matrix.m

matlab教程和源程序

clc;clear all;
J=200;
dimJ=J+1;
n = (dimJ)^2;
L=sparse(n,n);
L(1,1)=3; L(1,2)=-3/2; L(J+1,J+1)=6; L(J+1,J)=-3;
L=L+sparse(2:J,3:J+1,-1,n,n);
L=L+sparse(2:J,2:J,4,n,n);
L=L+sparse(2:J,1:J-1,-1,n,n);
L(1,J+2)=-3/2; L(J+1,2*J+2)=-3;
L=L+sparse(2:J,J+3:2*J+1,-2,n,n);
L(n-J,n-J)=6; L(n-J,n-J+1)=-3; 
L(n,n)=3; L(n,n-1)=-3/2;
L=L+sparse(n-J+1:n-1,n-J+2:n,-1,n,n);
L=L+sparse(n-J+1:n-1,n-J+1:n-1,4,n,n);
L=L+sparse(n-J+1:n-1,n-J:n-2,-1,n,n);
L(n-J,n-(2*J+1))=-3; L(n,n-dimJ)=-3/2;
L=L+sparse(n-J+1:n-1,n-2*J:n-(J+2),-2,n,n);
L=L+sparse(J+2:n-dimJ,2*J+3:n,-1,n,n);
L=L+sparse(J+2:n-dimJ,1:n-2*dimJ,-1,n,n);
L=L+sparse(J+2:n-dimJ,J+2:n-dimJ,4,n,n);
L=L+sparse(J+2:n-(J+2),J+3:n-dimJ,-1,n,n);
L=L+sparse(J+2:dimJ:n-(2*J+1),J+3:dimJ:n-2*J,-1,n,n); 
L=L+sparse(2*J+2:dimJ:n-2*dimJ,2*J+3:dimJ:n-(2*J+1),1,n,n);
L=L+sparse(J+3:n-dimJ,J+2:n-(J+2),-1,n,n);
L=L+sparse(2*J+2:dimJ:n-dimJ,2*J+1:dimJ:n-(J+2),-1,n,n);
L=L+sparse(2*J+3:dimJ:n-(2*J+1),2*J+2:dimJ:n-2*dimJ,1,n,n);