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=head1 TITLE

Standardise Handling Of Abnormal Numbers Like Infinities And NaNs

=head1 VERSION

  Maintainer: Jarkko Hietaniemi <[EMAIL PROTECTED]>
  Date: 04 Aug 2000
  Version: 1
  Mailing List: [EMAIL PROTECTED]
  Number: 38

=head1 ABSTRACT

The handling of various abnormal numeric entities like infinities
(positive, negative), not-a-numbers (NaNs, various kinds of those,
signaling, non-signaling), epsilons (positive and negative) is left to
the native math libraries.  A more concerted effort to standardise the
behaviour of Perl across the platforms would be desirable.

=head1 DESCRIPTION

The abstract pretty much took care of it.

=head1 IMPLEMENTATION

In an SV have bits that mark whether the numeric aspect of the scalar
is abnormal and if so, what kind of abnormality are we dealing with.
The Perl math operations have to watch out for those bits and do The
Right Thing before the native math ops kick in, so that for example
infinity + anything-but-nan = infinity, anything + nan = nan, and so on.

Watching out for the abnormality bits may be a performance hit.  If
so, it may be possible during the configuration phase probe how well
the native math semantics obey the semantics we define for Perl, and
let the native math take care of where it and us agree.

=head1 REFERENCES

        Math::Complex

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