Problem of polyfit

[Tetsuro KURITA]

The following code in "polyfit.m" never give the best fit data in the 
least squares sense as described in document.

  X = (x * ones (1, n+1)) .^ (ones (l, 1) * (n : -1 : 0));
  p = X \ y;

This code do nothing to mimimize `sumsq (p(x(i)) - y(i))'.

I think this code should be modified as follows.

X = (x * ones (1, n+1)) .^ (ones (l, 1) * (n: -1 : 0))
W = X'*X
z = X'*y
p = inv(W)*z

I am using Octave 2.1.57 on MacOS X.

=======================================================
 Tetsuro KURITA
  E-mail: address@hidden
  http://homepage.mac.com/tkurita/scriptfactory/
=======================================================



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