MATLAB Code to solve the convection equation

This is a MATLAB code that solves the 2D convection equation using Finite Volume Method. Interpolation scheme used is a combination of Central Differencing and Upwind Interpolation and hence is called "Deferred Correction" scheme that uses a blending factor beta. Setting beta =1 uses the second order accurate central differencing while setting beta=0 uses first order accurate upwind differencing. Boundary conditions involve both Dirchlet and Neumann boundary conditions with the scalar field phi set to 1 along the north and 0 along the west, while the east and south boundaries are characterized by setting d(phi)/dx to zero on the west face and d(phi)/dy to zero on the south face. Different plots for the equations can be obtained by tweaking the blending factor.