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On Saturday, August 22, 2015 3:26:56 PM hw wrote: |
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> Hi, |
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> I have the following in a perl script: |
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> if ($a != $b) { |
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> print "e: '$a', t: '$b'\n"; |
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> } |
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> That will print: |
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> e: '69.99', t: '69.99' |
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> When I replace != with ne (if ($a ne $a) {), it doesn't print. |
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> Is that a bug or a feature? And if it's a feature, what's the explanation? |
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> And how do you deal with comparisions of variables when you get randomly |
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> either correct results or wrong ones? It's randomly because this |
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> statement checks multiple values in the script, and 69.99 is the only |
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> number showing up yet which isn't numerically equal to itself (but equal |
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> to itself when compared as strings). |
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Most languages have a decimal type that you should use when you need exact |
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math. I think for perl this is what you want: |
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http://search.cpan.org/~zefram/Math-Decimal-0.003/lib/Math/Decimal.pm |
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-- |
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Fernando Rodriguez |
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