Someone has decided to change nnz and to remove the nonzeros command.
I find this very unacceptable!
It is a bad practice to not allow for backward compatibility.
Many of our codes use these command…
_Original ticket http://projects.scipy.org/scipy/ticket/1248 on 2010-07-26 by trac user johngabriel, assigned to unknown._
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#Error in scipy.optimize.rosen_hess, in H[0,0] position, when x[0] != 1…