Hello Masayoshi Fujimoto, and welcome to the Monastery!

The function rad2rad is not exported by the Math::Trig module, so to use it you need to put the full module name in front:

my $radians_wrapped_by_2pi = Math::Trig::rad2rad($radians);

[download]

Update: Here is an example of rad2rad() in use:

use Modern::Perl;
use Math::Trig ':pi';

my $radians = 4.5 * pi;
my $radians_wrapped_by_2pi = Math::Trig::rad2rad($radians);

say 'rad2rad(', $radians, ') = ', $radians_wrapped_by_2pi;

[download]

Output:

 1:49 >perl 502_SoPW.pl
rad2rad(14.1371669411541) = 1.5707963267949

 1:49 >

[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: How to use rad2rad by Athanasius
in thread How to use rad2rad by Masayoshi Fujimoto

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