Hi, I think I have found a bug in the function "apply_along_axis". recall that the function definition if apply_along_axis(func1d, axis, arr, *args) This bug occurs if func1d returns a python object without a __len__ attribute and is not a scalar, determined by numpy.core.numeric.isscalar. eg. a self contained example of the bug is:

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from numpy import array, apply_along_axis

# works arr = array( [1,1] ) apply_along_axis( lambda arr:arr[0], 0, arr )

# however this raises a type error class Foo(object): pass

arr = array( [ Foo(), Foo() ] ) apply_along_axis( lambda arr:arr[0], 0, arr )

--- exceptions.TypeError Traceback (most recent call last) /sw/lib/python2.4/site-packages/numpy/lib/shape_base.py in apply_along_axis(func1d, axis, arr, *args) 52 holdshape = outshape 53 outshape = list(arr.shape) ---> 54 outshape[axis] = len(res) 55 outarr = zeros(outshape,asarray(res).dtype) 56 outarr[tuple(i.tolist())] = res TypeError: len() of unsized object

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Thanks ~Sean