[Nipy-devel] attributes error

[Jonathan Taylor]

I wanted to change a read-only attribute (the slice attribute of 
SliceIteratorNext) to
not read-only but "untyped". I changed "readonly" to "attribute" and got 
the following message:

--------------
Traceback (most recent call last):
  File "run.py", line 173, in ?
    FIACrun(subj=subj, run=run)
  File "run.py", line 134, in FIACrun
    OLS.fit()
  File 
"/home/jtaylo/python/lib/python2.4/site-packages/neuroimaging/fmri/fmristat/__init__.py", 
line 107, in fit
    LinearModelIterator.fit(self, **keywords)
  File 
"/home/jtaylo/python/lib/python2.4/site-packages/neuroimaging/statistics/regression.py", 
line 48, in fit
    output.next(data=out)
  File 
"/home/jtaylo/python/lib/python2.4/site-packages/neuroimaging/fmri/regression.py", 
line 40, in next
    value.slice = value.slice[1]
  File "/home/jtaylo/python/lib/python2.4/site-packages/attributes.py", 
line 256, in set
    self.validate(value)
  File "/home/jtaylo/python/lib/python2.4/site-packages/attributes.py", 
line 211, in validate
    if not self.isvalid(value): raise ProtocolOmission(
protocols.ProtocolOmission: attribute slice implements ([slice(0, 191, 
1), slice(0, 1, 1)],), value slice(0, 1, 1) of type <type 'slice'> does 
not implement: ('__getslice__', 'pop', 'remove', '__rmul__', '__lt__', 
'append', 'index', '__delslice__', '__getitem__', '__contains__', 
'__len__', 'sort', '__ne__', 'extend', 'insert', '__iter__', '__add__', 
'__gt__', '__eq__', 'reverse', 'count', '__delitem__', '__reversed__', 
'__imul__', '__setslice__', '__setitem__', '__iadd__', '__le__', 
'__mul__', '__ge__')

---------------------------

I am not sure how to get this to work. I want it to behave like a slice or a list of slices.

There is a very good example when you want to be able to change its value later: when the "iterator" driving the voxelwise analysis comes from an fMRI image, it spits out
slices of time series, but if you want to output slices of floats (i.e. a 3d image of means), you want to ignore the first part of this (python) slice but you can still use the same "SliceIteratorNext" instance to drive the next method of the images....

Thanks,

Jonathan

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Jonathan Taylor                           Tel:   650.723.9230
Dept. of Statistics                       Fax:   650.725.8977
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