xref: /petsc/src/ts/tutorials/phasefield/potentials.c (revision ee12ae39415b2e672d944cdca066227dadbf8b14)
1 
2 static char help[] = "Plots the various potentials used in the examples.\n";
3 
4 
5 #include <petscdmda.h>
6 #include <petscts.h>
7 #include <petscdraw.h>
8 
9 
10 int main(int argc,char **argv)
11 {
12   PetscDrawLG               lg;
13   PetscErrorCode            ierr;
14   PetscInt                  Mx = 100,i;
15   PetscReal                 x,hx = .1/Mx,pause,xx[3],yy[3];
16   PetscDraw                 draw;
17   const char *const         legend[] = {"(1 - u^2)^2","1 - u^2","-(1 - u)log(1 - u)"};
18   PetscDrawAxis             axis;
19   PetscDrawViewPorts        *ports;
20 
21 
22   PetscFunctionBegin;
23   ierr = PetscInitialize(&argc,&argv,0,help);if (ierr) return ierr;
24   ierr = PetscViewerDrawResize(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),1200,800);CHKERRQ(ierr);
25   ierr = PetscViewerDrawGetDrawLG(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),0,&lg);CHKERRQ(ierr);
26   ierr = PetscDrawLGGetDraw(lg,&draw);CHKERRQ(ierr);
27   ierr = PetscDrawCheckResizedWindow(draw);CHKERRQ(ierr);
28   ierr = PetscDrawViewPortsCreateRect(draw,1,2,&ports);CHKERRQ(ierr);
29   ierr = PetscDrawLGGetAxis(lg,&axis);CHKERRQ(ierr);
30   ierr = PetscDrawLGReset(lg);CHKERRQ(ierr);
31 
32   /*
33       Plot the  energies
34   */
35   ierr = PetscDrawLGSetDimension(lg,3);CHKERRQ(ierr);
36   ierr = PetscDrawViewPortsSet(ports,1);CHKERRQ(ierr);
37   x    = .9;
38   for (i=0; i<Mx; i++) {
39     xx[0] = xx[1] = xx[2] = x;
40     yy[0] = (1.-x*x)*(1. - x*x);
41     yy[1] = (1. - x*x);
42     yy[2] = -(1.-x)*PetscLogReal(1.-x);
43     ierr  = PetscDrawLGAddPoint(lg,xx,yy);CHKERRQ(ierr);
44     x    += hx;
45   }
46   ierr = PetscDrawGetPause(draw,&pause);CHKERRQ(ierr);
47   ierr = PetscDrawSetPause(draw,0.0);CHKERRQ(ierr);
48   ierr = PetscDrawAxisSetLabels(axis,"Energy","","");CHKERRQ(ierr);
49   ierr = PetscDrawLGSetLegend(lg,legend);CHKERRQ(ierr);
50   ierr = PetscDrawLGDraw(lg);CHKERRQ(ierr);
51 
52   /*
53       Plot the  forces
54   */
55   ierr = PetscDrawViewPortsSet(ports,0);CHKERRQ(ierr);
56   ierr = PetscDrawLGReset(lg);CHKERRQ(ierr);
57   x    = .9;
58   for (i=0; i<Mx; i++) {
59     xx[0] = xx[1] = xx[2] = x;
60     yy[0] = x*x*x - x;
61     yy[1] = -x;
62     yy[2] = 1.0 + PetscLogReal(1. - x);
63     ierr  = PetscDrawLGAddPoint(lg,xx,yy);CHKERRQ(ierr);
64     x    += hx;
65   }
66   ierr = PetscDrawAxisSetLabels(axis,"Derivative","","");CHKERRQ(ierr);
67   ierr = PetscDrawLGSetLegend(lg,NULL);CHKERRQ(ierr);
68   ierr = PetscDrawLGDraw(lg);CHKERRQ(ierr);
69 
70   ierr = PetscDrawSetPause(draw,pause);CHKERRQ(ierr);
71   ierr = PetscDrawPause(draw);CHKERRQ(ierr);
72   ierr = PetscDrawViewPortsDestroy(ports);CHKERRQ(ierr);
73   ierr = PetscFinalize();
74   return ierr;
75 }
76 
77 /*TEST
78 
79    test:
80      requires: x
81 
82 TEST*/
83