[EMAIL PROTECTED] wrote: > >On Wed, 11 Oct 2006, Travis Oliphant wrote: > > > >>On the other hand requiring all calls to numpy.sqrt to go through an >>"argument-checking" wrapper is a bad idea as it will slow down other uses. >> >> > >Interestingly, in worst cases numpy.sqrt is approximately ~3 times slower >than scipy.sqrt on negative input but ~2 times faster on positive input: > >In [47]: pos_input = numpy.arange(1,100,0.001) > >In [48]: %timeit -n 1000 b=numpy.sqrt(pos_input) >1000 loops, best of 3: 4.68 ms per loop > >In [49]: %timeit -n 1000 b=scipy.sqrt(pos_input) >1000 loops, best of 3: 10 ms per loop > >
This is the one that concerns me. Slowing everybody down who knows they have positive values just for people that don't seems problematic. >In [50]: neg_input = -pos_input > >In [52]: %timeit -n 1000 b=numpy.sqrt(neg_input) >1000 loops, best of 3: 99.3 ms per loop > >In [53]: %timeit -n 1000 b=scipy.sqrt(neg_input) >1000 loops, best of 3: 29.2 ms per loop > >nan's are making things really slow, > > Yeah, they do. This actually makes the case for masked arrays, rather than using NAN's. -Travis ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Numpy-discussion mailing list Numpy-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/numpy-discussion
