中文说明：有限体积法椭圆1D MATLAB与Dirichlet 和Neumann边界条件解方程-u_xx= F与Dirichlet 和Neumann边界条件
English Description：
Finite Volume Method Elliptic 1D MATLAB with Dirichlet and Neumann boundary conditionSolve equation -u_xx=f with Dirichlet and Neumann boundary condition