As Nick pointed out, lapack library has the svd implementation used by
Matlab which seems more robust.
If you have lapack library and ctypes installed, you can use
hyper = Hyperalignment(ProcrusteanMapper(svd='dgesvd',space='commonspace'))

I have only tested this on linux, so please let me know if you run
into any issues.

Best,
Swaroop

On Wed, Apr 2, 2014 at 8:55 AM, Nick Oosterhof
<[email protected]> wrote:
>
> On Apr 2, 2014, at 5:44 PM, andrea bertana <[email protected]> wrote:
>
>> I'm trying to use Hyperalignment() procedure to align different subjects' 
>> brain.
>> I am mainly referring to the example described in this webpage - 
>> http://dev.pymvpa.org/examples/hyperalignment.html
>> However, when I try to compute the common space on the training set (10 
>> participant, single - participant matrix: 301 time-point x 1000 voxels ) I 
>> get the following message:
>>
>> LinAlgError, 'SVD did not converge'
>
> Yes, I've had that issue too, and we've had some discussion in the lab. It 
> turns out the blas library provides better SVD support than numpy itself. The 
> issue is reported here
>
> https://github.com/numpy/numpy/issues/1588
>
> and seems still open.
>
> For me this problem occurred using mac os, where numpy did not use other 
> libraries . At some point I tried to use the blas libraries but failed 
> miserably.
> On the positive side, using neurodebian in a virtualbox worked for me.
>
> On what platform are you working? If not neurodebian you might consider 
> trying it (either installed, or through virtualbox).
>
> (in a perfect world the blas or other SVD-supporting libraries would be made 
> to work on any platform, but I don't know how hard that is)
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