xref: /petsc/src/ts/tutorials/phasefield/potentials.c (revision f97672e55eacc8688507b9471cd7ec2664d7f203)
1 
2 static char help[] = "Plots the various potentials used in the examples.\n";
3 
4 #include <petscdmda.h>
5 #include <petscts.h>
6 #include <petscdraw.h>
7 
8 int main(int argc,char **argv)
9 {
10   PetscDrawLG               lg;
11   PetscInt                  Mx = 100,i;
12   PetscReal                 x,hx = .1/Mx,pause,xx[3],yy[3];
13   PetscDraw                 draw;
14   const char *const         legend[] = {"(1 - u^2)^2","1 - u^2","-(1 - u)log(1 - u)"};
15   PetscDrawAxis             axis;
16   PetscDrawViewPorts        *ports;
17 
18   PetscFunctionBegin;
19   PetscCall(PetscInitialize(&argc,&argv,0,help));
20   PetscCall(PetscViewerDrawResize(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),1200,800));
21   PetscCall(PetscViewerDrawGetDrawLG(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),0,&lg));
22   PetscCall(PetscDrawLGGetDraw(lg,&draw));
23   PetscCall(PetscDrawCheckResizedWindow(draw));
24   PetscCall(PetscDrawViewPortsCreateRect(draw,1,2,&ports));
25   PetscCall(PetscDrawLGGetAxis(lg,&axis));
26   PetscCall(PetscDrawLGReset(lg));
27 
28   /*
29       Plot the  energies
30   */
31   PetscCall(PetscDrawLGSetDimension(lg,3));
32   PetscCall(PetscDrawViewPortsSet(ports,1));
33   x    = .9;
34   for (i=0; i<Mx; i++) {
35     xx[0] = xx[1] = xx[2] = x;
36     yy[0] = (1.-x*x)*(1. - x*x);
37     yy[1] = (1. - x*x);
38     yy[2] = -(1.-x)*PetscLogReal(1.-x);
39     PetscCall(PetscDrawLGAddPoint(lg,xx,yy));
40     x    += hx;
41   }
42   PetscCall(PetscDrawGetPause(draw,&pause));
43   PetscCall(PetscDrawSetPause(draw,0.0));
44   PetscCall(PetscDrawAxisSetLabels(axis,"Energy","",""));
45   PetscCall(PetscDrawLGSetLegend(lg,legend));
46   PetscCall(PetscDrawLGDraw(lg));
47 
48   /*
49       Plot the  forces
50   */
51   PetscCall(PetscDrawViewPortsSet(ports,0));
52   PetscCall(PetscDrawLGReset(lg));
53   x    = .9;
54   for (i=0; i<Mx; i++) {
55     xx[0] = xx[1] = xx[2] = x;
56     yy[0] = x*x*x - x;
57     yy[1] = -x;
58     yy[2] = 1.0 + PetscLogReal(1. - x);
59     PetscCall(PetscDrawLGAddPoint(lg,xx,yy));
60     x    += hx;
61   }
62   PetscCall(PetscDrawAxisSetLabels(axis,"Derivative","",""));
63   PetscCall(PetscDrawLGSetLegend(lg,NULL));
64   PetscCall(PetscDrawLGDraw(lg));
65 
66   PetscCall(PetscDrawSetPause(draw,pause));
67   PetscCall(PetscDrawPause(draw));
68   PetscCall(PetscDrawViewPortsDestroy(ports));
69   PetscCall(PetscFinalize());
70   return 0;
71 }
72 
73 /*TEST
74 
75    test:
76      requires: x
77 
78 TEST*/
79