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[Python-Dev] histerical math.log(zero)

Samuele Pedroni pedronis at bluewin.ch
Mon Aug 4 19:45:17 EDT 2003 
At 12:31 04.08.2003 -0400, Tim Peters wrote:
>[Samuele Pedroni]
> > math.log raises different unrelated exceptions depending on the type
> > of a zero argument:
>
>It may, and probably does on most platforms.  Which exception gets raised
>for a float 0.0, and even whether an exception gets raised at all in that
>case, depends on what the platform libm does.  Standard C allows a lot of
>variation here.
>
> >  >>> math.log(0)
> >
> > Traceback (most recent call last):
> >    File "<pyshell#1>", line 1, in -toplevel-
> >      math.log(0)
> > OverflowError: math range error
> >  >>> math.log(0L)
>
>Python handles log(long) itself, so the exception in this case is
>platform-independent.

I was asking this because I have just finished making jython handle 
log(long) itself too.
And I noticed that test_long is picky about the ValueError thing.

I should have read the manual, sorry. I was more wondering that there's no 
encompassing math exception.

regards.
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