C 代码 应用有限元法 （FEM），使用分段线性单元， 矩形中的二维边界值问题 （BVP）.rar

19 January 2020 11:30:35 AM FEM2D_BVP_LINEAR_TEST C version Test the FEM2D_BVP_LINEAR library. TEST01 Solve - del ( A del U ) + C U = F on the unit square with zero boundary conditions. A1(X,Y) = 1.0 C1(X,Y) = 0.0 F1(X,Y) = 2*X*(1-X)+2*Y*(1-Y) U1(X,Y) = X * ( 1 - X ) * Y * ( 1 - Y ) Number of X grid values NX = 3 Number of Y grid values NY = 3 I J X Y U Uexact Error 0 0 0.000000 0.000000 0.000000 0.000000 0.000000e+00 1 0 0.500000 0.000000 0.000000 0.000000 0.000000e+00 2 0 1.000000 0.000000 0.000000 0.000000 0.000000e+00 0 1 0.000000 0.500000 0.000000 0.000000 0.000000e+00 1 1 0.500000 0.500000 0.078125 0.062500 1.562500e-02 2 1 1.000000 0.500000 0.000000 0.000000 0.000000e+00 0 2 0.000000 1.000000 0.000000 0.000000 0.000000e+00 1 2 0.500000 1.000000 0.000000 0.000000 0.000000e+00 2 2 1.000000 1.000000 0.000000 0.000000 0.000000e+00 l1 norm of error = 0.00173611 L2 norm of error = 0.00968806 Seminorm of error = 0.0771115 FEM2D_BVP_LINEAR_TEST Normal end of execution. 19 January 2020 11:30:35 AM