scipy/scipy — pull request #446 by taldcroft (2013-02-22 22:26:10+00:00)
Title: Update the parameter documentation in curve_fit

The documentation describing the `sigma` parameter of the
`optimize.curve_fit` function was updated to remove the reference
to representing the standard deviation of the data. This is
misleading because the `sigma` value is used purely as a relative
weighting factor.

See also:
http://mail.scipy.org/pipermail/scipy-user/2013-February/034191.html