Math::BigFloat - Arbitrary length float math package
use Math::BigFloat;
$f = Math::BigFloat->new($string);
$f->fadd(NSTR) return NSTR addition
$f->fsub(NSTR) return NSTR subtraction
$f->fmul(NSTR) return NSTR multiplication
$f->fdiv(NSTR[,SCALE]) returns NSTR division to SCALE places
$f->fmod(NSTR) returns NSTR modular remainder
$f->fneg() return NSTR negation
$f->fabs() return NSTR absolute value
$f->fcmp(NSTR) return CODE compare undef,<0,=0,>0
$f->fround(SCALE) return NSTR round to SCALE digits
$f->ffround(SCALE) return NSTR round at SCALEth place
$f->fnorm() return (NSTR) normalize
$f->fsqrt([SCALE]) return NSTR sqrt to SCALE places
All basic math operations are overloaded if you declare your big
floats as
$float = new Math::BigFloat "2.123123123123123123123123123123123";
- number format
-
canonical strings have the form /[+-]\d+E[+-]\d+/ . Input values can
have embedded whitespace.
- Error returns 'NaN'
-
An input parameter was ``Not a Number'' or divide by zero or sqrt of
negative number.
- Division is computed to
-
max($Math::BigFloat::div_scale,length(dividend)+length(divisor))
digits by default.
Also used for default sqrt scale.
- Rounding is performed
-
according to the value of
$Math::BigFloat::rnd_mode:
trunc truncate the value
zero round towards 0
+inf round towards +infinity (round up)
-inf round towards -infinity (round down)
even round to the nearest, .5 to the even digit
odd round to the nearest, .5 to the odd digit
The default is even rounding.
The current version of this module is a preliminary version of the
real thing that is currently (as of perl5.002) under development.
The printf subroutine does not use the value of
$Math::BigFloat::rnd_mode when rounding values for printing.
Consequently, the way to print rounded values is
to specify the number of digits both as an
argument to ffround and in the %f printf string,
as follows:
printf "%.3f\n", $bigfloat->ffround(-3);
Mark Biggar
Patches by John Peacock Apr 2001
=cut
