[Numpy-discussion] subtract.reduce behavior

Johann Hibschman jhibschman+numpy@gmail....
Thu Jul 22 15:00:50 CDT 2010


I'm trying to understand numpy.subtract.reduce.  The documentation
doesn't seem to match the behavior.  The documentation claims

  For a one-dimensional array, reduce produces results equivalent to:

  r = op.identity
  for i in xrange(len(A)):
     r = op(r,A[i])
  return r

However, numpy.subtract.reduce([1,2,3]) gives me 1-2-3==-4, not
0-1-2-3==-6.

Now, I'm on an older version (1.3.0), which might be the problem, but
which is "correct" here, the code or the docs?

Thanks,
Johann



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