impls/pounders/gqt.c

4 static PetscErrorCode estsv(PetscInt n, PetscReal *r, PetscInt ldr, PetscReal *svmin, PetscReal *z)
12   PetscCall(PetscBLASIntCast(ldr, &blasldr));
25       if (PetscAbs(e - z[i]) > PetscAbs(r[i + ldr * i])) {
26         temp = PetscMin(0.01, PetscAbs(r[i + ldr * i])) / PetscAbs(e - z[i]);
32       if (r[i + ldr * i] == 0.0) {
35         w  = (e - z[i]) / r[i + ldr * i];
36         wm = -(e + z[i]) / r[i + ldr * i];
42       for (j = i + 1; j < n; j++) sm += PetscAbs(z[j] + wm * r[i + ldr * j]);
45         PetscCallBLAS("BLASaxpy", BLASaxpy_(&blasnmi, &w, &r[i + ldr * (i + 1)], &blasldr, &z[i + 1], &blas1));
51         if (i < n - 1) PetscCallBLAS("BLASaxpy", BLASaxpy_(&blasnmi, &temp, &r[i + ldr * (i + 1)], &blasldr, &z[i + 1], &blas1));
61       if (PetscAbs(z[j]) > PetscAbs(r[j + ldr * j])) {
62         temp = PetscMin(0.01, PetscAbs(r[j + ldr * j] / z[j]));
66       if (r[j + ldr * j] == 0) {
69         z[j] = z[j] / r[j + ldr * j];
73       PetscCallBLAS("BLASaxpy", BLASaxpy_(&blasj, &temp, &r[0 + ldr * j], &blas1, z, &blas1));