% Example 14.1a (Physics 330)

function s=leastsq(a,x,y)

%*********************************************************
% leastsq can be passed to fminsearch to do a
% non-linear least squares fit of the function
% funcfit(a,x) to the data set (x,y).
% funcfit.m is built by the user as described here

% a is a vector of variable parameters; x and y
% are the arrays of data points
%*********************************************************

% find s, the sum of the squares of the differences
% between the fitting function and the data

s=sum((y-funcfit(a,x)).^2);