[Numpy-discussion] RE: Possible bug (was Re: numpy, overflow, inf, ieee, and rich comparison)

Paul F. Dubois pauldubois at home.com
Thu Oct 12 02:04:51 CEST 2000


I don't have time to follow in detail this thread about changed behavior
between versions. These observations are based on working with hundreds of
code authors. I offer them as is.

a. Nobody runs a serious numeric calculation without setting
underflow-to-zero, in the hardware. You can't even afford the cost of
software checks. Unfortunately there is no portable way to do that that I
know of.

b. Some people use Inf but most people want the code to STOP so they can
find out where the INFS started. Otherwise, two hours later you have big
arrays of Infs and no idea how it happened. Likewise sqrt(-1.) needs to
stop, not put a zero and keep going.










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