From: Sasha <nd...@ma...> - 2006-06-12 22:15:17
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I don't know about numarray, but the difference between Numeric and python math module stems from the fact that the math module ignores errno set by C library and only checks for infinity. Numeric relies on errno exclusively, numpy ignores errors by default: >>> import numpy,math,Numeric >>> numpy.exp(-760) 0.0 >>> math.exp(-760) 0.0 >>> Numeric.exp(-760) Traceback (most recent call last): File "<stdin>", line 1, in ? OverflowError: math range error >>> numpy.exp(760) inf >>> math.exp(760) Traceback (most recent call last): File "<stdin>", line 1, in ? OverflowError: math range error >>> Numeric.exp(760) Traceback (most recent call last): File "<stdin>", line 1, in ? OverflowError: math range error I would say it's a bug in Numeric, so you are out of luck. Unfortunalely, even MA.exp(-760) does not work, but this is easy to fix: >>> exp = MA.masked_unary_operation(Numeric.exp,0.0,MA.domain_check_interval(-100,100)) >>> exp(-760).filled() 0 You would need to replace -100,100 with the bounds appropriate for your system. On 6/12/06, Sebastian Haase <ha...@ms...> wrote: > Hi, > I'm using Konrad Hinsen's LeastSquares.leastSquaresFit for a convenient way to > do a non linear minimization. It uses the "old" Numeric module. > But since I upgraded to Numeric 24.2 I get OverflowErrors that I tracked down > to > >>> Numeric.exp(-760.) > Traceback (most recent call last): > File "<input>", line 1, in ? > OverflowError: math range error > > >From numarray I'm used to getting this: > >>> na.exp(-760) > 0.0 > > Mostly I'm confused because my code worked before I upgraded to version 24.2. > > Thanks for any hints on how I could revive my code... > -Sebastian Haase > > > _______________________________________________ > Numpy-discussion mailing list > Num...@li... > https://lists.sourceforge.net/lists/listinfo/numpy-discussion > |