lu_tridiag.m

function [ud,uo,lo]=lu_tridiag(e,f,g);```
  % lu_tridiag calculates the components for LU-decomposition of a tridiagonal matrix
  % given its off-diagonal vectors, e and g 
  % and diagonal vector f
  % the output is 
  % the diagonal of the Upper matrix, ud
  % the off-diagonal of the Upper matrix, uo
  % and the off-diagonal of the Lower matrix, lo
  % note: the diagonal of the Lower matrix is all ones

end