function [y]= sortbycol(x,a)

% SORTBYCOL
% This function sorts a matrix into accending order where only one
% column becomes sorted and the other entries just swap values in order 
% to maintain their relationship with the value in the sorted column. 
%
% Habtom Ressom
% February 22, 2005
% 
%  Y = SORTBYCOL(X,COLUMN)
% 
% Inputs are: X (matrix) and COLUMN
% Output: Y - sorted matrix


[b i] = sort(x(:,a),'ascend');
y = x(i,:);
end