五点差分格式.doc

#include<>#include<>#defineN30#(){ intn,m;doubleh; doublef[N][N][N];doublex[N],y[N]; inti,j,k; doublea,b,c,d; printf("请输入X,Y步长h:\n");scanf("%lf",&h); printf("请输入X的端点:\n");scanf("%lf%lf",&a,&b); n=(b-a)/h; printf("请输入Y的端点:\n");scanf("%lf%lf",&c,&d); m=(d-c)/h; for(i=0;i<=n;i++) { x[i]=a+i*h; } for(j=0;j<=m;j++) { y[j]=c+j*h; } for(i=0;i<=n;i++) { f[i][0][0]=sin(pi*x[i]/4); f[i][m][0]=; f[i][-1][0]=; }printf("\n"); for(j=0;j<=m;j++) { f[0][j][0]=y[j]*(3-y[j]); f[n][j][0]=; f[-1][j][0]=; } for(k=1;k<=3;k++) for(i=1;i<=n;i++) for(j=1;j<=m;j++) { f[i][j][k]=(f[i-1][j][k-1]+f[i-1][j-1][k-1]+f[i][j-1][k-1]+f[i][j][k-1])/4;printf("%lf\n",f[i][j][k]); }}/* for(j=0;j<n;j++) for(i=1;i<n;i++) {f[i][j+1]=r*f[i+1][j]+(1-2*r)*f[i][j]+r*f[i-1][j];}printf("\n空间节点为:\n");for(i=0;i<=10;