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in reply to Re: Not a Number
in thread Not a Number

NaN is an IEEE standard constant which stands for Not a Number. It is returned if an invalid operation exception occurs within an operation.

For example, sqrt(-1) will return a number with a bit configuration that is recognized as NaN because this operation would result in an imaginary number.

Therefore regexps don't help us in that issue.

-- yuriy

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Re: Re: Re: Not a Number
by physgreg (Scribe) on Oct 18, 2002 at 13:42 UTC
    When I tried the sqrt(-1) example, I got the message
    Can't take sqrt of -1 at -e line 1.
    so it would seem that NaN is not used.