xref: /petsc/src/dm/dt/tests/ex2.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1*c4762a1bSJed Brown static char help[] = "Tests 1D cell-based discretization tools.\n\n";
2*c4762a1bSJed Brown 
3*c4762a1bSJed Brown #include <petscdt.h>
4*c4762a1bSJed Brown #include <petscviewer.h>
5*c4762a1bSJed Brown 
6*c4762a1bSJed Brown int main(int argc,char **argv)
7*c4762a1bSJed Brown {
8*c4762a1bSJed Brown   PetscErrorCode ierr;
9*c4762a1bSJed Brown   PetscInt       i,j,degrees[1000],ndegrees,nsrc_points,ntarget_points;
10*c4762a1bSJed Brown   PetscReal      src_points[1000],target_points[1000],*R;
11*c4762a1bSJed Brown   PetscBool      flg;
12*c4762a1bSJed Brown 
13*c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
14*c4762a1bSJed Brown   ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Discretization tools test options",NULL);CHKERRQ(ierr);
15*c4762a1bSJed Brown   {
16*c4762a1bSJed Brown     ndegrees   = 1000;
17*c4762a1bSJed Brown     degrees[0] = 1;
18*c4762a1bSJed Brown     degrees[1] = 2;
19*c4762a1bSJed Brown     degrees[2] = 3;
20*c4762a1bSJed Brown     ierr = PetscOptionsIntArray("-degrees","list of max degrees to evaluate","",degrees,&ndegrees,&flg);CHKERRQ(ierr);
21*c4762a1bSJed Brown     if (!flg) ndegrees = 3;
22*c4762a1bSJed Brown 
23*c4762a1bSJed Brown     nsrc_points   = 1000;
24*c4762a1bSJed Brown     src_points[0] = -1.;
25*c4762a1bSJed Brown     src_points[1] = 0.;
26*c4762a1bSJed Brown     src_points[2] = 1.;
27*c4762a1bSJed Brown     ierr = PetscOptionsRealArray("-src_points","list of points defining intervals on which to integrate","",src_points,&nsrc_points,&flg);CHKERRQ(ierr);
28*c4762a1bSJed Brown     if (!flg) nsrc_points = 3;
29*c4762a1bSJed Brown 
30*c4762a1bSJed Brown     ntarget_points   = 1000;
31*c4762a1bSJed Brown     target_points[0] = -1.;
32*c4762a1bSJed Brown     target_points[1] = 0.;
33*c4762a1bSJed Brown     target_points[2] = 1.;
34*c4762a1bSJed Brown     ierr = PetscOptionsRealArray("-target_points","list of points defining intervals on which to integrate","",target_points,&ntarget_points,&flg);CHKERRQ(ierr);
35*c4762a1bSJed Brown     if (!flg) ntarget_points = 3;
36*c4762a1bSJed Brown   }
37*c4762a1bSJed Brown   ierr = PetscOptionsEnd();CHKERRQ(ierr);
38*c4762a1bSJed Brown 
39*c4762a1bSJed Brown   ierr = PetscMalloc1((nsrc_points-1)*(ntarget_points-1),&R);CHKERRQ(ierr);
40*c4762a1bSJed Brown   for (i=0; i<ndegrees; i++) {
41*c4762a1bSJed Brown     ierr = PetscDTReconstructPoly(degrees[i],nsrc_points-1,src_points,ntarget_points-1,target_points,R);CHKERRQ(ierr);
42*c4762a1bSJed Brown     for (j=0; j<(ntarget_points-1)*(nsrc_points-1); j++) { /* Truncate to zero for nicer output */
43*c4762a1bSJed Brown       if (PetscAbs(R[j]) < 10*PETSC_MACHINE_EPSILON) R[j] = 0;
44*c4762a1bSJed Brown     }
45*c4762a1bSJed Brown     for (j=0; j<ntarget_points-1; j++) {
46*c4762a1bSJed Brown       ierr = PetscPrintf(PETSC_COMM_WORLD,"Degree %D target interval (%g,%g)\n",degrees[i],(double)target_points[j],(double)target_points[j+1]);CHKERRQ(ierr);
47*c4762a1bSJed Brown       ierr = PetscRealView(nsrc_points-1,R+j*(nsrc_points-1),PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
48*c4762a1bSJed Brown     }
49*c4762a1bSJed Brown   }
50*c4762a1bSJed Brown   ierr = PetscFree(R);CHKERRQ(ierr);
51*c4762a1bSJed Brown   ierr = PetscFinalize();
52*c4762a1bSJed Brown   return ierr;
53*c4762a1bSJed Brown }
54*c4762a1bSJed Brown 
55*c4762a1bSJed Brown /*TEST
56*c4762a1bSJed Brown   test:
57*c4762a1bSJed Brown     suffix: 1
58*c4762a1bSJed Brown     args: -degrees 1,2,3 -target_points -0.3,0,.2 -src_points -1,-.3,0,.2,1
59*c4762a1bSJed Brown TEST*/
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