Actual source code: ex1.c
2: static char help[] = "Basic vector routines.\n\n";
4: /*T
5: Concepts: vectors^basic routines;
6: Processors: n
7: T*/
11: /*
12: Include "petscvec.h" so that we can use vectors. Note that this file
13: automatically includes:
14: petscsys.h - base PETSc routines petscis.h - index sets
15: petscviewer.h - viewers
16: */
18: #include <petscvec.h>
20: int main(int argc,char **argv)
21: {
22: Vec x,y,w; /* vectors */
23: Vec *z; /* array of vectors */
24: PetscReal norm,v,v1,v2,maxval;
25: PetscInt n = 20,maxind;
27: PetscScalar one = 1.0,two = 2.0,three = 3.0,dots[3],dot;
29: PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
30: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
32: /*
33: Create a vector, specifying only its global dimension.
34: When using VecCreate(), VecSetSizes() and VecSetFromOptions(), the vector format
35: (currently parallel, shared, or sequential) is determined at runtime. Also, the
36: parallel partitioning of the vector is determined by PETSc at runtime.
38: Routines for creating particular vector types directly are:
39: VecCreateSeq() - uniprocessor vector
40: VecCreateMPI() - distributed vector, where the user can
41: determine the parallel partitioning
42: VecCreateShared() - parallel vector that uses shared memory
43: (available only on the SGI); otherwise,
44: is the same as VecCreateMPI()
46: With VecCreate(), VecSetSizes() and VecSetFromOptions() the option -vec_type mpi or
47: -vec_type shared causes the particular type of vector to be formed.
49: */
50: VecCreate(PETSC_COMM_WORLD,&x);
51: VecSetSizes(x,PETSC_DECIDE,n);
52: VecSetFromOptions(x);
54: /*
55: Duplicate some work vectors (of the same format and
56: partitioning as the initial vector).
57: */
58: VecDuplicate(x,&y);
59: VecDuplicate(x,&w);
61: /*
62: Duplicate more work vectors (of the same format and
63: partitioning as the initial vector). Here we duplicate
64: an array of vectors, which is often more convenient than
65: duplicating individual ones.
66: */
67: VecDuplicateVecs(x,3,&z);
68: /*
69: Set the vectors to entries to a constant value.
70: */
71: VecSet(x,one);
72: VecSet(y,two);
73: VecSet(z[0],one);
74: VecSet(z[1],two);
75: VecSet(z[2],three);
76: /*
77: Demonstrate various basic vector routines.
78: */
79: VecDot(x,y,&dot);
80: VecMDot(x,3,z,dots);
82: /*
83: Note: If using a complex numbers version of PETSc, then
84: PETSC_USE_COMPLEX is defined in the makefiles; otherwise,
85: (when using real numbers) it is undefined.
86: */
88: PetscPrintf(PETSC_COMM_WORLD,"Vector length %D\n",n);
89: VecMax(x,&maxind,&maxval);
90: PetscPrintf(PETSC_COMM_WORLD,"VecMax %g, VecInd %D\n",(double)maxval,maxind);
92: VecMin(x,&maxind,&maxval);
93: PetscPrintf(PETSC_COMM_WORLD,"VecMin %g, VecInd %D\n",(double)maxval,maxind);
94: PetscPrintf(PETSC_COMM_WORLD,"All other values should be near zero\n");
97: VecScale(x,two);
98: VecNorm(x,NORM_2,&norm);
99: v = norm-2.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
100: PetscPrintf(PETSC_COMM_WORLD,"VecScale %g\n",(double)v);
103: VecCopy(x,w);
104: VecNorm(w,NORM_2,&norm);
105: v = norm-2.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
106: PetscPrintf(PETSC_COMM_WORLD,"VecCopy %g\n",(double)v);
108: VecAXPY(y,three,x);
109: VecNorm(y,NORM_2,&norm);
110: v = norm-8.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
111: PetscPrintf(PETSC_COMM_WORLD,"VecAXPY %g\n",(double)v);
113: VecAYPX(y,two,x);
114: VecNorm(y,NORM_2,&norm);
115: v = norm-18.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
116: PetscPrintf(PETSC_COMM_WORLD,"VecAYPX %g\n",(double)v);
118: VecSwap(x,y);
119: VecNorm(y,NORM_2,&norm);
120: v = norm-2.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
121: PetscPrintf(PETSC_COMM_WORLD,"VecSwap %g\n",(double)v);
122: VecNorm(x,NORM_2,&norm);
123: v = norm-18.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
124: PetscPrintf(PETSC_COMM_WORLD,"VecSwap %g\n",(double)v);
126: VecWAXPY(w,two,x,y);
127: VecNorm(w,NORM_2,&norm);
128: v = norm-38.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
129: PetscPrintf(PETSC_COMM_WORLD,"VecWAXPY %g\n",(double)v);
131: VecPointwiseMult(w,y,x);
132: VecNorm(w,NORM_2,&norm);
133: v = norm-36.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
134: PetscPrintf(PETSC_COMM_WORLD,"VecPointwiseMult %g\n",(double)v);
136: VecPointwiseDivide(w,x,y);
137: VecNorm(w,NORM_2,&norm);
138: v = norm-9.0*PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
139: PetscPrintf(PETSC_COMM_WORLD,"VecPointwiseDivide %g\n",(double)v);
141: dots[0] = one;
142: dots[1] = three;
143: dots[2] = two;
145: VecSet(x,one);
146: VecMAXPY(x,3,dots,z);
147: VecNorm(z[0],NORM_2,&norm);
148: v = norm-PetscSqrtReal((PetscReal)n); if (v > -PETSC_SMALL && v < PETSC_SMALL) v = 0.0;
149: VecNorm(z[1],NORM_2,&norm);
150: v1 = norm-2.0*PetscSqrtReal((PetscReal)n); if (v1 > -PETSC_SMALL && v1 < PETSC_SMALL) v1 = 0.0;
151: VecNorm(z[2],NORM_2,&norm);
152: v2 = norm-3.0*PetscSqrtReal((PetscReal)n); if (v2 > -PETSC_SMALL && v2 < PETSC_SMALL) v2 = 0.0;
153: PetscPrintf(PETSC_COMM_WORLD,"VecMAXPY %g %g %g \n",(double)v,(double)v1,(double)v2);
155: /*
156: Free work space. All PETSc objects should be destroyed when they
157: are no longer needed.
158: */
159: VecDestroy(&x);
160: VecDestroy(&y);
161: VecDestroy(&w);
162: VecDestroyVecs(3,&z);
163: PetscFinalize();
164: return ierr;
165: }
167: /*TEST
169: testset:
170: output_file: output/ex1_1.out
171: # This is a test where the exact numbers are critical
172: diff_args: -j
174: test:
176: test:
177: suffix: cuda
178: args: -vec_type cuda
179: requires: cuda
181: test:
182: suffix: kokkos
183: args: -vec_type kokkos
184: requires: kokkos_kernels
186: test:
187: suffix: hip
188: args: -vec_type hip
189: requires: hip
191: test:
192: suffix: 2
193: nsize: 2
195: test:
196: suffix: 2_cuda
197: nsize: 2
198: args: -vec_type cuda
199: requires: cuda
201: test:
202: suffix: 2_kokkos
203: nsize: 2
204: args: -vec_type kokkos
205: requires: kokkos_kernels
207: test:
208: suffix: 2_hip
209: nsize: 2
210: args: -vec_type hip
211: requires: hip
213: TEST*/