need isnan and isinf src for microsoft c

[Richard Tobin]

In article <1991Apr22.173940.25021 at solo.csci.unt.edu> gene at ponder.csci.unt.edu (Gene De Lisa) writes:
>Could someone tell me how to detect NaN and infinite numbers

Infinities have the exponent set to its maximum value and the mantissa
zero.  NaNs have the same exponent but a non-zero mantissa.

For single precision the format is sign bit, 8 bit exponent, 23 bit mantissa.
For double precision the numbers are 11 and 52.

>in microsoft c?

Assuming it uses IEEE format, as above, but you have to be careful
about byte order.

-- Richard
-- 
Richard Tobin,                       JANET: R.Tobin at uk.ac.ed             
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