc3SEmil Constantinescu       b2[3] = {1./4.,1./4.,1./2.};
462c0cb691aSEmil Constantinescu     PetscReal binterpt[3][2];
463da80777bSKarl Rupp 
464c0cb691aSEmil Constantinescu     binterpt[0][0]=0.089316397477040902157517886164709;
465c0cb691aSEmil Constantinescu     binterpt[1][0]=-0.91068360252295909784248211383529;
466c0cb691aSEmil Constantinescu     binterpt[2][0]=1.8213672050459181956849642276706;
467c0cb691aSEmil Constantinescu     binterpt[0][1]=0.077350269189625764509148780501957;
468c0cb691aSEmil Constantinescu     binterpt[1][1]=1.077350269189625764509148780502;
469c0cb691aSEmil Constantinescu     binterpt[2][1]=-1.1547005383792515290182975610039;
470bbd56ea5SKarl Rupp 
471c0cb691aSEmil Constantinescu     ierr = TSRosWRegister(TSROSWASSP3P3S1C,3,3,&A[0][0],&Gamma[0][0],b,b2,2,&binterpt[0][0]);CHKERRQ(ierr);
472b1c69cc3SEmil Constantinescu   }
473b1c69cc3SEmil Constantinescu 
474b1c69cc3SEmil Constantinescu   {
475b1c69cc3SEmil Constantinescu     const PetscReal
476b1c69cc3SEmil Constantinescu       A[4][4] = {{0,0,0,0},
477b1c69cc3SEmil Constantinescu                  {1./2.,0,0,0},
478b1c69cc3SEmil Constantinescu                  {1./2.,1./2.,0,0},
479b1c69cc3SEmil Constantinescu                  {1./6.,1./6.,1./6.,0}},
480b1c69cc3SEmil Constantinescu       Gamma[4][4] = {{1./2.,0,0,0},
481b1c69cc3SEmil Constantinescu                      {0.0,1./4.,0,0},
482b1c69cc3SEmil Constantinescu                      {-2.,-2./3.,2./3.,0},
483b1c69cc3SEmil Constantinescu                      {1./2.,5./36.,-2./9,0}},
484b1c69cc3SEmil Constantinescu       b[4]  = {1./6.,1./6.,1./6.,1./2.},
485b1c69cc3SEmil Constantinescu       b2[4] = {1./8.,3./4.,1./8.,0};
486c0cb691aSEmil Constantinescu     PetscReal binterpt[4][3];
487da80777bSKarl Rupp 
488c0cb691aSEmil Constantinescu     binterpt[0][0]=6.25;
489c0cb691aSEmil Constantinescu     binterpt[1][0]=-30.25;
490c0cb691aSEmil Constantinescu     binterpt[2][0]=1.75;
491c0cb691aSEmil Constantinescu     binterpt[3][0]=23.25;
492c0cb691aSEmil Constantinescu     binterpt[0][1]=-9.75;
493c0cb691aSEmil Constantinescu     binterpt[1][1]=58.75;
494c0cb691aSEmil Constantinescu     binterpt[2][1]=-3.25;
495c0cb691aSEmil Constantinescu     binterpt[3][1]=-45.75;
496c0cb691aSEmil Constantinescu     binterpt[0][2]=3.6666666666666666666666666666667;
497c0cb691aSEmil Constantinescu     binterpt[1][2]=-28.333333333333333333333333333333;
498c0cb691aSEmil Constantinescu     binterpt[2][2]=1.6666666666666666666666666666667;
499c0cb691aSEmil Constantinescu     binterpt[3][2]=23.;
500bbd56ea5SKarl Rupp 
501c0cb691aSEmil Constantinescu     ierr = TSRosWRegister(TSROSWLASSP3P4S2C,3,4,&A[0][0],&Gamma[0][0],b,b2,3,&binterpt[0][0]);CHKERRQ(ierr);
502b1c69cc3SEmil Constantinescu   }
503b1c69cc3SEmil Constantinescu 
504b1c69cc3SEmil Constantinescu   {
505b1c69cc3SEmil Constantinescu     const PetscReal
506b1c69cc3SEmil Constantinescu       A[4][4] = {{0,0,0,0},
507b1c69cc3SEmil Constantinescu                  {1./2.,0,0,0},
508b1c69cc3SEmil Constantinescu                  {1./2.,1./2.,0,0},
509b1c69cc3SEmil Constantinescu                  {1./6.,1./6.,1./6.,0}},
510b1c69cc3SEmil Constantinescu       Gamma[4][4] = {{1./2.,0,0,0},
511b1c69cc3SEmil Constantinescu                      {0.0,3./4.,0,0},
512b1c69cc3SEmil Constantinescu                      {-2./3.,-23./9.,2./9.,0},
513b1c69cc3SEmil Constantinescu                      {1./18.,65./108.,-2./27,0}},
514b1c69cc3SEmil Constantinescu       b[4]  = {1./6.,1./6.,1./6.,1./2.},
515b1c69cc3SEmil Constantinescu       b2[4] = {3./16.,10./16.,3./16.,0};
516c0cb691aSEmil Constantinescu     PetscReal binterpt[4][3];
517da80777bSKarl Rupp 
518c0cb691aSEmil Constantinescu     binterpt[0][0]=1.6911764705882352941176470588235;
519c0cb691aSEmil Constantinescu     binterpt[1][0]=3.6813725490196078431372549019608;
520c0cb691aSEmil Constantinescu     binterpt[2][0]=0.23039215686274509803921568627451;
521c0cb691aSEmil Constantinescu     binterpt[3][0]=-4.6029411764705882352941176470588;
522c0cb691aSEmil Constantinescu     binterpt[0][1]=-0.95588235294117647058823529411765;
523c0cb691aSEmil Constantinescu     binterpt[1][1]=-6.2401960784313725490196078431373;
524c0cb691aSEmil Constantinescu     binterpt[2][1]=-0.31862745098039215686274509803922;
525c0cb691aSEmil Constantinescu     binterpt[3][1]=7.5147058823529411764705882352941;
526c0cb691aSEmil Constantinescu     binterpt[0][2]=-0.56862745098039215686274509803922;
527c0cb691aSEmil Constantinescu     binterpt[1][2]=2.7254901960784313725490196078431;
528c0cb691aSEmil Constantinescu     binterpt[2][2]=0.25490196078431372549019607843137;
529c0cb691aSEmil Constantinescu     binterpt[3][2]=-2.4117647058823529411764705882353;
530bbd56ea5SKarl Rupp 
531c0cb691aSEmil Constantinescu     ierr = TSRosWRegister(TSROSWLLSSP3P4S2C,3,4,&A[0][0],&Gamma[0][0],b,b2,3,&binterpt[0][0]);CHKERRQ(ierr);
532b1c69cc3SEmil Constantinescu   }
533753f8adbSEmil Constantinescu 
534753f8adbSEmil Constantinescu   {
535753f8adbSEmil Constantinescu     PetscReal A[4][4],Gamma[4][4],b[4],b2[4];
5363ca35412SEmil Constantinescu     PetscReal binterpt[4][3];
537753f8adbSEmil Constantinescu 
538753f8adbSEmil Constantinescu     Gamma[0][0]=0.4358665215084589994160194475295062513822671686978816;
53905e8e825SJed Brown     Gamma[0][1]=0; Gamma[0][2]=0; Gamma[0][3]=0;
540753f8adbSEmil Constantinescu     Gamma[1][0]=-1.997527830934941248426324674704153457289527280554476;
541753f8adbSEmil Constantinescu     Gamma[1][1]=0.4358665215084589994160194475295062513822671686978816;
54205e8e825SJed Brown     Gamma[1][2]=0; Gamma[1][3]=0;
543753f8adbSEmil Constantinescu     Gamma[2][0]=-1.007948511795029620852002345345404191008352770119903;
544753f8adbSEmil Constantinescu     Gamma[2][1]=-0.004648958462629345562774289390054679806993396798458131;
545753f8adbSEmil Constantinescu     Gamma[2][2]=0.4358665215084589994160194475295062513822671686978816;
54605e8e825SJed Brown     Gamma[2][3]=0;
547753f8adbSEmil Constantinescu     Gamma[3][0]=-0.6685429734233467180451604600279552604364311322650783;
548753f8adbSEmil Constantinescu     Gamma[3][1]=0.6056625986449338476089525334450053439525178740492984;
549753f8adbSEmil Constantinescu     Gamma[3][2]=-0.9717899277217721234705114616271378792182450260943198;
550753f8adbSEmil Constantinescu     Gamma[3][3]=0;
551753f8adbSEmil Constantinescu 
55205e8e825SJed Brown     A[0][0]=0; A[0][1]=0; A[0][2]=0; A[0][3]=0;
553753f8adbSEmil Constantinescu     A[1][0]=0.8717330430169179988320388950590125027645343373957631;
55405e8e825SJed Brown     A[1][1]=0; A[1][2]=0; A[1][3]=0;
555753f8adbSEmil Constantinescu     A[2][0]=0.5275890119763004115618079766722914408876108660811028;
556753f8adbSEmil Constantinescu     A[2][1]=0.07241098802369958843819203208518599088698057726988732;
55705e8e825SJed Brown     A[2][2]=0; A[2][3]=0;
558753f8adbSEmil Constantinescu     A[3][0]=0.3990960076760701320627260685975778145384666450351314;
559753f8adbSEmil Constantinescu     A[3][1]=-0.4375576546135194437228463747348862825846903771419953;
560753f8adbSEmil Constantinescu     A[3][2]=1.038461646937449311660120300601880176655352737312713;
56105e8e825SJed Brown     A[3][3]=0;
562753f8adbSEmil Constantinescu 
563753f8adbSEmil Constantinescu     b[0]=0.1876410243467238251612921333138006734899663569186926;
564753f8adbSEmil Constantinescu     b[1]=-0.5952974735769549480478230473706443582188442040780541;
565753f8adbSEmil Constantinescu     b[2]=0.9717899277217721234705114616271378792182450260943198;
566753f8adbSEmil Constantinescu     b[3]=0.4358665215084589994160194475295062513822671686978816;
567753f8adbSEmil Constantinescu 
568753f8adbSEmil Constantinescu     b2[0]=0.2147402862233891404862383521089097657790734483804460;
569753f8adbSEmil Constantinescu     b2[1]=-0.4851622638849390928209050538171743017757490232519684;
570753f8adbSEmil Constantinescu     b2[2]=0.8687250025203875511662123688667549217531982787600080;
571753f8adbSEmil Constantinescu     b2[3]=0.4016969751411624011684543450940068201770721128357014;
572753f8adbSEmil Constantinescu 
5733ca35412SEmil Constantinescu     binterpt[0][0]=2.2565812720167954547104627844105;
5743ca35412SEmil Constantinescu     binterpt[1][0]=1.349166413351089573796243820819;
5753ca35412SEmil Constantinescu     binterpt[2][0]=-2.4695174540533503758652847586647;
5763ca35412SEmil Constantinescu     binterpt[3][0]=-0.13623023131453465264142184656474;
5773ca35412SEmil Constantinescu     binterpt[0][1]=-3.0826699111559187902922463354557;
5783ca35412SEmil Constantinescu     binterpt[1][1]=-2.4689115685996042534544925650515;
5793ca35412SEmil Constantinescu     binterpt[2][1]=5.7428279814696677152129332773553;
5803ca35412SEmil Constantinescu     binterpt[3][1]=-0.19124650171414467146619437684812;
5813ca35412SEmil Constantinescu     binterpt[0][2]=1.0137296634858471607430756831148;
5823ca35412SEmil Constantinescu     binterpt[1][2]=0.52444768167155973161042570784064;
5833ca35412SEmil Constantinescu     binterpt[2][2]=-2.3015205996945452158771370439586;
5843ca35412SEmil Constantinescu     binterpt[3][2]=0.76334325453713832352363565300308;
585f4aed992SEmil Constantinescu 
586f73f8d2cSSatish Balay     ierr = TSRosWRegister(TSROSWARK3,3,4,&A[0][0],&Gamma[0][0],b,b2,3,&binterpt[0][0]);CHKERRQ(ierr);
587753f8adbSEmil Constantinescu   }
58842faf41dSJed Brown   ierr = TSRosWRegisterRos4(TSROSWGRK4T,0.231,PETSC_DEFAULT,PETSC_DEFAULT,0,-0.1282612945269037e+01);CHKERRQ(ierr);
58942faf41dSJed Brown   ierr = TSRosWRegisterRos4(TSROSWSHAMP4,0.5,PETSC_DEFAULT,PETSC_DEFAULT,0,125./108.);CHKERRQ(ierr);
59042faf41dSJed Brown   ierr = TSRosWRegisterRos4(TSROSWVELDD4,0.22570811482256823492,PETSC_DEFAULT,PETSC_DEFAULT,0,-1.355958941201148);CHKERRQ(ierr);
59142faf41dSJed Brown   ierr = TSRosWRegisterRos4(TSROSW4L,0.57282,PETSC_DEFAULT,PETSC_DEFAULT,0,-1.093502252409163);CHKERRQ(ierr);
592e27a552bSJed Brown   PetscFunctionReturn(0);
593e27a552bSJed Brown }
594e27a552bSJed Brown 
595d5e6173cSPeter Brune 
596d5e6173cSPeter Brune 
597e27a552bSJed Brown /*@C
598e27a552bSJed Brown    TSRosWRegisterDestroy - Frees the list of schemes that were registered by TSRosWRegister().
599e27a552bSJed Brown 
600e27a552bSJed Brown    Not Collective
601e27a552bSJed Brown 
602e27a552bSJed Brown    Level: advanced
603e27a552bSJed Brown 
604607a6623SBarry Smith .seealso: TSRosWRegister(), TSRosWRegisterAll()
605e27a552bSJed Brown @*/
606e27a552bSJed Brown PetscErrorCode TSRosWRegisterDestroy(void)
607e27a552bSJed Brown {
608e27a552bSJed Brown   PetscErrorCode  ierr;
60961692a83SJed Brown   RosWTableauLink link;
610e27a552bSJed Brown 
611e27a552bSJed Brown   PetscFunctionBegin;
61261692a83SJed Brown   while ((link = RosWTableauList)) {
61361692a83SJed Brown     RosWTableau t = &link->tab;
61461692a83SJed Brown     RosWTableauList = link->next;
61561692a83SJed Brown     ierr = PetscFree5(t->A,t->Gamma,t->b,t->ASum,t->GammaSum);CHKERRQ(ierr);
61643b21953SEmil Constantinescu     ierr = PetscFree5(t->At,t->bt,t->GammaInv,t->GammaZeroDiag,t->GammaExplicitCorr);CHKERRQ(ierr);
617fe7e6d57SJed Brown     ierr = PetscFree2(t->bembed,t->bembedt);CHKERRQ(ierr);
618f4aed992SEmil Constantinescu     ierr = PetscFree(t->binterpt);CHKERRQ(ierr);
619e27a552bSJed Brown     ierr = PetscFree(t->name);CHKERRQ(ierr);
620e27a552bSJed Brown     ierr = PetscFree(link);CHKERRQ(ierr);
621e27a552bSJed Brown   }
622e27a552bSJed Brown   TSRosWRegisterAllCalled = PETSC_FALSE;
623e27a552bSJed Brown   PetscFunctionReturn(0);
624e27a552bSJed Brown }
625e27a552bSJed Brown 
626e27a552bSJed Brown /*@C
627e27a552bSJed Brown   TSRosWInitializePackage - This function initializes everything in the TSRosW package. It is called
6288a690491SBarry Smith   from TSInitializePackage().
629e27a552bSJed Brown 
630e27a552bSJed Brown   Level: developer
631e27a552bSJed Brown 
632e27a552bSJed Brown .seealso: PetscInitialize()
633e27a552bSJed Brown @*/
634607a6623SBarry Smith PetscErrorCode TSRosWInitializePackage(void)
635e27a552bSJed Brown {
636e27a552bSJed Brown   PetscErrorCode ierr;
637e27a552bSJed Brown 
638e27a552bSJed Brown   PetscFunctionBegin;
639e27a552bSJed Brown   if (TSRosWPackageInitialized) PetscFunctionReturn(0);
640e27a552bSJed Brown   TSRosWPackageInitialized = PETSC_TRUE;
641e27a552bSJed Brown   ierr = TSRosWRegisterAll();CHKERRQ(ierr);
642e27a552bSJed Brown   ierr = PetscRegisterFinalize(TSRosWFinalizePackage);CHKERRQ(ierr);
643e27a552bSJed Brown   PetscFunctionReturn(0);
644e27a552bSJed Brown }
645e27a552bSJed Brown 
646e27a552bSJed Brown /*@C
647e27a552bSJed Brown   TSRosWFinalizePackage - This function destroys everything in the TSRosW package. It is
648e27a552bSJed Brown   called from PetscFinalize().
649e27a552bSJed Brown 
650e27a552bSJed Brown   Level: developer
651e27a552bSJed Brown 
652e27a552bSJed Brown .seealso: PetscFinalize()
653e27a552bSJed Brown @*/
654e27a552bSJed Brown PetscErrorCode TSRosWFinalizePackage(void)
655e27a552bSJed Brown {
656e27a552bSJed Brown   PetscErrorCode ierr;
657e27a552bSJed Brown 
658e27a552bSJed Brown   PetscFunctionBegin;
659e27a552bSJed Brown   TSRosWPackageInitialized = PETSC_FALSE;
660e27a552bSJed Brown   ierr = TSRosWRegisterDestroy();CHKERRQ(ierr);
661e27a552bSJed Brown   PetscFunctionReturn(0);
662e27a552bSJed Brown }
663e27a552bSJed Brown 
664e27a552bSJed Brown /*@C
66561692a83SJed Brown    TSRosWRegister - register a Rosenbrock W scheme by providing the entries in the Butcher tableau and optionally embedded approximations and interpolation
666e27a552bSJed Brown 
667e27a552bSJed Brown    Not Collective, but the same schemes should be registered on all processes on which they will be used
668e27a552bSJed Brown 
669e27a552bSJed Brown    Input Parameters:
670e27a552bSJed Brown +  name - identifier for method
671e27a552bSJed Brown .  order - approximation order of method
672e27a552bSJed Brown .  s - number of stages, this is the dimension of the matrices below
67361692a83SJed Brown .  A - Table of propagated stage coefficients (dimension s*s, row-major), strictly lower triangular
67461692a83SJed Brown .  Gamma - Table of coefficients in implicit stage equations (dimension s*s, row-major), lower triangular with nonzero diagonal
675fe7e6d57SJed Brown .  b - Step completion table (dimension s)
6760298fd71SBarry Smith .  bembed - Step completion table for a scheme of order one less (dimension s, NULL if no embedded scheme is available)
677f4aed992SEmil Constantinescu .  pinterp - Order of the interpolation scheme, equal to the number of columns of binterpt
67842faf41dSJed Brown -  binterpt - Coefficients of the interpolation formula (dimension s*pinterp)
679e27a552bSJed Brown 
680e27a552bSJed Brown    Notes:
68161692a83SJed Brown    Several Rosenbrock W methods are provided, this function is only needed to create new methods.
682e27a552bSJed Brown 
683e27a552bSJed Brown    Level: advanced
684e27a552bSJed Brown 
685e27a552bSJed Brown .seealso: TSRosW
686e27a552bSJed Brown @*/
687f9c1d6abSBarry Smith PetscErrorCode TSRosWRegister(TSRosWType name,PetscInt order,PetscInt s,const PetscReal A[],const PetscReal Gamma[],const PetscReal b[],const PetscReal bembed[],
688f4aed992SEmil Constantinescu                               PetscInt pinterp,const PetscReal binterpt[])
689e27a552bSJed Brown {
690e27a552bSJed Brown   PetscErrorCode  ierr;
69161692a83SJed Brown   RosWTableauLink link;
69261692a83SJed Brown   RosWTableau     t;
69361692a83SJed Brown   PetscInt        i,j,k;
69461692a83SJed Brown   PetscScalar     *GammaInv;
695e27a552bSJed Brown 
696e27a552bSJed Brown   PetscFunctionBegin;
697fe7e6d57SJed Brown   PetscValidCharPointer(name,1);
698fe7e6d57SJed Brown   PetscValidPointer(A,4);
699fe7e6d57SJed Brown   PetscValidPointer(Gamma,5);
700fe7e6d57SJed Brown   PetscValidPointer(b,6);
701fe7e6d57SJed Brown   if (bembed) PetscValidPointer(bembed,7);
702fe7e6d57SJed Brown 
7031d36bdfdSBarry Smith   ierr     = TSRosWInitializePackage();CHKERRQ(ierr);
704071fcb05SBarry Smith   ierr     = PetscNew(&link);CHKERRQ(ierr);
705e27a552bSJed Brown   t        = &link->tab;
706e27a552bSJed Brown   ierr     = PetscStrallocpy(name,&t->name);CHKERRQ(ierr);
707e27a552bSJed Brown   t->order = order;
708e27a552bSJed Brown   t->s     = s;
709dcca6d9dSJed Brown   ierr     = PetscMalloc5(s*s,&t->A,s*s,&t->Gamma,s,&t->b,s,&t->ASum,s,&t->GammaSum);CHKERRQ(ierr);
710dcca6d9dSJed Brown   ierr     = PetscMalloc5(s*s,&t->At,s,&t->bt,s*s,&t->GammaInv,s,&t->GammaZeroDiag,s*s,&t->GammaExplicitCorr);CHKERRQ(ierr);
711580bdb30SBarry Smith   ierr     = PetscArraycpy(t->A,A,s*s);CHKERRQ(ierr);
712580bdb30SBarry Smith   ierr     = PetscArraycpy(t->Gamma,Gamma,s*s);CHKERRQ(ierr);
713580bdb30SBarry Smith   ierr     = PetscArraycpy(t->GammaExplicitCorr,Gamma,s*s);CHKERRQ(ierr);
714580bdb30SBarry Smith   ierr     = PetscArraycpy(t->b,b,s);CHKERRQ(ierr);
715fe7e6d57SJed Brown   if (bembed) {
716dcca6d9dSJed Brown     ierr = PetscMalloc2(s,&t->bembed,s,&t->bembedt);CHKERRQ(ierr);
717580bdb30SBarry Smith     ierr = PetscArraycpy(t->bembed,bembed,s);CHKERRQ(ierr);
718fe7e6d57SJed Brown   }
71961692a83SJed Brown   for (i=0; i<s; i++) {
72061692a83SJed Brown     t->ASum[i]     = 0;
72161692a83SJed Brown     t->GammaSum[i] = 0;
72261692a83SJed Brown     for (j=0; j<s; j++) {
72361692a83SJed Brown       t->ASum[i]     += A[i*s+j];
724fe7e6d57SJed Brown       t->GammaSum[i] += Gamma[i*s+j];
72561692a83SJed Brown     }
72661692a83SJed Brown   }
727785e854fSJed Brown   ierr = PetscMalloc1(s*s,&GammaInv);CHKERRQ(ierr); /* Need to use Scalar for inverse, then convert back to Real */
72861692a83SJed Brown   for (i=0; i<s*s; i++) GammaInv[i] = Gamma[i];
729fd96d5b0SEmil Constantinescu   for (i=0; i<s; i++) {
730fd96d5b0SEmil Constantinescu     if (Gamma[i*s+i] == 0.0) {
731fd96d5b0SEmil Constantinescu       GammaInv[i*s+i] = 1.0;
732c17803e7SJed Brown       t->GammaZeroDiag[i] = PETSC_TRUE;
733fd96d5b0SEmil Constantinescu     } else {
734c17803e7SJed Brown       t->GammaZeroDiag[i] = PETSC_FALSE;
735fd96d5b0SEmil Constantinescu     }
736fd96d5b0SEmil Constantinescu   }
737fd96d5b0SEmil Constantinescu 
73861692a83SJed Brown   switch (s) {
73961692a83SJed Brown   case 1: GammaInv[0] = 1./GammaInv[0]; break;
7402e92ee13SHong Zhang   case 2: ierr = PetscKernel_A_gets_inverse_A_2(GammaInv,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
7416baedc03SHong Zhang   case 3: ierr = PetscKernel_A_gets_inverse_A_3(GammaInv,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
7422e92ee13SHong Zhang   case 4: ierr = PetscKernel_A_gets_inverse_A_4(GammaInv,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
74361692a83SJed Brown   case 5: {
74461692a83SJed Brown     PetscInt  ipvt5[5];
74561692a83SJed Brown     MatScalar work5[5*5];
7462e92ee13SHong Zhang     ierr = PetscKernel_A_gets_inverse_A_5(GammaInv,ipvt5,work5,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
74761692a83SJed Brown   }
7482e92ee13SHong Zhang   case 6: ierr = PetscKernel_A_gets_inverse_A_6(GammaInv,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
7492e92ee13SHong Zhang   case 7: ierr = PetscKernel_A_gets_inverse_A_7(GammaInv,0,PETSC_FALSE,NULL);CHKERRQ(ierr); break;
75061692a83SJed Brown   default: SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Not implemented for %D stages",s);
75161692a83SJed Brown   }
75261692a83SJed Brown   for (i=0; i<s*s; i++) t->GammaInv[i] = PetscRealPart(GammaInv[i]);
75361692a83SJed Brown   ierr = PetscFree(GammaInv);CHKERRQ(ierr);
75443b21953SEmil Constantinescu 
75543b21953SEmil Constantinescu   for (i=0; i<s; i++) {
75643b21953SEmil Constantinescu     for (k=0; k<i+1; k++) {
75743b21953SEmil Constantinescu       t->GammaExplicitCorr[i*s+k]=(t->GammaExplicitCorr[i*s+k])*(t->GammaInv[k*s+k]);
75843b21953SEmil Constantinescu       for (j=k+1; j<i+1; j++) {
75943b21953SEmil Constantinescu         t->GammaExplicitCorr[i*s+k]+=(t->GammaExplicitCorr[i*s+j])*(t->GammaInv[j*s+k]);
76043b21953SEmil Constantinescu       }
76143b21953SEmil Constantinescu     }
76243b21953SEmil Constantinescu   }
76343b21953SEmil Constantinescu 
76461692a83SJed Brown   for (i=0; i<s; i++) {
76561692a83SJed Brown     for (j=0; j<s; j++) {
76661692a83SJed Brown       t->At[i*s+j] = 0;
76761692a83SJed Brown       for (k=0; k<s; k++) {
76861692a83SJed Brown         t->At[i*s+j] += t->A[i*s+k] * t->GammaInv[k*s+j];
76961692a83SJed Brown       }
77061692a83SJed Brown     }
77161692a83SJed Brown     t->bt[i] = 0;
77261692a83SJed Brown     for (j=0; j<s; j++) {
77361692a83SJed Brown       t->bt[i] += t->b[j] * t->GammaInv[j*s+i];
77461692a83SJed Brown     }
775fe7e6d57SJed Brown     if (bembed) {
776fe7e6d57SJed Brown       t->bembedt[i] = 0;
777fe7e6d57SJed Brown       for (j=0; j<s; j++) {
778fe7e6d57SJed Brown         t->bembedt[i] += t->bembed[j] * t->GammaInv[j*s+i];
779fe7e6d57SJed Brown       }
780fe7e6d57SJed Brown     }
78161692a83SJed Brown   }
7828d59e960SJed Brown   t->ccfl = 1.0;                /* Fix this */
7838d59e960SJed Brown 
784f4aed992SEmil Constantinescu   t->pinterp = pinterp;
785785e854fSJed Brown   ierr = PetscMalloc1(s*pinterp,&t->binterpt);CHKERRQ(ierr);
786580bdb30SBarry Smith   ierr = PetscArraycpy(t->binterpt,binterpt,s*pinterp);CHKERRQ(ierr);
78761692a83SJed Brown   link->next = RosWTableauList;
78861692a83SJed Brown   RosWTableauList = link;
789e27a552bSJed Brown   PetscFunctionReturn(0);
790e27a552bSJed Brown }
791e27a552bSJed Brown 
79242faf41dSJed Brown /*@C
793fd292e60Sprj-    TSRosWRegisterRos4 - register a fourth order Rosenbrock scheme by providing parameter choices
79442faf41dSJed Brown 
79542faf41dSJed Brown    Not Collective, but the same schemes should be registered on all processes on which they will be used
79642faf41dSJed Brown 
79742faf41dSJed Brown    Input Parameters:
79842faf41dSJed Brown +  name - identifier for method
79942faf41dSJed Brown .  gamma - leading coefficient (diagonal entry)
80042faf41dSJed Brown .  a2 - design parameter, see Table 7.2 of Hairer&Wanner
80142faf41dSJed Brown .  a3 - design parameter or PETSC_DEFAULT to satisfy one of the order five conditions (Eq 7.22)
80242faf41dSJed Brown .  b3 - design parameter, see Table 7.2 of Hairer&Wanner
80342faf41dSJed Brown .  beta43 - design parameter or PETSC_DEFAULT to use Equation 7.21 of Hairer&Wanner
804a2b725a8SWilliam Gropp -  e4 - design parameter for embedded method, see coefficient E4 in ros4.f code from Hairer
80542faf41dSJed Brown 
80642faf41dSJed Brown    Notes:
80742faf41dSJed Brown    This routine encodes the design of fourth order Rosenbrock methods as described in Hairer and Wanner volume 2.
80842faf41dSJed Brown    It is used here to implement several methods from the book and can be used to experiment with new methods.
80942faf41dSJed Brown    It was written this way instead of by copying coefficients in order to provide better than double precision satisfaction of the order conditions.
81042faf41dSJed Brown 
81142faf41dSJed Brown    Level: developer
81242faf41dSJed Brown 
81342faf41dSJed Brown .seealso: TSRosW, TSRosWRegister()
81442faf41dSJed Brown @*/
81519fd82e9SBarry Smith PetscErrorCode TSRosWRegisterRos4(TSRosWType name,PetscReal gamma,PetscReal a2,PetscReal a3,PetscReal b3,PetscReal e4)
81642faf41dSJed Brown {
81742faf41dSJed Brown   PetscErrorCode ierr;
81842faf41dSJed Brown   /* Declare numeric constants so they can be quad precision without being truncated at double */
81942faf41dSJed Brown   const PetscReal one = 1,two = 2,three = 3,four = 4,five = 5,six = 6,eight = 8,twelve = 12,twenty = 20,twentyfour = 24,
82042faf41dSJed Brown     p32 = one/six - gamma + gamma*gamma,
82142faf41dSJed Brown     p42 = one/eight - gamma/three,
82242faf41dSJed Brown     p43 = one/twelve - gamma/three,
82342faf41dSJed Brown     p44 = one/twentyfour - gamma/two + three/two*gamma*gamma - gamma*gamma*gamma,
82442faf41dSJed Brown     p56 = one/twenty - gamma/four;
82542faf41dSJed Brown   PetscReal   a4,a32,a42,a43,b1,b2,b4,beta2p,beta3p,beta4p,beta32,beta42,beta43,beta32beta2p,beta4jbetajp;
82642faf41dSJed Brown   PetscReal   A[4][4],Gamma[4][4],b[4],bm[4];
82742faf41dSJed Brown   PetscScalar M[3][3],rhs[3];
82842faf41dSJed Brown 
82942faf41dSJed Brown   PetscFunctionBegin;
83042faf41dSJed Brown   /* Step 1: choose Gamma (input) */
83142faf41dSJed Brown   /* Step 2: choose a2,a3,a4; b1,b2,b3,b4 to satisfy order conditions */
83242faf41dSJed Brown   if (a3 == PETSC_DEFAULT) a3 = (one/five - a2/four)/(one/four - a2/three); /* Eq 7.22 */
83342faf41dSJed Brown   a4 = a3;                                                  /* consequence of 7.20 */
83442faf41dSJed Brown 
83542faf41dSJed Brown   /* Solve order conditions 7.15a, 7.15c, 7.15e */
83642faf41dSJed Brown   M[0][0] = one; M[0][1] = one;      M[0][2] = one;      /* 7.15a */
83742faf41dSJed Brown   M[1][0] = 0.0; M[1][1] = a2*a2;    M[1][2] = a4*a4;    /* 7.15c */
83842faf41dSJed Brown   M[2][0] = 0.0; M[2][1] = a2*a2*a2; M[2][2] = a4*a4*a4; /* 7.15e */
83942faf41dSJed Brown   rhs[0]  = one - b3;
84042faf41dSJed Brown   rhs[1]  = one/three - a3*a3*b3;
84142faf41dSJed Brown   rhs[2]  = one/four - a3*a3*a3*b3;
8426baedc03SHong Zhang   ierr    = PetscKernel_A_gets_inverse_A_3(&M[0][0],0,PETSC_FALSE,NULL);CHKERRQ(ierr);
84342faf41dSJed Brown   b1      = PetscRealPart(M[0][0]*rhs[0] + M[0][1]*rhs[1] + M[0][2]*rhs[2]);
84442faf41dSJed Brown   b2      = PetscRealPart(M[1][0]*rhs[0] + M[1][1]*rhs[1] + M[1][2]*rhs[2]);
84542faf41dSJed Brown   b4      = PetscRealPart(M[2][0]*rhs[0] + M[2][1]*rhs[1] + M[2][2]*rhs[2]);
84642faf41dSJed Brown 
84742faf41dSJed Brown   /* Step 3 */
84842faf41dSJed Brown   beta43       = (p56 - a2*p43) / (b4*a3*a3*(a3 - a2)); /* 7.21 */
84942faf41dSJed Brown   beta32beta2p =  p44 / (b4*beta43);                    /* 7.15h */
85042faf41dSJed Brown   beta4jbetajp = (p32 - b3*beta32beta2p) / b4;
85142faf41dSJed Brown   M[0][0]      = b2;                                    M[0][1] = b3;                 M[0][2] = b4;
85242faf41dSJed Brown   M[1][0]      = a4*a4*beta32beta2p-a3*a3*beta4jbetajp; M[1][1] = a2*a2*beta4jbetajp; M[1][2] = -a2*a2*beta32beta2p;
85342faf41dSJed Brown   M[2][0]      = b4*beta43*a3*a3-p43;                   M[2][1] = -b4*beta43*a2*a2;   M[2][2] = 0;
85442faf41dSJed Brown   rhs[0]       = one/two - gamma; rhs[1] = 0; rhs[2] = -a2*a2*p32;
8556baedc03SHong Zhang   ierr         = PetscKernel_A_gets_inverse_A_3(&M[0][0],0,PETSC_FALSE,NULL);CHKERRQ(ierr);
85642faf41dSJed Brown   beta2p       = PetscRealPart(M[0][0]*rhs[0] + M[0][1]*rhs[1] + M[0][2]*rhs[2]);
85742faf41dSJed Brown   beta3p       = PetscRealPart(M[1][0]*rhs[0] + M[1][1]*rhs[1] + M[1][2]*rhs[2]);
85842faf41dSJed Brown   beta4p       = PetscRealPart(M[2][0]*rhs[0] + M[2][1]*rhs[1] + M[2][2]*rhs[2]);
85942faf41dSJed Brown 
86042faf41dSJed Brown   /* Step 4: back-substitute */
86142faf41dSJed Brown   beta32 = beta32beta2p / beta2p;
86242faf41dSJed Brown   beta42 = (beta4jbetajp - beta43*beta3p) / beta2p;
86342faf41dSJed Brown 
86442faf41dSJed Brown   /* Step 5: 7.15f and 7.20, then 7.16 */
86542faf41dSJed Brown   a43 = 0;
86642faf41dSJed Brown   a32 = p42 / (b3*a3*beta2p + b4*a4*beta2p);
86742faf41dSJed Brown   a42 = a32;
86842faf41dSJed Brown 
86942faf41dSJed Brown   A[0][0]     = 0;          A[0][1] = 0;   A[0][2] = 0;   A[0][3] = 0;
87042faf41dSJed Brown   A[1][0]     = a2;         A[1][1] = 0;   A[1][2] = 0;   A[1][3] = 0;
87142faf41dSJed Brown   A[2][0]     = a3-a32;     A[2][1] = a32; A[2][2] = 0;   A[2][3] = 0;
87242faf41dSJed Brown   A[3][0]     = a4-a43-a42; A[3][1] = a42; A[3][2] = a43; A[3][3] = 0;
87342faf41dSJed Brown   Gamma[0][0] = gamma;                        Gamma[0][1] = 0;              Gamma[0][2] = 0;              Gamma[0][3] = 0;
87442faf41dSJed Brown   Gamma[1][0] = beta2p-A[1][0];               Gamma[1][1] = gamma;          Gamma[1][2] = 0;              Gamma[1][3] = 0;
87542faf41dSJed Brown   Gamma[2][0] = beta3p-beta32-A[2][0];        Gamma[2][1] = beta32-A[2][1]; Gamma[2][2] = gamma;          Gamma[2][3] = 0;
87642faf41dSJed Brown   Gamma[3][0] = beta4p-beta42-beta43-A[3][0]; Gamma[3][1] = beta42-A[3][1]; Gamma[3][2] = beta43-A[3][2]; Gamma[3][3] = gamma;
87742faf41dSJed Brown   b[0] = b1; b[1] = b2; b[2] = b3; b[3] = b4;
87842faf41dSJed Brown 
87942faf41dSJed Brown   /* Construct embedded formula using given e4. We are solving Equation 7.18. */
88042faf41dSJed Brown   bm[3] = b[3] - e4*gamma;                                          /* using definition of E4 */
88142faf41dSJed Brown   bm[2] = (p32 - beta4jbetajp*bm[3]) / (beta32*beta2p);             /* fourth row of 7.18 */
88242faf41dSJed Brown   bm[1] = (one/two - gamma - beta3p*bm[2] - beta4p*bm[3]) / beta2p; /* second row */
88342faf41dSJed Brown   bm[0] = one - bm[1] - bm[2] - bm[3];                              /* first row */
88442faf41dSJed Brown 
88542faf41dSJed Brown   {
88642faf41dSJed Brown     const PetscReal misfit = a2*a2*bm[1] + a3*a3*bm[2] + a4*a4*bm[3] - one/three;
88742faf41dSJed Brown     if (PetscAbs(misfit) > PETSC_SMALL) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Assumptions violated, could not construct a third order embedded method");
88842faf41dSJed Brown   }
8890298fd71SBarry Smith   ierr = TSRosWRegister(name,4,4,&A[0][0],&Gamma[0][0],b,bm,0,NULL);CHKERRQ(ierr);
89042faf41dSJed Brown   PetscFunctionReturn(0);
89142faf41dSJed Brown }
89242faf41dSJed Brown 
8931c3436cfSJed Brown /*
8941c3436cfSJed Brown  The step completion formula is
8951c3436cfSJed Brown 
8961c3436cfSJed Brown  x1 = x0 + b^T Y
8971c3436cfSJed Brown 
8981c3436cfSJed Brown  where Y is the multi-vector of stages corrections. This function can be called before or after ts->vec_sol has been
8991c3436cfSJed Brown  updated. Suppose we have a completion formula b and an embedded formula be of different order. We can write
9001c3436cfSJed Brown 
9011c3436cfSJed Brown  x1e = x0 + be^T Y
9021c3436cfSJed Brown      = x1 - b^T Y + be^T Y
9031c3436cfSJed Brown      = x1 + (be - b)^T Y
9041c3436cfSJed Brown 
9051c3436cfSJed Brown  so we can evaluate the method of different order even after the step has been optimistically completed.
9061c3436cfSJed Brown */
907f9c1d6abSBarry Smith static PetscErrorCode TSEvaluateStep_RosW(TS ts,PetscInt order,Vec U,PetscBool *done)
9081c3436cfSJed Brown {
9091c3436cfSJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
9101c3436cfSJed Brown   RosWTableau    tab  = ros->tableau;
9111c3436cfSJed Brown   PetscScalar    *w   = ros->work;
9121c3436cfSJed Brown   PetscInt       i;
9131c3436cfSJed Brown   PetscErrorCode ierr;
9141c3436cfSJed Brown 
9151c3436cfSJed Brown   PetscFunctionBegin;
9161c3436cfSJed Brown   if (order == tab->order) {
917108c343cSJed Brown     if (ros->status == TS_STEP_INCOMPLETE) { /* Use standard completion formula */
918f9c1d6abSBarry Smith       ierr = VecCopy(ts->vec_sol,U);CHKERRQ(ierr);
919de19f811SJed Brown       for (i=0; i<tab->s; i++) w[i] = tab->bt[i];
920f9c1d6abSBarry Smith       ierr = VecMAXPY(U,tab->s,w,ros->Y);CHKERRQ(ierr);
921f9c1d6abSBarry Smith     } else {ierr = VecCopy(ts->vec_sol,U);CHKERRQ(ierr);}
9221c3436cfSJed Brown     if (done) *done = PETSC_TRUE;
9231c3436cfSJed Brown     PetscFunctionReturn(0);
9241c3436cfSJed Brown   } else if (order == tab->order-1) {
9251c3436cfSJed Brown     if (!tab->bembedt) goto unavailable;
926108c343cSJed Brown     if (ros->status == TS_STEP_INCOMPLETE) { /* Use embedded completion formula */
927f9c1d6abSBarry Smith       ierr = VecCopy(ts->vec_sol,U);CHKERRQ(ierr);
928de19f811SJed Brown       for (i=0; i<tab->s; i++) w[i] = tab->bembedt[i];
929f9c1d6abSBarry Smith       ierr = VecMAXPY(U,tab->s,w,ros->Y);CHKERRQ(ierr);
930108c343cSJed Brown     } else {                    /* Use rollback-and-recomplete formula (bembedt - bt) */
931108c343cSJed Brown       for (i=0; i<tab->s; i++) w[i] = tab->bembedt[i] - tab->bt[i];
932f9c1d6abSBarry Smith       ierr = VecCopy(ts->vec_sol,U);CHKERRQ(ierr);
933f9c1d6abSBarry Smith       ierr = VecMAXPY(U,tab->s,w,ros->Y);CHKERRQ(ierr);
9341c3436cfSJed Brown     }
9351c3436cfSJed Brown     if (done) *done = PETSC_TRUE;
9361c3436cfSJed Brown     PetscFunctionReturn(0);
9371c3436cfSJed Brown   }
9381c3436cfSJed Brown   unavailable:
9391c3436cfSJed Brown   if (done) *done = PETSC_FALSE;
940a7fac7c2SEmil Constantinescu   else SETERRQ3(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Rosenbrock-W '%s' of order %D cannot evaluate step at order %D. Consider using -ts_adapt_type none or a different method that has an embedded estimate.",tab->name,tab->order,order);
9411c3436cfSJed Brown   PetscFunctionReturn(0);
9421c3436cfSJed Brown }
9431c3436cfSJed Brown 
944560360afSLisandro Dalcin static PetscErrorCode TSRollBack_RosW(TS ts)
94524655328SShri {
94624655328SShri   TS_RosW        *ros = (TS_RosW*)ts->data;
94724655328SShri   PetscErrorCode ierr;
94824655328SShri 
94924655328SShri   PetscFunctionBegin;
950be5899b3SLisandro Dalcin   ierr = VecCopy(ros->vec_sol_prev,ts->vec_sol);CHKERRQ(ierr);
95124655328SShri   PetscFunctionReturn(0);
95224655328SShri }
95324655328SShri 
954e27a552bSJed Brown static PetscErrorCode TSStep_RosW(TS ts)
955e27a552bSJed Brown {
95661692a83SJed Brown   TS_RosW         *ros = (TS_RosW*)ts->data;
95761692a83SJed Brown   RosWTableau     tab  = ros->tableau;
958e27a552bSJed Brown   const PetscInt  s    = tab->s;
9591c3436cfSJed Brown   const PetscReal *At  = tab->At,*Gamma = tab->Gamma,*ASum = tab->ASum,*GammaInv = tab->GammaInv;
9600feba352SEmil Constantinescu   const PetscReal *GammaExplicitCorr = tab->GammaExplicitCorr;
961c17803e7SJed Brown   const PetscBool *GammaZeroDiag = tab->GammaZeroDiag;
96261692a83SJed Brown   PetscScalar     *w   = ros->work;
9637d4bf2deSEmil Constantinescu   Vec             *Y   = ros->Y,Ydot = ros->Ydot,Zdot = ros->Zdot,Zstage = ros->Zstage;
964e27a552bSJed Brown   SNES            snes;
9651c3436cfSJed Brown   TSAdapt         adapt;
966fecfb714SLisandro Dalcin   PetscInt        i,j,its,lits;
967be5899b3SLisandro Dalcin   PetscInt        rejections = 0;
968b39943a6SLisandro Dalcin   PetscBool       stageok,accept = PETSC_TRUE;
969b39943a6SLisandro Dalcin   PetscReal       next_time_step = ts->time_step;
970e27a552bSJed Brown   PetscErrorCode  ierr;
971f7f07198SBarry Smith   PetscInt        lag;
972e27a552bSJed Brown 
973e27a552bSJed Brown   PetscFunctionBegin;
974b39943a6SLisandro Dalcin   if (!ts->steprollback) {
975be5899b3SLisandro Dalcin     ierr = VecCopy(ts->vec_sol,ros->vec_sol_prev);CHKERRQ(ierr);
976b39943a6SLisandro Dalcin   }
977e27a552bSJed Brown 
978b39943a6SLisandro Dalcin   ros->status = TS_STEP_INCOMPLETE;
979b39943a6SLisandro Dalcin   while (!ts->reason && ros->status != TS_STEP_COMPLETE) {
9801c3436cfSJed Brown     const PetscReal h = ts->time_step;
981e27a552bSJed Brown     for (i=0; i<s; i++) {
9821c3436cfSJed Brown       ros->stage_time = ts->ptime + h*ASum[i];
983b8123daeSJed Brown       ierr = TSPreStage(ts,ros->stage_time);CHKERRQ(ierr);
984c17803e7SJed Brown       if (GammaZeroDiag[i]) {
985c17803e7SJed Brown         ros->stage_explicit = PETSC_TRUE;
986b296d7d5SJed Brown         ros->scoeff         = 1.;
987c17803e7SJed Brown       } else {
988c17803e7SJed Brown         ros->stage_explicit = PETSC_FALSE;
989b296d7d5SJed Brown         ros->scoeff         = 1./Gamma[i*s+i];
990fd96d5b0SEmil Constantinescu       }
99161692a83SJed Brown 
99261692a83SJed Brown       ierr = VecCopy(ts->vec_sol,Zstage);CHKERRQ(ierr);
993de19f811SJed Brown       for (j=0; j<i; j++) w[j] = At[i*s+j];
994de19f811SJed Brown       ierr = VecMAXPY(Zstage,i,w,Y);CHKERRQ(ierr);
99561692a83SJed Brown 
99661692a83SJed Brown       for (j=0; j<i; j++) w[j] = 1./h * GammaInv[i*s+j];
99761692a83SJed Brown       ierr = VecZeroEntries(Zdot);CHKERRQ(ierr);
99861692a83SJed Brown       ierr = VecMAXPY(Zdot,i,w,Y);CHKERRQ(ierr);
99961692a83SJed Brown 
1000e27a552bSJed Brown       /* Initial guess taken from last stage */
100161692a83SJed Brown       ierr = VecZeroEntries(Y[i]);CHKERRQ(ierr);
100261692a83SJed Brown 
10037d4bf2deSEmil Constantinescu       if (!ros->stage_explicit) {
1004b39943a6SLisandro Dalcin         ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
100561692a83SJed Brown         if (!ros->recompute_jacobian && !i) {
1006f7f07198SBarry Smith           ierr = SNESGetLagJacobian(snes,&lag);CHKERRQ(ierr);
1007f7f07198SBarry Smith           if (lag == 1) {  /* use did not set a nontrival lag, so lag over all stages */
1008f7f07198SBarry Smith             ierr = SNESSetLagJacobian(snes,-2);CHKERRQ(ierr); /* Recompute the Jacobian on this solve, but not again for the rest of the stages */
1009f7f07198SBarry Smith           }
101061692a83SJed Brown         }
10110298fd71SBarry Smith         ierr = SNESSolve(snes,NULL,Y[i]);CHKERRQ(ierr);
1012f7f07198SBarry Smith         if (!ros->recompute_jacobian && i == s-1 && lag == 1) {
1013f7f07198SBarry Smith           ierr = SNESSetLagJacobian(snes,lag);CHKERRQ(ierr); /* Set lag back to 1 so we know user did not set it */
1014f7f07198SBarry Smith         }
1015e27a552bSJed Brown         ierr = SNESGetIterationNumber(snes,&its);CHKERRQ(ierr);
1016e27a552bSJed Brown         ierr = SNESGetLinearSolveIterations(snes,&lits);CHKERRQ(ierr);
10175ef26d82SJed Brown         ts->snes_its += its; ts->ksp_its += lits;
10187d4bf2deSEmil Constantinescu       } else {
10191ce71dffSSatish Balay         Mat J,Jp;
10200feba352SEmil Constantinescu         ierr = VecZeroEntries(Ydot);CHKERRQ(ierr); /* Evaluate Y[i]=G(t,Ydot=0,Zstage) */
10210feba352SEmil Constantinescu         ierr = TSComputeIFunction(ts,ros->stage_time,Zstage,Ydot,Y[i],PETSC_FALSE);CHKERRQ(ierr);
102222d28d08SBarry Smith         ierr = VecScale(Y[i],-1.0);CHKERRQ(ierr);
10230feba352SEmil Constantinescu         ierr = VecAXPY(Y[i],-1.0,Zdot);CHKERRQ(ierr); /*Y[i] = F(Zstage)-Zdot[=GammaInv*Y]*/
10240feba352SEmil Constantinescu 
10250feba352SEmil Constantinescu         ierr = VecZeroEntries(Zstage);CHKERRQ(ierr); /* Zstage = GammaExplicitCorr[i,j] * Y[j] */
10260feba352SEmil Constantinescu         for (j=0; j<i; j++) w[j] = GammaExplicitCorr[i*s+j];
10270feba352SEmil Constantinescu         ierr = VecMAXPY(Zstage,i,w,Y);CHKERRQ(ierr);
1028fecfb714SLisandro Dalcin 
1029fecfb714SLisandro Dalcin         /* Y[i] = Y[i] + Jac*Zstage[=Jac*GammaExplicitCorr[i,j] * Y[j]] */
10300298fd71SBarry Smith         ierr = TSGetIJacobian(ts,&J,&Jp,NULL,NULL);CHKERRQ(ierr);
1031d1e9a80fSBarry Smith         ierr = TSComputeIJacobian(ts,ros->stage_time,ts->vec_sol,Ydot,0,J,Jp,PETSC_FALSE);CHKERRQ(ierr);
103222d28d08SBarry Smith         ierr = MatMult(J,Zstage,Zdot);CHKERRQ(ierr);
10330feba352SEmil Constantinescu         ierr = VecAXPY(Y[i],-1.0,Zdot);CHKERRQ(ierr);
10345ef26d82SJed Brown         ts->ksp_its += 1;
1035fecfb714SLisandro Dalcin 
1036fecfb714SLisandro Dalcin         ierr = VecScale(Y[i],h);CHKERRQ(ierr);
10377d4bf2deSEmil Constantinescu       }
10389be3e283SDebojyoti Ghosh       ierr = TSPostStage(ts,ros->stage_time,i,Y);CHKERRQ(ierr);
1039fecfb714SLisandro Dalcin       ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
1040fecfb714SLisandro Dalcin       ierr = TSAdaptCheckStage(adapt,ts,ros->stage_time,Y[i],&stageok);CHKERRQ(ierr);
1041fecfb714SLisandro Dalcin       if (!stageok) goto reject_step;
1042e27a552bSJed Brown     }
1043e27a552bSJed Brown 
1044b39943a6SLisandro Dalcin     ros->status = TS_STEP_INCOMPLETE;
1045b39943a6SLisandro Dalcin     ierr = TSEvaluateStep_RosW(ts,tab->order,ts->vec_sol,NULL);CHKERRQ(ierr);
1046b39943a6SLisandro Dalcin     ros->status = TS_STEP_PENDING;
1047552698daSJed Brown     ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
10481c3436cfSJed Brown     ierr = TSAdaptCandidatesClear(adapt);CHKERRQ(ierr);
10491917a363SLisandro Dalcin     ierr = TSAdaptCandidateAdd(adapt,tab->name,tab->order,1,tab->ccfl,(PetscReal)tab->s,PETSC_TRUE);CHKERRQ(ierr);
1050fecfb714SLisandro Dalcin     ierr = TSAdaptChoose(adapt,ts,ts->time_step,NULL,&next_time_step,&accept);CHKERRQ(ierr);
1051b39943a6SLisandro Dalcin     ros->status = accept ? TS_STEP_COMPLETE : TS_STEP_INCOMPLETE;
1052b39943a6SLisandro Dalcin     if (!accept) { /* Roll back the current step */
1053b39943a6SLisandro Dalcin       ierr = TSRollBack_RosW(ts);CHKERRQ(ierr);
1054be5899b3SLisandro Dalcin       ts->time_step = next_time_step;
1055be5899b3SLisandro Dalcin       goto reject_step;
1056b39943a6SLisandro Dalcin     }
1057b39943a6SLisandro Dalcin 
1058e27a552bSJed Brown     ts->ptime += ts->time_step;
1059cdbf8f93SLisandro Dalcin     ts->time_step = next_time_step;
10601c3436cfSJed Brown     break;
1061b39943a6SLisandro Dalcin 
1062b39943a6SLisandro Dalcin   reject_step:
1063fecfb714SLisandro Dalcin     ts->reject++; accept = PETSC_FALSE;
1064be5899b3SLisandro Dalcin     if (!ts->reason && ++rejections > ts->max_reject && ts->max_reject >= 0) {
1065b39943a6SLisandro Dalcin       ts->reason = TS_DIVERGED_STEP_REJECTED;
1066be5899b3SLisandro Dalcin       ierr = PetscInfo2(ts,"Step=%D, step rejections %D greater than current TS allowed, stopping solve\n",ts->steps,rejections);CHKERRQ(ierr);
10671c3436cfSJed Brown     }
10681c3436cfSJed Brown   }
1069e27a552bSJed Brown   PetscFunctionReturn(0);
1070e27a552bSJed Brown }
1071e27a552bSJed Brown 
1072f9c1d6abSBarry Smith static PetscErrorCode TSInterpolate_RosW(TS ts,PetscReal itime,Vec U)
1073e27a552bSJed Brown {
107461692a83SJed Brown   TS_RosW         *ros = (TS_RosW*)ts->data;
1075f4aed992SEmil Constantinescu   PetscInt        s    = ros->tableau->s,pinterp = ros->tableau->pinterp,i,j;
1076f4aed992SEmil Constantinescu   PetscReal       h;
1077f4aed992SEmil Constantinescu   PetscReal       tt,t;
1078f4aed992SEmil Constantinescu   PetscScalar     *bt;
1079f4aed992SEmil Constantinescu   const PetscReal *Bt = ros->tableau->binterpt;
1080f4aed992SEmil Constantinescu   PetscErrorCode  ierr;
1081f4aed992SEmil Constantinescu   const PetscReal *GammaInv = ros->tableau->GammaInv;
1082f4aed992SEmil Constantinescu   PetscScalar     *w        = ros->work;
1083f4aed992SEmil Constantinescu   Vec             *Y        = ros->Y;
1084e27a552bSJed Brown 
1085e27a552bSJed Brown   PetscFunctionBegin;
1086ce94432eSBarry Smith   if (!Bt) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSRosW %s does not have an interpolation formula",ros->tableau->name);
1087f4aed992SEmil Constantinescu 
1088f4aed992SEmil Constantinescu   switch (ros->status) {
1089f4aed992SEmil Constantinescu   case TS_STEP_INCOMPLETE:
1090f4aed992SEmil Constantinescu   case TS_STEP_PENDING:
1091f4aed992SEmil Constantinescu     h = ts->time_step;
1092f4aed992SEmil Constantinescu     t = (itime - ts->ptime)/h;
1093f4aed992SEmil Constantinescu     break;
1094f4aed992SEmil Constantinescu   case TS_STEP_COMPLETE:
1095be5899b3SLisandro Dalcin     h = ts->ptime - ts->ptime_prev;
1096f4aed992SEmil Constantinescu     t = (itime - ts->ptime)/h + 1; /* In the interval [0,1] */
1097f4aed992SEmil Constantinescu     break;
1098ce94432eSBarry Smith   default: SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_PLIB,"Invalid TSStepStatus");
1099f4aed992SEmil Constantinescu   }
1100785e854fSJed Brown   ierr = PetscMalloc1(s,&bt);CHKERRQ(ierr);
1101f4aed992SEmil Constantinescu   for (i=0; i<s; i++) bt[i] = 0;
1102f4aed992SEmil Constantinescu   for (j=0,tt=t; j<pinterp; j++,tt*=t) {
1103f4aed992SEmil Constantinescu     for (i=0; i<s; i++) {
11043ca35412SEmil Constantinescu       bt[i] += Bt[i*pinterp+j] * tt;
1105f4aed992SEmil Constantinescu     }
1106f4aed992SEmil Constantinescu   }
1107f4aed992SEmil Constantinescu 
1108f4aed992SEmil Constantinescu   /* y(t+tt*h) = y(t) + Sum bt(tt) * GammaInv * Ydot */
1109f9c1d6abSBarry Smith   /* U <- 0*/
1110f9c1d6abSBarry Smith   ierr = VecZeroEntries(U);CHKERRQ(ierr);
1111f9c1d6abSBarry Smith   /* U <- Sum bt_i * GammaInv(i,1:i) * Y(1:i) */
11123ca35412SEmil Constantinescu   for (j=0; j<s; j++) w[j] = 0;
11133ca35412SEmil Constantinescu   for (j=0; j<s; j++) {
11143ca35412SEmil Constantinescu     for (i=j; i<s; i++) {
11153ca35412SEmil Constantinescu       w[j] +=  bt[i]*GammaInv[i*s+j];
1116f4aed992SEmil Constantinescu     }
11173ca35412SEmil Constantinescu   }
1118f9c1d6abSBarry Smith   ierr = VecMAXPY(U,i,w,Y);CHKERRQ(ierr);
1119be5899b3SLisandro Dalcin   /* U <- y(t) + U */
1120be5899b3SLisandro Dalcin   ierr = VecAXPY(U,1,ros->vec_sol_prev);CHKERRQ(ierr);
1121f4aed992SEmil Constantinescu 
1122f4aed992SEmil Constantinescu   ierr = PetscFree(bt);CHKERRQ(ierr);
1123e27a552bSJed Brown   PetscFunctionReturn(0);
1124e27a552bSJed Brown }
1125e27a552bSJed Brown 
1126e27a552bSJed Brown /*------------------------------------------------------------*/
1127b39943a6SLisandro Dalcin 
1128b39943a6SLisandro Dalcin static PetscErrorCode TSRosWTableauReset(TS ts)
1129b39943a6SLisandro Dalcin {
1130b39943a6SLisandro Dalcin   TS_RosW        *ros = (TS_RosW*)ts->data;
1131b39943a6SLisandro Dalcin   RosWTableau    tab  = ros->tableau;
1132b39943a6SLisandro Dalcin   PetscErrorCode ierr;
1133b39943a6SLisandro Dalcin 
1134b39943a6SLisandro Dalcin   PetscFunctionBegin;
1135b39943a6SLisandro Dalcin   if (!tab) PetscFunctionReturn(0);
1136b39943a6SLisandro Dalcin   ierr = VecDestroyVecs(tab->s,&ros->Y);CHKERRQ(ierr);
1137b39943a6SLisandro Dalcin   ierr = PetscFree(ros->work);CHKERRQ(ierr);
1138b39943a6SLisandro Dalcin   PetscFunctionReturn(0);
1139b39943a6SLisandro Dalcin }
1140b39943a6SLisandro Dalcin 
1141e27a552bSJed Brown static PetscErrorCode TSReset_RosW(TS ts)
1142e27a552bSJed Brown {
114361692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1144e27a552bSJed Brown   PetscErrorCode ierr;
1145e27a552bSJed Brown 
1146e27a552bSJed Brown   PetscFunctionBegin;
1147b39943a6SLisandro Dalcin   ierr = TSRosWTableauReset(ts);CHKERRQ(ierr);
114861692a83SJed Brown   ierr = VecDestroy(&ros->Ydot);CHKERRQ(ierr);
114961692a83SJed Brown   ierr = VecDestroy(&ros->Ystage);CHKERRQ(ierr);
115061692a83SJed Brown   ierr = VecDestroy(&ros->Zdot);CHKERRQ(ierr);
115161692a83SJed Brown   ierr = VecDestroy(&ros->Zstage);CHKERRQ(ierr);
1152be5899b3SLisandro Dalcin   ierr = VecDestroy(&ros->vec_sol_prev);CHKERRQ(ierr);
1153e27a552bSJed Brown   PetscFunctionReturn(0);
1154e27a552bSJed Brown }
1155e27a552bSJed Brown 
1156d5e6173cSPeter Brune static PetscErrorCode TSRosWGetVecs(TS ts,DM dm,Vec *Ydot,Vec *Zdot,Vec *Ystage,Vec *Zstage)
1157d5e6173cSPeter Brune {
1158d5e6173cSPeter Brune   TS_RosW        *rw = (TS_RosW*)ts->data;
1159d5e6173cSPeter Brune   PetscErrorCode ierr;
1160d5e6173cSPeter Brune 
1161d5e6173cSPeter Brune   PetscFunctionBegin;
1162d5e6173cSPeter Brune   if (Ydot) {
1163d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1164d5e6173cSPeter Brune       ierr = DMGetNamedGlobalVector(dm,"TSRosW_Ydot",Ydot);CHKERRQ(ierr);
1165d5e6173cSPeter Brune     } else *Ydot = rw->Ydot;
1166d5e6173cSPeter Brune   }
1167d5e6173cSPeter Brune   if (Zdot) {
1168d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1169d5e6173cSPeter Brune       ierr = DMGetNamedGlobalVector(dm,"TSRosW_Zdot",Zdot);CHKERRQ(ierr);
1170d5e6173cSPeter Brune     } else *Zdot = rw->Zdot;
1171d5e6173cSPeter Brune   }
1172d5e6173cSPeter Brune   if (Ystage) {
1173d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1174d5e6173cSPeter Brune       ierr = DMGetNamedGlobalVector(dm,"TSRosW_Ystage",Ystage);CHKERRQ(ierr);
1175d5e6173cSPeter Brune     } else *Ystage = rw->Ystage;
1176d5e6173cSPeter Brune   }
1177d5e6173cSPeter Brune   if (Zstage) {
1178d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1179d5e6173cSPeter Brune       ierr = DMGetNamedGlobalVector(dm,"TSRosW_Zstage",Zstage);CHKERRQ(ierr);
1180d5e6173cSPeter Brune     } else *Zstage = rw->Zstage;
1181d5e6173cSPeter Brune   }
1182d5e6173cSPeter Brune   PetscFunctionReturn(0);
1183d5e6173cSPeter Brune }
1184d5e6173cSPeter Brune 
1185d5e6173cSPeter Brune 
1186d5e6173cSPeter Brune static PetscErrorCode TSRosWRestoreVecs(TS ts,DM dm,Vec *Ydot,Vec *Zdot, Vec *Ystage, Vec *Zstage)
1187d5e6173cSPeter Brune {
1188d5e6173cSPeter Brune   PetscErrorCode ierr;
1189d5e6173cSPeter Brune 
1190d5e6173cSPeter Brune   PetscFunctionBegin;
1191d5e6173cSPeter Brune   if (Ydot) {
1192d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1193d5e6173cSPeter Brune       ierr = DMRestoreNamedGlobalVector(dm,"TSRosW_Ydot",Ydot);CHKERRQ(ierr);
1194d5e6173cSPeter Brune     }
1195d5e6173cSPeter Brune   }
1196d5e6173cSPeter Brune   if (Zdot) {
1197d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1198d5e6173cSPeter Brune       ierr = DMRestoreNamedGlobalVector(dm,"TSRosW_Zdot",Zdot);CHKERRQ(ierr);
1199d5e6173cSPeter Brune     }
1200d5e6173cSPeter Brune   }
1201d5e6173cSPeter Brune   if (Ystage) {
1202d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1203d5e6173cSPeter Brune       ierr = DMRestoreNamedGlobalVector(dm,"TSRosW_Ystage",Ystage);CHKERRQ(ierr);
1204d5e6173cSPeter Brune     }
1205d5e6173cSPeter Brune   }
1206d5e6173cSPeter Brune   if (Zstage) {
1207d5e6173cSPeter Brune     if (dm && dm != ts->dm) {
1208d5e6173cSPeter Brune       ierr = DMRestoreNamedGlobalVector(dm,"TSRosW_Zstage",Zstage);CHKERRQ(ierr);
1209d5e6173cSPeter Brune     }
1210d5e6173cSPeter Brune   }
1211d5e6173cSPeter Brune   PetscFunctionReturn(0);
1212d5e6173cSPeter Brune }
1213d5e6173cSPeter Brune 
1214d5e6173cSPeter Brune static PetscErrorCode DMCoarsenHook_TSRosW(DM fine,DM coarse,void *ctx)
1215d5e6173cSPeter Brune {
1216d5e6173cSPeter Brune   PetscFunctionBegin;
1217d5e6173cSPeter Brune   PetscFunctionReturn(0);
1218d5e6173cSPeter Brune }
1219d5e6173cSPeter Brune 
1220d5e6173cSPeter Brune static PetscErrorCode DMRestrictHook_TSRosW(DM fine,Mat restrct,Vec rscale,Mat inject,DM coarse,void *ctx)
1221d5e6173cSPeter Brune {
1222d5e6173cSPeter Brune   TS             ts = (TS)ctx;
1223d5e6173cSPeter Brune   PetscErrorCode ierr;
1224d5e6173cSPeter Brune   Vec            Ydot,Zdot,Ystage,Zstage;
1225d5e6173cSPeter Brune   Vec            Ydotc,Zdotc,Ystagec,Zstagec;
1226d5e6173cSPeter Brune 
1227d5e6173cSPeter Brune   PetscFunctionBegin;
1228d5e6173cSPeter Brune   ierr = TSRosWGetVecs(ts,fine,&Ydot,&Ystage,&Zdot,&Zstage);CHKERRQ(ierr);
1229d5e6173cSPeter Brune   ierr = TSRosWGetVecs(ts,coarse,&Ydotc,&Ystagec,&Zdotc,&Zstagec);CHKERRQ(ierr);
1230d5e6173cSPeter Brune   ierr = MatRestrict(restrct,Ydot,Ydotc);CHKERRQ(ierr);
1231d5e6173cSPeter Brune   ierr = VecPointwiseMult(Ydotc,rscale,Ydotc);CHKERRQ(ierr);
1232d5e6173cSPeter Brune   ierr = MatRestrict(restrct,Ystage,Ystagec);CHKERRQ(ierr);
1233d5e6173cSPeter Brune   ierr = VecPointwiseMult(Ystagec,rscale,Ystagec);CHKERRQ(ierr);
1234d5e6173cSPeter Brune   ierr = MatRestrict(restrct,Zdot,Zdotc);CHKERRQ(ierr);
1235d5e6173cSPeter Brune   ierr = VecPointwiseMult(Zdotc,rscale,Zdotc);CHKERRQ(ierr);
1236d5e6173cSPeter Brune   ierr = MatRestrict(restrct,Zstage,Zstagec);CHKERRQ(ierr);
1237d5e6173cSPeter Brune   ierr = VecPointwiseMult(Zstagec,rscale,Zstagec);CHKERRQ(ierr);
1238d5e6173cSPeter Brune   ierr = TSRosWRestoreVecs(ts,fine,&Ydot,&Ystage,&Zdot,&Zstage);CHKERRQ(ierr);
1239d5e6173cSPeter Brune   ierr = TSRosWRestoreVecs(ts,coarse,&Ydotc,&Ystagec,&Zdotc,&Zstagec);CHKERRQ(ierr);
1240d5e6173cSPeter Brune   PetscFunctionReturn(0);
1241d5e6173cSPeter Brune }
1242d5e6173cSPeter Brune 
1243258e1594SPeter Brune 
1244258e1594SPeter Brune static PetscErrorCode DMSubDomainHook_TSRosW(DM fine,DM coarse,void *ctx)
1245258e1594SPeter Brune {
1246258e1594SPeter Brune   PetscFunctionBegin;
1247258e1594SPeter Brune   PetscFunctionReturn(0);
1248258e1594SPeter Brune }
1249258e1594SPeter Brune 
1250258e1594SPeter Brune static PetscErrorCode DMSubDomainRestrictHook_TSRosW(DM dm,VecScatter gscat,VecScatter lscat,DM subdm,void *ctx)
1251258e1594SPeter Brune {
1252258e1594SPeter Brune   TS             ts = (TS)ctx;
1253258e1594SPeter Brune   PetscErrorCode ierr;
1254258e1594SPeter Brune   Vec            Ydot,Zdot,Ystage,Zstage;
1255258e1594SPeter Brune   Vec            Ydots,Zdots,Ystages,Zstages;
1256258e1594SPeter Brune 
1257258e1594SPeter Brune   PetscFunctionBegin;
1258258e1594SPeter Brune   ierr = TSRosWGetVecs(ts,dm,&Ydot,&Ystage,&Zdot,&Zstage);CHKERRQ(ierr);
1259258e1594SPeter Brune   ierr = TSRosWGetVecs(ts,subdm,&Ydots,&Ystages,&Zdots,&Zstages);CHKERRQ(ierr);
1260258e1594SPeter Brune 
1261258e1594SPeter Brune   ierr = VecScatterBegin(gscat,Ydot,Ydots,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1262258e1594SPeter Brune   ierr = VecScatterEnd(gscat,Ydot,Ydots,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1263258e1594SPeter Brune 
1264258e1594SPeter Brune   ierr = VecScatterBegin(gscat,Ystage,Ystages,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1265258e1594SPeter Brune   ierr = VecScatterEnd(gscat,Ystage,Ystages,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1266258e1594SPeter Brune 
1267258e1594SPeter Brune   ierr = VecScatterBegin(gscat,Zdot,Zdots,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1268258e1594SPeter Brune   ierr = VecScatterEnd(gscat,Zdot,Zdots,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1269258e1594SPeter Brune 
1270258e1594SPeter Brune   ierr = VecScatterBegin(gscat,Zstage,Zstages,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1271258e1594SPeter Brune   ierr = VecScatterEnd(gscat,Zstage,Zstages,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1272258e1594SPeter Brune 
1273258e1594SPeter Brune   ierr = TSRosWRestoreVecs(ts,dm,&Ydot,&Ystage,&Zdot,&Zstage);CHKERRQ(ierr);
1274258e1594SPeter Brune   ierr = TSRosWRestoreVecs(ts,subdm,&Ydots,&Ystages,&Zdots,&Zstages);CHKERRQ(ierr);
1275258e1594SPeter Brune   PetscFunctionReturn(0);
1276258e1594SPeter Brune }
1277258e1594SPeter Brune 
1278e27a552bSJed Brown /*
1279e27a552bSJed Brown   This defines the nonlinear equation that is to be solved with SNES
1280e27a552bSJed Brown   G(U) = F[t0+Theta*dt, U, (U-U0)*shift] = 0
1281e27a552bSJed Brown */
1282f9c1d6abSBarry Smith static PetscErrorCode SNESTSFormFunction_RosW(SNES snes,Vec U,Vec F,TS ts)
1283e27a552bSJed Brown {
128461692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1285e27a552bSJed Brown   PetscErrorCode ierr;
1286d5e6173cSPeter Brune   Vec            Ydot,Zdot,Ystage,Zstage;
1287b296d7d5SJed Brown   PetscReal      shift = ros->scoeff / ts->time_step;
1288d5e6173cSPeter Brune   DM             dm,dmsave;
1289e27a552bSJed Brown 
1290e27a552bSJed Brown   PetscFunctionBegin;
1291d5e6173cSPeter Brune   ierr   = SNESGetDM(snes,&dm);CHKERRQ(ierr);
1292d5e6173cSPeter Brune   ierr   = TSRosWGetVecs(ts,dm,&Ydot,&Zdot,&Ystage,&Zstage);CHKERRQ(ierr);
1293b296d7d5SJed Brown   ierr   = VecWAXPY(Ydot,shift,U,Zdot);CHKERRQ(ierr);    /* Ydot = shift*U + Zdot */
1294f9c1d6abSBarry Smith   ierr   = VecWAXPY(Ystage,1.0,U,Zstage);CHKERRQ(ierr);  /* Ystage = U + Zstage */
1295d5e6173cSPeter Brune   dmsave = ts->dm;
1296d5e6173cSPeter Brune   ts->dm = dm;
1297d5e6173cSPeter Brune   ierr   = TSComputeIFunction(ts,ros->stage_time,Ystage,Ydot,F,PETSC_FALSE);CHKERRQ(ierr);
1298d5e6173cSPeter Brune   ts->dm = dmsave;
1299d5e6173cSPeter Brune   ierr   = TSRosWRestoreVecs(ts,dm,&Ydot,&Zdot,&Ystage,&Zstage);CHKERRQ(ierr);
1300e27a552bSJed Brown   PetscFunctionReturn(0);
1301e27a552bSJed Brown }
1302e27a552bSJed Brown 
1303d1e9a80fSBarry Smith static PetscErrorCode SNESTSFormJacobian_RosW(SNES snes,Vec U,Mat A,Mat B,TS ts)
1304e27a552bSJed Brown {
130561692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1306d5e6173cSPeter Brune   Vec            Ydot,Zdot,Ystage,Zstage;
1307b296d7d5SJed Brown   PetscReal      shift = ros->scoeff / ts->time_step;
1308e27a552bSJed Brown   PetscErrorCode ierr;
1309d5e6173cSPeter Brune   DM             dm,dmsave;
1310e27a552bSJed Brown 
1311e27a552bSJed Brown   PetscFunctionBegin;
131261692a83SJed Brown   /* ros->Ydot and ros->Ystage have already been computed in SNESTSFormFunction_RosW (SNES guarantees this) */
1313d5e6173cSPeter Brune   ierr   = SNESGetDM(snes,&dm);CHKERRQ(ierr);
1314d5e6173cSPeter Brune   ierr   = TSRosWGetVecs(ts,dm,&Ydot,&Zdot,&Ystage,&Zstage);CHKERRQ(ierr);
1315d5e6173cSPeter Brune   dmsave = ts->dm;
1316d5e6173cSPeter Brune   ts->dm = dm;
1317d1e9a80fSBarry Smith   ierr   = TSComputeIJacobian(ts,ros->stage_time,Ystage,Ydot,shift,A,B,PETSC_TRUE);CHKERRQ(ierr);
1318d5e6173cSPeter Brune   ts->dm = dmsave;
1319d5e6173cSPeter Brune   ierr   = TSRosWRestoreVecs(ts,dm,&Ydot,&Zdot,&Ystage,&Zstage);CHKERRQ(ierr);
1320e27a552bSJed Brown   PetscFunctionReturn(0);
1321e27a552bSJed Brown }
1322e27a552bSJed Brown 
1323b39943a6SLisandro Dalcin static PetscErrorCode TSRosWTableauSetUp(TS ts)
1324b39943a6SLisandro Dalcin {
1325b39943a6SLisandro Dalcin   TS_RosW        *ros = (TS_RosW*)ts->data;
1326b39943a6SLisandro Dalcin   RosWTableau    tab  = ros->tableau;
1327b39943a6SLisandro Dalcin   PetscErrorCode ierr;
1328b39943a6SLisandro Dalcin 
1329b39943a6SLisandro Dalcin   PetscFunctionBegin;
1330b39943a6SLisandro Dalcin   ierr = VecDuplicateVecs(ts->vec_sol,tab->s,&ros->Y);CHKERRQ(ierr);
1331b39943a6SLisandro Dalcin   ierr = PetscMalloc1(tab->s,&ros->work);CHKERRQ(ierr);
1332b39943a6SLisandro Dalcin   PetscFunctionReturn(0);
1333b39943a6SLisandro Dalcin }
1334b39943a6SLisandro Dalcin 
1335e27a552bSJed Brown static PetscErrorCode TSSetUp_RosW(TS ts)
1336e27a552bSJed Brown {
133761692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1338e27a552bSJed Brown   PetscErrorCode ierr;
1339d5e6173cSPeter Brune   DM             dm;
1340b39943a6SLisandro Dalcin   SNES           snes;
1341e27a552bSJed Brown 
1342e27a552bSJed Brown   PetscFunctionBegin;
1343b39943a6SLisandro Dalcin   ierr = TSRosWTableauSetUp(ts);CHKERRQ(ierr);
134461692a83SJed Brown   ierr = VecDuplicate(ts->vec_sol,&ros->Ydot);CHKERRQ(ierr);
134561692a83SJed Brown   ierr = VecDuplicate(ts->vec_sol,&ros->Ystage);CHKERRQ(ierr);
134661692a83SJed Brown   ierr = VecDuplicate(ts->vec_sol,&ros->Zdot);CHKERRQ(ierr);
134761692a83SJed Brown   ierr = VecDuplicate(ts->vec_sol,&ros->Zstage);CHKERRQ(ierr);
1348be5899b3SLisandro Dalcin   ierr = VecDuplicate(ts->vec_sol,&ros->vec_sol_prev);CHKERRQ(ierr);
134922d28d08SBarry Smith   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1350d5e6173cSPeter Brune   ierr = DMCoarsenHookAdd(dm,DMCoarsenHook_TSRosW,DMRestrictHook_TSRosW,ts);CHKERRQ(ierr);
1351258e1594SPeter Brune   ierr = DMSubDomainHookAdd(dm,DMSubDomainHook_TSRosW,DMSubDomainRestrictHook_TSRosW,ts);CHKERRQ(ierr);
1352b39943a6SLisandro Dalcin   /* Rosenbrock methods are linearly implicit, so set that unless the user has specifically asked for something else */
1353b39943a6SLisandro Dalcin   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1354b39943a6SLisandro Dalcin   if (!((PetscObject)snes)->type_name) {
1355b39943a6SLisandro Dalcin     ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);
1356b39943a6SLisandro Dalcin   }
1357e27a552bSJed Brown   PetscFunctionReturn(0);
1358e27a552bSJed Brown }
1359e27a552bSJed Brown /*------------------------------------------------------------*/
1360e27a552bSJed Brown 
13614416b707SBarry Smith static PetscErrorCode TSSetFromOptions_RosW(PetscOptionItems *PetscOptionsObject,TS ts)
1362e27a552bSJed Brown {
136361692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1364e27a552bSJed Brown   PetscErrorCode ierr;
1365b39943a6SLisandro Dalcin   SNES           snes;
1366e27a552bSJed Brown 
1367e27a552bSJed Brown   PetscFunctionBegin;
1368e55864a3SBarry Smith   ierr = PetscOptionsHead(PetscOptionsObject,"RosW ODE solver options");CHKERRQ(ierr);
1369e27a552bSJed Brown   {
137061692a83SJed Brown     RosWTableauLink link;
1371e27a552bSJed Brown     PetscInt        count,choice;
1372e27a552bSJed Brown     PetscBool       flg;
1373e27a552bSJed Brown     const char      **namelist;
137461692a83SJed Brown 
137561692a83SJed Brown     for (link=RosWTableauList,count=0; link; link=link->next,count++) ;
1376f489ac74SBarry Smith     ierr = PetscMalloc1(count,(char***)&namelist);CHKERRQ(ierr);
137761692a83SJed Brown     for (link=RosWTableauList,count=0; link; link=link->next,count++) namelist[count] = link->tab.name;
1378b39943a6SLisandro Dalcin     ierr = PetscOptionsEList("-ts_rosw_type","Family of Rosenbrock-W method","TSRosWSetType",(const char*const*)namelist,count,ros->tableau->name,&choice,&flg);CHKERRQ(ierr);
1379b39943a6SLisandro Dalcin     if (flg) {ierr = TSRosWSetType(ts,namelist[choice]);CHKERRQ(ierr);}
1380e27a552bSJed Brown     ierr = PetscFree(namelist);CHKERRQ(ierr);
138161692a83SJed Brown 
13820298fd71SBarry Smith     ierr = PetscOptionsBool("-ts_rosw_recompute_jacobian","Recompute the Jacobian at each stage","TSRosWSetRecomputeJacobian",ros->recompute_jacobian,&ros->recompute_jacobian,NULL);CHKERRQ(ierr);
1383b39943a6SLisandro Dalcin   }
1384b39943a6SLisandro Dalcin   ierr = PetscOptionsTail();CHKERRQ(ierr);
138561692a83SJed Brown   /* Rosenbrock methods are linearly implicit, so set that unless the user has specifically asked for something else */
138661692a83SJed Brown   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
138761692a83SJed Brown   if (!((PetscObject)snes)->type_name) {
138861692a83SJed Brown     ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);
138961692a83SJed Brown   }
1390e27a552bSJed Brown   PetscFunctionReturn(0);
1391e27a552bSJed Brown }
1392e27a552bSJed Brown 
1393e27a552bSJed Brown static PetscErrorCode TSView_RosW(TS ts,PetscViewer viewer)
1394e27a552bSJed Brown {
139561692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1396e27a552bSJed Brown   PetscBool      iascii;
1397e27a552bSJed Brown   PetscErrorCode ierr;
1398e27a552bSJed Brown 
1399e27a552bSJed Brown   PetscFunctionBegin;
1400251f4c67SDmitry Karpeev   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1401e27a552bSJed Brown   if (iascii) {
14029c334d8fSLisandro Dalcin     RosWTableau tab  = ros->tableau;
140319fd82e9SBarry Smith     TSRosWType  rostype;
14049c334d8fSLisandro Dalcin     char        buf[512];
1405e408995aSJed Brown     PetscInt    i;
1406e408995aSJed Brown     PetscReal   abscissa[512];
140761692a83SJed Brown     ierr = TSRosWGetType(ts,&rostype);CHKERRQ(ierr);
140861692a83SJed Brown     ierr = PetscViewerASCIIPrintf(viewer,"  Rosenbrock-W %s\n",rostype);CHKERRQ(ierr);
1409de043e34SBarry Smith     ierr = PetscFormatRealArray(buf,sizeof(buf),"% 8.6f",tab->s,tab->ASum);CHKERRQ(ierr);
141061692a83SJed Brown     ierr = PetscViewerASCIIPrintf(viewer,"  Abscissa of A       = %s\n",buf);CHKERRQ(ierr);
1411e408995aSJed Brown     for (i=0; i<tab->s; i++) abscissa[i] = tab->ASum[i] + tab->Gamma[i];
1412de043e34SBarry Smith     ierr = PetscFormatRealArray(buf,sizeof(buf),"% 8.6f",tab->s,abscissa);CHKERRQ(ierr);
1413e408995aSJed Brown     ierr = PetscViewerASCIIPrintf(viewer,"  Abscissa of A+Gamma = %s\n",buf);CHKERRQ(ierr);
1414e27a552bSJed Brown   }
1415e27a552bSJed Brown   PetscFunctionReturn(0);
1416e27a552bSJed Brown }
1417e27a552bSJed Brown 
14189200755eSBarry Smith static PetscErrorCode TSLoad_RosW(TS ts,PetscViewer viewer)
14199200755eSBarry Smith {
14209200755eSBarry Smith   PetscErrorCode ierr;
14219200755eSBarry Smith   SNES           snes;
14229c334d8fSLisandro Dalcin   TSAdapt        adapt;
14239200755eSBarry Smith 
14249200755eSBarry Smith   PetscFunctionBegin;
14259c334d8fSLisandro Dalcin   ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
14269c334d8fSLisandro Dalcin   ierr = TSAdaptLoad(adapt,viewer);CHKERRQ(ierr);
14279200755eSBarry Smith   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
14289200755eSBarry Smith   ierr = SNESLoad(snes,viewer);CHKERRQ(ierr);
14299200755eSBarry Smith   /* function and Jacobian context for SNES when used with TS is always ts object */
14309200755eSBarry Smith   ierr = SNESSetFunction(snes,NULL,NULL,ts);CHKERRQ(ierr);
14319200755eSBarry Smith   ierr = SNESSetJacobian(snes,NULL,NULL,NULL,ts);CHKERRQ(ierr);
14329200755eSBarry Smith   PetscFunctionReturn(0);
14339200755eSBarry Smith }
14349200755eSBarry Smith 
1435e27a552bSJed Brown /*@C
143661692a83SJed Brown   TSRosWSetType - Set the type of Rosenbrock-W scheme
1437e27a552bSJed Brown 
1438e27a552bSJed Brown   Logically collective
1439e27a552bSJed Brown 
1440e27a552bSJed Brown   Input Parameter:
1441e27a552bSJed Brown +  ts - timestepping context
1442b92453a8SLisandro Dalcin -  roswtype - type of Rosenbrock-W scheme
1443e27a552bSJed Brown 
1444020d8f30SJed Brown   Level: beginner
1445e27a552bSJed Brown 
1446020d8f30SJed Brown .seealso: TSRosWGetType(), TSROSW, TSROSW2M, TSROSW2P, TSROSWRA3PW, TSROSWRA34PW2, TSROSWRODAS3, TSROSWSANDU3, TSROSWASSP3P3S1C, TSROSWLASSP3P4S2C, TSROSWLLSSP3P4S2C, TSROSWARK3
1447e27a552bSJed Brown @*/
1448b92453a8SLisandro Dalcin PetscErrorCode TSRosWSetType(TS ts,TSRosWType roswtype)
1449e27a552bSJed Brown {
1450e27a552bSJed Brown   PetscErrorCode ierr;
1451e27a552bSJed Brown 
1452e27a552bSJed Brown   PetscFunctionBegin;
1453e27a552bSJed Brown   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1454b92453a8SLisandro Dalcin   PetscValidCharPointer(roswtype,2);
1455b92453a8SLisandro Dalcin   ierr = PetscTryMethod(ts,"TSRosWSetType_C",(TS,TSRosWType),(ts,roswtype));CHKERRQ(ierr);
1456e27a552bSJed Brown   PetscFunctionReturn(0);
1457e27a552bSJed Brown }
1458e27a552bSJed Brown 
1459e27a552bSJed Brown /*@C
146061692a83SJed Brown   TSRosWGetType - Get the type of Rosenbrock-W scheme
1461e27a552bSJed Brown 
1462e27a552bSJed Brown   Logically collective
1463e27a552bSJed Brown 
1464e27a552bSJed Brown   Input Parameter:
1465e27a552bSJed Brown .  ts - timestepping context
1466e27a552bSJed Brown 
1467e27a552bSJed Brown   Output Parameter:
146861692a83SJed Brown .  rostype - type of Rosenbrock-W scheme
1469e27a552bSJed Brown 
1470e27a552bSJed Brown   Level: intermediate
1471e27a552bSJed Brown 
1472e27a552bSJed Brown .seealso: TSRosWGetType()
1473e27a552bSJed Brown @*/
147419fd82e9SBarry Smith PetscErrorCode TSRosWGetType(TS ts,TSRosWType *rostype)
1475e27a552bSJed Brown {
1476e27a552bSJed Brown   PetscErrorCode ierr;
1477e27a552bSJed Brown 
1478e27a552bSJed Brown   PetscFunctionBegin;
1479e27a552bSJed Brown   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
148019fd82e9SBarry Smith   ierr = PetscUseMethod(ts,"TSRosWGetType_C",(TS,TSRosWType*),(ts,rostype));CHKERRQ(ierr);
1481e27a552bSJed Brown   PetscFunctionReturn(0);
1482e27a552bSJed Brown }
1483e27a552bSJed Brown 
1484e27a552bSJed Brown /*@C
148561692a83SJed Brown   TSRosWSetRecomputeJacobian - Set whether to recompute the Jacobian at each stage. The default is to update the Jacobian once per step.
1486e27a552bSJed Brown 
1487e27a552bSJed Brown   Logically collective
1488e27a552bSJed Brown 
1489e27a552bSJed Brown   Input Parameter:
1490e27a552bSJed Brown +  ts - timestepping context
149161692a83SJed Brown -  flg - PETSC_TRUE to recompute the Jacobian at each stage
1492e27a552bSJed Brown 
1493e27a552bSJed Brown   Level: intermediate
1494e27a552bSJed Brown 
1495e27a552bSJed Brown .seealso: TSRosWGetType()
1496e27a552bSJed Brown @*/
149761692a83SJed Brown PetscErrorCode TSRosWSetRecomputeJacobian(TS ts,PetscBool flg)
1498e27a552bSJed Brown {
1499e27a552bSJed Brown   PetscErrorCode ierr;
1500e27a552bSJed Brown 
1501e27a552bSJed Brown   PetscFunctionBegin;
1502e27a552bSJed Brown   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
150361692a83SJed Brown   ierr = PetscTryMethod(ts,"TSRosWSetRecomputeJacobian_C",(TS,PetscBool),(ts,flg));CHKERRQ(ierr);
1504e27a552bSJed Brown   PetscFunctionReturn(0);
1505e27a552bSJed Brown }
1506e27a552bSJed Brown 
1507560360afSLisandro Dalcin static PetscErrorCode  TSRosWGetType_RosW(TS ts,TSRosWType *rostype)
1508e27a552bSJed Brown {
150961692a83SJed Brown   TS_RosW        *ros = (TS_RosW*)ts->data;
1510e27a552bSJed Brown 
1511e27a552bSJed Brown   PetscFunctionBegin;
151261692a83SJed Brown   *rostype = ros->tableau->name;
1513e27a552bSJed Brown   PetscFunctionReturn(0);
1514e27a552bSJed Brown }
1515ef20d060SBarry Smith 
1516560360afSLisandro Dalcin static PetscErrorCode  TSRosWSetType_RosW(TS ts,TSRosWType rostype)
1517e27a552bSJed Brown {
151861692a83SJed Brown   TS_RosW         *ros = (TS_RosW*)ts->data;
1519e27a552bSJed Brown   PetscErrorCode  ierr;
1520e27a552bSJed Brown   PetscBool       match;
152161692a83SJed Brown   RosWTableauLink link;
1522e27a552bSJed Brown 
1523e27a552bSJed Brown   PetscFunctionBegin;
152461692a83SJed Brown   if (ros->tableau) {
152561692a83SJed Brown     ierr = PetscStrcmp(ros->tableau->name,rostype,&match);CHKERRQ(ierr);
1526e27a552bSJed Brown     if (match) PetscFunctionReturn(0);
1527e27a552bSJed Brown   }
152861692a83SJed Brown   for (link = RosWTableauList; link; link=link->next) {
152961692a83SJed Brown     ierr = PetscStrcmp(link->tab.name,rostype,&match);CHKERRQ(ierr);
1530e27a552bSJed Brown     if (match) {
1531b39943a6SLisandro Dalcin       if (ts->setupcalled) {ierr = TSRosWTableauReset(ts);CHKERRQ(ierr);}
153261692a83SJed Brown       ros->tableau = &link->tab;
1533b39943a6SLisandro Dalcin       if (ts->setupcalled) {ierr = TSRosWTableauSetUp(ts);CHKERRQ(ierr);}
15342ffb9264SLisandro Dalcin       ts->default_adapt_type = ros->tableau->bembed ? TSADAPTBASIC : TSADAPTNONE;
1535e27a552bSJed Brown       PetscFunctionReturn(0);
1536e27a552bSJed Brown     }
1537e27a552bSJed Brown   }
1538ce94432eSBarry Smith   SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_UNKNOWN_TYPE,"Could not find '%s'",rostype);
1539e27a552bSJed Brown   PetscFunctionReturn(0);
1540e27a552bSJed Brown }
154161692a83SJed Brown 
1542560360afSLisandro Dalcin static PetscErrorCode  TSRosWSetRecomputeJacobian_RosW(TS ts,PetscBool flg)
1543e27a552bSJed Brown {
154461692a83SJed Brown   TS_RosW *ros = (TS_RosW*)ts->data;
1545e27a552bSJed Brown 
1546e27a552bSJed Brown   PetscFunctionBegin;
154761692a83SJed Brown   ros->recompute_jacobian = flg;
1548e27a552bSJed Brown   PetscFunctionReturn(0);
1549e27a552bSJed Brown }
1550e27a552bSJed Brown 
1551b3a6b972SJed Brown static PetscErrorCode TSDestroy_RosW(TS ts)
1552b3a6b972SJed Brown {
1553b3a6b972SJed Brown   PetscErrorCode ierr;
1554b3a6b972SJed Brown 
1555b3a6b972SJed Brown   PetscFunctionBegin;
1556b3a6b972SJed Brown   ierr = TSReset_RosW(ts);CHKERRQ(ierr);
1557b3a6b972SJed Brown   if (ts->dm) {
1558b3a6b972SJed Brown     ierr = DMCoarsenHookRemove(ts->dm,DMCoarsenHook_TSRosW,DMRestrictHook_TSRosW,ts);CHKERRQ(ierr);
1559b3a6b972SJed Brown     ierr = DMSubDomainHookRemove(ts->dm,DMSubDomainHook_TSRosW,DMSubDomainRestrictHook_TSRosW,ts);CHKERRQ(ierr);
1560b3a6b972SJed Brown   }
1561b3a6b972SJed Brown   ierr = PetscFree(ts->data);CHKERRQ(ierr);
1562b3a6b972SJed Brown   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWGetType_C",NULL);CHKERRQ(ierr);
1563b3a6b972SJed Brown   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWSetType_C",NULL);CHKERRQ(ierr);
1564b3a6b972SJed Brown   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWSetRecomputeJacobian_C",NULL);CHKERRQ(ierr);
1565b3a6b972SJed Brown   PetscFunctionReturn(0);
1566b3a6b972SJed Brown }
1567d5e6173cSPeter Brune 
1568e27a552bSJed Brown /* ------------------------------------------------------------ */
1569e27a552bSJed Brown /*MC
1570020d8f30SJed Brown       TSROSW - ODE solver using Rosenbrock-W schemes
1571e27a552bSJed Brown 
1572e27a552bSJed Brown   These methods are intended for problems with well-separated time scales, especially when a slow scale is strongly
1573e27a552bSJed Brown   nonlinear such that it is expensive to solve with a fully implicit method. The user should provide the stiff part
1574e27a552bSJed Brown   of the equation using TSSetIFunction() and the non-stiff part with TSSetRHSFunction().
1575e27a552bSJed Brown 
1576e27a552bSJed Brown   Notes:
157761692a83SJed Brown   This method currently only works with autonomous ODE and DAE.
157861692a83SJed Brown 
1579d0685a90SJed Brown   Consider trying TSARKIMEX if the stiff part is strongly nonlinear.
1580d0685a90SJed Brown 
1581*3d5a8a6aSBarry Smith   Since this uses a single linear solve per time-step if you wish to lag the jacobian or preconditioner computation you must use also -snes_lag_jacobian_persists true or -snes_lag_jacobian_preconditioner true
1582*3d5a8a6aSBarry Smith 
1583e94cfbe0SPatrick Sanan   Developer Notes:
158461692a83SJed Brown   Rosenbrock-W methods are typically specified for autonomous ODE
158561692a83SJed Brown 
1586f9c1d6abSBarry Smith $  udot = f(u)
158761692a83SJed Brown 
158861692a83SJed Brown   by the stage equations
158961692a83SJed Brown 
1590f9c1d6abSBarry Smith $  k_i = h f(u_0 + sum_j alpha_ij k_j) + h J sum_j gamma_ij k_j
159161692a83SJed Brown 
159261692a83SJed Brown   and step completion formula
159361692a83SJed Brown 
1594f9c1d6abSBarry Smith $  u_1 = u_0 + sum_j b_j k_j
159561692a83SJed Brown 
1596f9c1d6abSBarry Smith   with step size h and coefficients alpha_ij, gamma_ij, and b_i. Implementing the method in this form would require f(u)
159761692a83SJed Brown   and the Jacobian J to be available, in addition to the shifted matrix I - h gamma_ii J. Following Hairer and Wanner,
159861692a83SJed Brown   we define new variables for the stage equations
159961692a83SJed Brown 
160061692a83SJed Brown $  y_i = gamma_ij k_j
160161692a83SJed Brown 
160261692a83SJed Brown   The k_j can be recovered because Gamma is invertible. Let C be the lower triangular part of Gamma^{-1} and define
160361692a83SJed Brown 
1604b70472e2SJed Brown $  A = Alpha Gamma^{-1}, bt^T = b^T Gamma^{-1}
160561692a83SJed Brown 
160661692a83SJed Brown   to rewrite the method as
160761692a83SJed Brown 
1608f9c1d6abSBarry Smith $  [M/(h gamma_ii) - J] y_i = f(u_0 + sum_j a_ij y_j) + M sum_j (c_ij/h) y_j
1609f9c1d6abSBarry Smith $  u_1 = u_0 + sum_j bt_j y_j
161061692a83SJed Brown 
161161692a83SJed Brown    where we have introduced the mass matrix M. Continue by defining
161261692a83SJed Brown 
161361692a83SJed Brown $  ydot_i = 1/(h gamma_ii) y_i - sum_j (c_ij/h) y_j
161461692a83SJed Brown 
161561692a83SJed Brown    or, more compactly in tensor notation
161661692a83SJed Brown 
161761692a83SJed Brown $  Ydot = 1/h (Gamma^{-1} \otimes I) Y .
161861692a83SJed Brown 
161961692a83SJed Brown    Note that Gamma^{-1} is lower triangular. With this definition of Ydot in terms of known quantities and the current
162061692a83SJed Brown    stage y_i, the stage equations reduce to performing one Newton step (typically with a lagged Jacobian) on the
162161692a83SJed Brown    equation
162261692a83SJed Brown 
1623f9c1d6abSBarry Smith $  g(u_0 + sum_j a_ij y_j + y_i, ydot_i) = 0
162461692a83SJed Brown 
162561692a83SJed Brown    with initial guess y_i = 0.
1626e27a552bSJed Brown 
1627e27a552bSJed Brown   Level: beginner
1628e27a552bSJed Brown 
1629d0685a90SJed Brown .seealso:  TSCreate(), TS, TSSetType(), TSRosWSetType(), TSRosWRegister(), TSROSWTHETA1, TSROSWTHETA2, TSROSW2M, TSROSW2P, TSROSWRA3PW, TSROSWRA34PW2, TSROSWRODAS3,
1630a4386c9eSJed Brown            TSROSWSANDU3, TSROSWASSP3P3S1C, TSROSWLASSP3P4S2C, TSROSWLLSSP3P4S2C, TSROSWGRK4T, TSROSWSHAMP4, TSROSWVELDD4, TSROSW4L
1631e27a552bSJed Brown M*/
16328cc058d9SJed Brown PETSC_EXTERN PetscErrorCode TSCreate_RosW(TS ts)
1633e27a552bSJed Brown {
163461692a83SJed Brown   TS_RosW        *ros;
1635e27a552bSJed Brown   PetscErrorCode ierr;
1636e27a552bSJed Brown 
1637e27a552bSJed Brown   PetscFunctionBegin;
1638607a6623SBarry Smith   ierr = TSRosWInitializePackage();CHKERRQ(ierr);
1639e27a552bSJed Brown 
1640e27a552bSJed Brown   ts->ops->reset          = TSReset_RosW;
1641e27a552bSJed Brown   ts->ops->destroy        = TSDestroy_RosW;
1642e27a552bSJed Brown   ts->ops->view           = TSView_RosW;
16439200755eSBarry Smith   ts->ops->load           = TSLoad_RosW;
1644e27a552bSJed Brown   ts->ops->setup          = TSSetUp_RosW;
1645e27a552bSJed Brown   ts->ops->step           = TSStep_RosW;
1646e27a552bSJed Brown   ts->ops->interpolate    = TSInterpolate_RosW;
16471c3436cfSJed Brown   ts->ops->evaluatestep   = TSEvaluateStep_RosW;
164824655328SShri   ts->ops->rollback       = TSRollBack_RosW;
1649e27a552bSJed Brown   ts->ops->setfromoptions = TSSetFromOptions_RosW;
1650e27a552bSJed Brown   ts->ops->snesfunction   = SNESTSFormFunction_RosW;
1651e27a552bSJed Brown   ts->ops->snesjacobian   = SNESTSFormJacobian_RosW;
1652e27a552bSJed Brown 
1653efd4aadfSBarry Smith   ts->usessnes = PETSC_TRUE;
1654efd4aadfSBarry Smith 
1655b00a9115SJed Brown   ierr = PetscNewLog(ts,&ros);CHKERRQ(ierr);
165661692a83SJed Brown   ts->data = (void*)ros;
1657e27a552bSJed Brown 
1658bdf89e91SBarry Smith   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWGetType_C",TSRosWGetType_RosW);CHKERRQ(ierr);
1659bdf89e91SBarry Smith   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWSetType_C",TSRosWSetType_RosW);CHKERRQ(ierr);
1660bdf89e91SBarry Smith   ierr = PetscObjectComposeFunction((PetscObject)ts,"TSRosWSetRecomputeJacobian_C",TSRosWSetRecomputeJacobian_RosW);CHKERRQ(ierr);
1661b39943a6SLisandro Dalcin 
1662b39943a6SLisandro Dalcin   ierr = TSRosWSetType(ts,TSRosWDefault);CHKERRQ(ierr);
1663e27a552bSJed Brown   PetscFunctionReturn(0);
1664e27a552bSJed Brown }
1665