/ 
Math-Float128-0.01
River stage zero No dependents
/ Math::Float128

NAME

Math::Float128 - perl interface to C's __float128 operations

BUGS

exp() segfaults with Strawberry Perl's 32-bit and 64-bit MinGW compilers.
Needs quadmath.h.

DESCRIPTION

use Math::Float128 qw(:all);

my $arg = 32.1;
my $f1 = Math::Float128->new($arg);# Stringify $arg, then assign 
                                       # using C's strtoflt128()
my $f2 = NVtoF128($arg); # Assign the NV 32.1 to $f2.

OVERLOADING

The following operations are overloaded:
 + - * / **
 += -= *= /= **=
 != == <= >= <=> < >
 ++ --
 =
 abs bool ! int print
 sqrt log exp
 sin cos atan2

 Arguments to the overloaded operations must be Math::Float128
 objects.

  $f = $f + 3.1; # currently an error. Do instead:

  $f = $f + Math::Float128->new('3.1');

ASSIGNMENT FUNCTIONS

The following create and assign a new Math::Float128.

 $f = Math::Float128->new($arg);
  Returns a Math::Float128 object to which the numeric value of $arg
  has been assigned.
  If no arg is supplied then $f will be NaN.

 $f = UVtoF128($arg);
  Returns a Math::Float128 object to which the numeric (unsigned
  integer) value of $arg has been assigned.

 $f = IVtoF128($arg);
  Returns a Math::Float128 object to which the numeric (signed
  integer) value of $arg has been assigned.

 $f = NVtoF128($arg);
  Returns a Math::Float128 object to which the numeric (floating
  point) value of $arg has been assigned.

 $f2 = F128toF128($f1);
  Returns a Math::Float128 object that is a copy of the
  Math::Float128 object provided as the argument.
  Courtesy of overloading, this is in effect no different to doing:
  $f2 = $f1;

 $f = STRtoF128($str);
  Returns a Math::Float128 object that has the value of the string
  $str.

ASSIGNMENT OF INF, NAN, UNITY and ZERO

$f = InfF128($sign);
 If $sign < 0, returns a Math::Float128 object set to
 negative infinity; else returns a Math::Float128 object set
 to positive infinity.

$f = NaNF128($sign);
 If $sign < 0, returns a Math::Float128 object set to
 negative NaN; else returns a Math::Float128 object set to
 positive NaN. It may be problematical as to whether a NaN
 with the correct sign has been returned ... but, either way,
 it should return a NaN.

$f = ZeroF128($sign);
 If $sign < 0, returns a Math::Float128 object set to
 negative zero; else returns a Math::Float128 object set to 
 zero.

$f = UnityF128($sign);
 If $sign < 0, returns a Math::Float128 object set to
 negative one; else returns a Math::Float128 object set to 
 one.

flt128_set_prec($precision);
 Sets the precision of stringified values to $precision decimal
 digits.

$precision = flt128_get_prec();
 Returns the precision (in decimal digits) that will be used
 when stringifying values (by printing them, or calling
 F128toSTR).

RETRIEVAL FUNCTIONS

The following functions provide ways of seeing the value of
Math::Float128 objects.

$nv = F128toNV($f);
 This function returns the value of the Math::Float128 object to
 a perl scalar (NV). It may not translate the value accurately.

$string = F128toSTR($f);
 Returns the value of the Math::Float128 object as a string.
 The returned string will contain the same as is displayed by
 "print $f", except that print() will strip the trailing zeroes
 in the mantissa (significand) whereas F128toSTR won't.
 By default, provides 33 decimal digits of precision. This can be
 altered by specifying the desired precision (in decimal digits)
 in a call to flt128_set_prec.

$string = F128toSTRP(f, $precision);
 Same as F128toSTR, but takes an additional arg that specifies the
 precision (in decimal digits) of the stringified return value.

OTHER FUNCTIONS

$bool = is_NaNF128($f); 
 Returns 1 if $f is a Math::Float128 NaN.
 Else returns 0

$int = is_InfF128($f)
 If the Math::Float128 object $f is -inf, returns -1.
 If it is +inf, returns 1.
 Otherwise returns 0.

$int = is_ZeroF128($f);
 If the Math::Float128 object $f is -0, returns -1.
 If it is zero, returns 1.
 Otherwise returns 0.

$int = cmp2NV($f, $nv);
 $nv can be any perl number - ie NV, UV or IV.
 If the Math::Float128 object $f < $nv returns -1.
 If it is > $nv, returns 1.
 Otherwise returns 0.

LICENSE

This program is free software; you may redistribute it and/or modify
it under the same terms as Perl itself.
Copyright 2013 Sisyphus

AUTHOR

Sisyphus <sisyphus at(@) cpan dot (.) org>