[PYTHON MATRIX-SIG] Compiling on HPUX with gcc

James Hugunin jjh@Goldilocks.LCS.MIT.EDU
Mon, 29 Jan 96 14:22:36 EST

   From: David Redish <David_Redish@GS151.SP.CS.CMU.EDU>

<SNIP> stuff about embarassing error covered elsewhere <SNIP>

   However, I get a ld error when I try to load it saying unsatisfied
   symbol: "finite".

   Am I missing a file?

You're not missing a file, you're running into one of the unfortunate
system dependent issues in IEEE libraries.  

On most systems, the standard library includes the function "finite"
which returns true iff a floating point value is not +-Inf, and not

This function is only referenced in ofuncobject.c in the macro CHECK
which is defined at the top of the file.

A quick fix is to just define CHECK(x) as nothing.  This will mean
that the umathmodule will not check for floating point overflows in
calculations as it should.

A better solution would be for you to figure out how to get this
desired behavior on HPUX and send me the patches.

A good check to see if you have a working implementation is to do the

>>> import umath
>>> umath.multiply(1.0e200, 1.0e200)
This should produce OverflowError

If instead it returns Infinity, you know that your routine is not
doing the needed checks.

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