Confusing problem (well, for me anyway)

[Duncan Smith]

I cannot see what I am doing wrong here.  The following function won't make
a great deal of sense on its own, but I'm hoping my error is obvious enough
that that won't matter.  The output below the function highlights the
problem.

    def __cmp__(self, other):
        indices = []
        for variable in other.variables:
            indices.append(self.variables.index(variable))
        try:
            self.transpose(indices)
        except:
            return 0
        if self.variables == other.variables:
            array1, array2 = self.values, other.values
            ##########################################
            comp = array1 == array2
            for i in range(len(array1.shape)):
                comp = Numeric.add.reduce(comp)
            size = Numeric.multiply.reduce(array1.shape)
            print comp, size, comp == size
            if comp == size:
                print 'returning 1'
                return 1
            else:
                print 'returning 0'
                return 0
            ###########################################
        else:
            return 0


>>> reload(disc)
<module 'disc' from 'C:\Python22\disc.pyc'>
>>> t = disc.RandomTable(0, 6, [2,3])
>>> t1 = t.copy()
>>> t
array([[4, 4, 3],
       [2, 3, 4]]) ['var1', 'var2']
>>> t1
array([[4, 4, 3],
       [2, 3, 4]]) ['var1', 'var2']
>>> t == t1
6 6 1
returning 1
0
>>> t.values[(0,0)] = 5
>>> t == t1
5 6 0
returning 0
1
>>> t.values[(0,0)] = 4
>>> t == t1
6 6 1
returning 1
0
>>>


I cannot see why the function returns 1 when it should return 0 (and
vice-versa).  How can it print 'returning 1' and then return 0?  If I place
the code between the lines of hashes in a separate function and pass it two
Numeric arrays as arguments I get the behaviour I'd expect.

def equals(array1, array2):
    comp = array1 == array2
    for i in range(len(array1.shape)):
        comp = Numeric.add.reduce(comp)
    size = Numeric.multiply.reduce(array1.shape)
    if comp == size:
        print 'returning 1'
        return 1
    else:
        print 'returning 0'
        return 0


>>> disc.equals(array1, array2)
returning 1
1

But if I replace the section of code with 'return equals(array1, array2)',
then I'm back to the 'strange' behaviour.  Any ideas?  Cheers.

Duncan