[pymvpa] searchlight gets stuck, issues error

[Sergey.V.Fogelson at Dartmouth.edu]

Hello,

Im running the searchlight algorithm on some data and it gets stuck  
right around 68% complete.

Ive zscored and detrended the dataset before preprocessing. the error  
that is issued says that the SVM classifier cannot converge because of  
zero norm.

here's the code ive used to preprocess the data:

if __debug__:
     debug.active += ["SLC"]

attr = SampleAttributes('FFA_class_25jan10sf0')

dataset = NiftiDataset(samples='25jan10sf.nii', labels=attr.labels,  
chunks=attr.chunks, mask = 'mask.nii')

detrend(dataset, perchunk=True, model="linear", polyord = 1)

zscore(dataset, perchunk=True,targetdtype= 'float16')

dataset = dataset.select( labels = [1,2] )

clf = LinearCSVMC()

cv = CrossValidatedTransferError(TransferError(clf), NFoldSplitter())
s1 = Searchlight(cv, radius=9)


s1_map = s1(dataset)
orig_s1_map = dataset.mapReverse(N.array(s1_map))
data_hdr = dataset.niftihdr
NiftiImage(orig_s1_map,header=data_hdr).save('9mmSL_SVM_tr1_facevshouse.nii.gz')



thanks very much for your help,
Sergey.