% find zero crossings from the determinant search

function [char_root] = find_root(x,y);
%input:
%   x = beta*L value;
%   y = magnitude of determinant
%
% output:
%   char_roots = beta*L that correspond to det|Char. matrix| = 0
%
char_root=zeros(1,0); 
n = max(size(y));
for i =2: (n-1)
    if ( y(i)>0.0) 
        if (y(i+1)<0.) 
             char_root =[char_root x(i)];
        end;
    end;
    if ( y(i)<0.0) 
        if (y(i+1)>0.) 
             char_root =[char_root x(i+1)];
        end;
    end;
end;
return;