src.m

五点差分型多重网格方法：各种插值算子的比较）

%======design right function of FEM  =================================
%========  It is adapted for get_matrix_fem.m =========================
function z=SRC(x,y)
 %z= 2*((1-6*x.*x).*y.*y.*(1-y.*y)+(1-6*y.*y).*x.*x.*(1-x.*x)); 
  
 z= (2*pi*pi+1)*cos(pi*x).*cos(pi*y);
 % z= 2*pi*pi*cos(pi*x).*cos(pi*y);