NumPy error

[Robert Kern]

jason wrote:
> Thanks.
> 
> After executing the first line, I now get:
> 
>>>>from scipy.optimize import fmin
> 
> Overwriting fft=<function fft at 0x012116F0> from scipy.fftpack.basic (was 
> <function fft at 0x011C8A70> from numpy.dft.fftpack)
> Overwriting ifft=<function ifft at 0x01211730> from scipy.fftpack.basic (was 
> <function inverse_fft at 0x011C8AB0> from numpy.dft.fftpack)
> 
> And then I get the following result:
> 
>>>>xopt = fmin(rosen, x0)
> 
> Optimization terminated successfully.
>          Current function value: 0.000066
>          Iterations: 141
>          Function evaluations: 243
> 
>>>>print xopt
> 
> [ 0.99910115  0.99820923  0.99646346  0.99297555  0.98600385]
> 
> Two questions:
> 1. does the "overwriting..." message make sense?

It's replacing the fft() and ifft() functions in numpy with the optimized
functions in scipy. I don't think we're doing that anymore in SVN scipy.

> I uninstalled scipy and numpy and re-installed them.
> 
> 2. has the algorithm (accuracy level) changed? the result seems different 
> from that reported in
> http://www.scipy.org/Wiki/Documentation?action=AttachFile&do=get&target=scipy_tutorial.pdf
> on page 12.

It is different. We're not really sure why. The simplex method is not an
algorithm known for its robustness.

Sorry about the confusion with dtypechar. Our releases of numpy and scipy got
out of sync.

-- 
Robert Kern
robert.kern at gmail.com

"In the fields of hell where the grass grows high
 Are the graves of dreams allowed to die."
  -- Richard Harter