finish gauss_seidel iteration
make it a function, deals with optional input arguments
annotation
convergence estimate
trivial change
partly initialized
finish matrixes except boundary condition
zeroflux BC
reset A cornet instead of phi boundary to zero
more matrixed need to be reset
zero flux means boundary flux is zero but not boundary mesh average flux is zero
now correct zeroflux
finish matrix construction
convergence rule from infinity norm to 2 norm
convergence estimate is based on S instead of A
finished in version of another k form
add iteration counter to my solution
divide source by keff and normalize flux to get compariable fraction change
reflective boundary test
debug A; normalize phi in my version