Along those lines, I'd suggest streamlining it even more and submitting it as a test file (i.e. use Test::More instead of print. For example: 

use strict;
use warnings;
use Test::More tests => 3;
use bignum;

sub xe{
 $_[0]*log($_[0])+log(atan2(1,1)*8*$_[0])/2
  + 1/(12*$_[0]) - 1/(360*($_[0]**3)) + 1/(1260*($_[0]**5));
}

my ($m, $n, $r) = ( 2**96, 3*(10**6), 1*(10**6) );

my $e=exp(xe($m-$n)+xe($m-$r)-xe($m)-xe($m-$n-$r));

is( $e      , 1,    '$e should equal 1'     );
is( 1-$e    , 0,    '1-$e should equal 0'   );
is( 1-"$e"  , 0,    '1-"$e" should equal 0' );

[download]

Gives:

1..3
ok 1 - $e should equal 1
not ok 2 - 1-$e should equal 0
#     Failed test (bigtest.pl at line 17)
#          got: '1'
#     expected: '0'
ok 3 - 1-"$e" should equal 0
# Looks like you failed 1 test of 3.

[download]

That's even easier for a module author to work with.

-xdg

Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

In reply to Re^3: Help me make a test case for Math::BigFloat by xdg
in thread Help me make a test case for Math::BigFloat by fizbin

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