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How do I create/detect/handle Infinity?

( #783071=categorized question: print w/ replies, xml ) Need Help??
Contributed by jdporter on Jul 24, 2009 at 18:11 UTC
Q&A  > math


Description:

N/T

Answer: How do I create/detect/handle Infinity?
contributed by shmem

Creating Inf/NaN:

use Devel::Peek; $inf = (~@~)**(~@~); $nan = $inf / $inf; Dump $_ for $inf, $nan; __END__ SV = NV(0x9e15f84) at 0x9dfc11c REFCNT = 2 FLAGS = (NOK,pNOK) NV = inf SV = NV(0x9e15f9c) at 0x9dfc59c REFCNT = 2 FLAGS = (NOK,pNOK) NV = nan

Detecting Inf/NaN: since they are numeric values, Inf and NaN can be tested for with the numeric equality/inequality operators == and !=. For Inf, greater and less also work.

Handling: not useful ;-)

Devel::Peek

Answer: How do I create/detect/handle Infinity?
contributed by moritz

I think in Perl 5 this is platform specific, so I'll rather give the Perl 6 answer:

my $num = Inf; given $num { say "+Inf" when Inf; say "-Inf" when -Inf; say "NaN" when NaN; }

Works in Rakudo today.

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