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- Additional sanity checks added for debug=True in nonlinear_fit.
- nonlinear_fit now uses gvar.regulate rather than gvar.svd to
deal with singular correlation matrices and to decompose the
correlation matrices when forming the chi**2 function.
To regulate the correlation matrix, one now specifies
either eps or svdcut. The eps regulator uses Cholesky
decomposition, while the svdcut uses SVD decomposition
(the only option previously). Cholesky decomposition
is faster but less robust. Keywords add_svdnoise and
add_priornoise are replaced by addnoise, but the old
keywords continue to work (for legacy code).
- Tweak to reporting on stopping conditions.
- Updated documentation.
- Requires gvar v11.6 or later.