[SciPy-user] Schur complement

[Pearu Peterson]

On Wed, 26 May 2004, Nils Wagner wrote:

> > In short, use
> > 
> > def func(x):
> >    return abs(schur(T(x[0])))
                           ^^^

> > 
> I have modified my program.
> 
> def func2(x):
>   return abs(schur(T(x)))
> 
> r6 = optimize.fsolve(func2,x0)
> 
> Now I get
> 
> Traceback (most recent call last):
> ValueError: array too large for destination

Compare my suggestion with your version of func2 (notice ^^^).

> The requirement, i.e. func is real is not mentioned in help 
> (optimize.fsolve). Am I missing something ?

Notice that it also does not mention that func can be complex valued.
Anyways, fsolve assumes real-valued functions - `.`. But it is also simple 
to use fsolve for complex-valued functions: make sure that func returns real 
and imaginary parts of a function value, also an initial value to 
fsolve should be specified as a pair of real and imaginary parts of the 
value.

Pearu