isnan(), fpclassify()

[BZ]

Hi!

I was wondering if the functionality of the C99 function isnan(),
isinf() and fp_classify() are available in perl.

Or even better, is it possible to get printf to recognise things like
'nan' and 'inf' as floats? They seems to be interpreted as text by
default:

[bas@matilda]~> perl -e 'printf "%e %e %e %e\n", "123", "nan", "inf", "-inf";'
1.230000e+02 0.000000e+00 0.000000e+00 -0.000000e+00

 

[Paul Lalli]

I was wondering if the functionality of the C99 function isnan(),
isinf() and fp_classify() are available in perl.

Or even better, is it possible to get printf to recognise things like
'nan' and 'inf' as floats?

Have a look at the Math::BigFloat module
(http://search.cpan.org/~tels/Math-BigInt-1.77/lib/Math/BigFloat.pm)
and see if that suits your needs.

They seems to be interpreted as text by
default:

[bas@matilda]~> perl -e 'printf "%e %e %e %e\n", "123", "nan", "inf", "-inf";'
1.230000e+02 0.000000e+00 0.000000e+00 -0.000000e+00

Correct. Any string that does not "look" like a number is treated as
the number 0 in numeric context.

Paul Lalli