solve_tridiag.m

function [x]=solve_tridiag(ud,uo,lo,b)
%Takes the main diagnol of the upper matrix and the off
%diagnol of the lower and upper matrices and the vector b.
%This function solves for the vector x.
y=zeros(1,length(ud));
for i = 1:(length(ud)-1)
y(1)=b(1);
y(i+1)= b(i+1)-(lo(i)*y(i));

end
x=zeros(1,length(ud));
for k =(length(ud):-1:2)
    
x(length(ud))=y(length(ud))/ud(length(ud));
x(k-1)= (y(k-1)-(uo(k-1)*x(k)))/(ud(k-1));

end