Math::BigRat
- NAME
- SYNOPSIS
- DESCRIPTION
- METHODS
- new()
- numerator()
- denominator()
- parts()
- numify()
- as_int()/as_number()
- as_float()
- as_hex()
- as_bin()
- as_oct()
- from_hex()/from_bin()/from_oct()
- length()
- digit()
- bnorm()
- bfac()
- bround()/round()/bfround()
- bmod()
- bneg()
- is_one()
- is_zero()
- is_pos()/is_positive()
- is_neg()/is_negative()
- is_int()
- is_odd()
- is_even()
- bceil()
- bfloor()
- bsqrt()
- broot()
- badd()/bmul()/bsub()/bdiv()/bdec()/binc()
- copy()
- bstr()/bsstr()
- bacmp()/bcmp()
- blsft()/brsft()
- bpow()
- bexp()
- bnok()
- config()
- objectify()
- BUGS
- SUPPORT
- LICENSE
- SEE ALSO
- AUTHORS
NAME
Math::BigRat - Arbitrary big rational numbers
SYNOPSIS
DESCRIPTION
Math::BigRat complements Math::BigInt and Math::BigFloat by providing support for arbitrary big rational numbers.
MATH LIBRARY
You can change the underlying module that does the low-level math operations by using:
- use Math::BigRat try => 'GMP';
Note: This needs Math::BigInt::GMP installed.
The following would first try to find Math::BigInt::Foo, then Math::BigInt::Bar, and when this also fails, revert to Math::BigInt::Calc:
- use Math::BigRat try => 'Foo,Math::BigInt::Bar';
If you want to get warned when the fallback occurs, replace "try" with "lib":
- use Math::BigRat lib => 'Foo,Math::BigInt::Bar';
If you want the code to die instead, replace "try" with "only":
- use Math::BigRat only => 'Foo,Math::BigInt::Bar';
METHODS
Any methods not listed here are derived from Math::BigFloat (or Math::BigInt), so make sure you check these two modules for further information.
new()
- $x = Math::BigRat->new('1/3');
Create a new Math::BigRat object. Input can come in various forms:
- $x = Math::BigRat->new(123); # scalars
- $x = Math::BigRat->new('inf'); # infinity
- $x = Math::BigRat->new('123.3'); # float
- $x = Math::BigRat->new('1/3'); # simple string
- $x = Math::BigRat->new('1 / 3'); # spaced
- $x = Math::BigRat->new('1 / 0.1'); # w/ floats
- $x = Math::BigRat->new(Math::BigInt->new(3)); # BigInt
- $x = Math::BigRat->new(Math::BigFloat->new('3.1')); # BigFloat
- $x = Math::BigRat->new(Math::BigInt::Lite->new('2')); # BigLite
- # You can also give D and N as different objects:
- $x = Math::BigRat->new(
- Math::BigInt->new(-123),
- Math::BigInt->new(7),
- ); # => -123/7
numerator()
- $n = $x->numerator();
Returns a copy of the numerator (the part above the line) as signed BigInt.
denominator()
- $d = $x->denominator();
Returns a copy of the denominator (the part under the line) as positive BigInt.
parts()
- ($n,$d) = $x->parts();
Return a list consisting of (signed) numerator and (unsigned) denominator as BigInts.
numify()
- my $y = $x->numify();
Returns the object as a scalar. This will lose some data if the object cannot be represented by a normal Perl scalar (integer or float), so use as_int() or as_float() instead.
This routine is automatically used whenever a scalar is required:
- my $x = Math::BigRat->new('3/1');
- @array = (0,1,2,3);
- $y = $array[$x]; # set $y to 3
as_int()/as_number()
- $x = Math::BigRat->new('13/7');
- print $x->as_int(),"\n"; # '1'
Returns a copy of the object as BigInt, truncated to an integer.
as_number()
is an alias for as_int()
.
as_float()
Returns a copy of the object as BigFloat, preserving the accuracy as wanted, or the default of 40 digits.
This method was added in v0.22 of Math::BigRat (April 2008).
as_hex()
- $x = Math::BigRat->new('13');
- print $x->as_hex(),"\n"; # '0xd'
Returns the BigRat as hexadecimal string. Works only for integers.
as_bin()
- $x = Math::BigRat->new('13');
- print $x->as_bin(),"\n"; # '0x1101'
Returns the BigRat as binary string. Works only for integers.
as_oct()
- $x = Math::BigRat->new('13');
- print $x->as_oct(),"\n"; # '015'
Returns the BigRat as octal string. Works only for integers.
from_hex()/from_bin()/from_oct()
Create a BigRat from an hexadecimal, binary or octal number in string form.
length()
- $len = $x->length();
Return the length of $x in digits for integer values.
digit()
Return the N'ths digit from X when X is an integer value.
bnorm()
- $x->bnorm();
Reduce the number to the shortest form. This routine is called automatically whenever it is needed.
bfac()
- $x->bfac();
Calculates the factorial of $x. For instance:
Works currently only for integers.
bround()/round()/bfround()
Are not yet implemented.
bmod()
Set $x to the remainder of the division of $x by $y.
bneg()
- $x->bneg();
Used to negate the object in-place.
is_one()
Return true if $x is exactly one, otherwise false.
is_zero()
Return true if $x is exactly zero, otherwise false.
is_pos()/is_positive()
Return true if $x is positive (greater than or equal to zero), otherwise false. Please note that '+inf' is also positive, while 'NaN' and '-inf' aren't.
is_positive()
is an alias for is_pos()
.
is_neg()/is_negative()
Return true if $x is negative (smaller than zero), otherwise false. Please note that '-inf' is also negative, while 'NaN' and '+inf' aren't.
is_negative()
is an alias for is_neg()
.
is_int()
Return true if $x has a denominator of 1 (e.g. no fraction parts), otherwise false. Please note that '-inf', 'inf' and 'NaN' aren't integer.
is_odd()
Return true if $x is odd, otherwise false.
is_even()
Return true if $x is even, otherwise false.
bceil()
- $x->bceil();
Set $x to the next bigger integer value (e.g. truncate the number to integer and then increment it by one).
bfloor()
- $x->bfloor();
Truncate $x to an integer value.
bsqrt()
- $x->bsqrt();
Calculate the square root of $x.
broot()
- $x->broot($n);
Calculate the N'th root of $x.
badd()/bmul()/bsub()/bdiv()/bdec()/binc()
Please see the documentation in Math::BigInt.
copy()
- my $z = $x->copy();
Makes a deep copy of the object.
Please see the documentation in Math::BigInt for further details.
bstr()/bsstr()
Return a string representing this object.
bacmp()/bcmp()
Used to compare numbers.
Please see the documentation in Math::BigInt for further details.
blsft()/brsft()
Used to shift numbers left/right.
Please see the documentation in Math::BigInt for further details.
bpow()
- $x->bpow($y);
Compute $x ** $y.
Please see the documentation in Math::BigInt for further details.
bexp()
- $x->bexp($accuracy); # calculate e ** X
Calculates two integers A and B so that A/B is equal to e ** $x
, where e
is
Euler's number.
This method was added in v0.20 of Math::BigRat (May 2007).
See also blog()
.
bnok()
- $x->bnok($y); # x over y (binomial coefficient n over k)
Calculates the binomial coefficient n over k, also called the "choose" function. The result is equivalent to:
- ( n ) n!
- | - | = -------
- ( k ) k!(n-k)!
This method was added in v0.20 of Math::BigRat (May 2007).
config()
Returns a hash containing the configuration, e.g. the version number, lib loaded etc. The following hash keys are currently filled in with the appropriate information.
- key RO/RW Description
- Example
- ============================================================
- lib RO Name of the Math library
- Math::BigInt::Calc
- lib_version RO Version of 'lib'
- 0.30
- class RO The class of config you just called
- Math::BigRat
- version RO version number of the class you used
- 0.10
- upgrade RW To which class numbers are upgraded
- undef
- downgrade RW To which class numbers are downgraded
- undef
- precision RW Global precision
- undef
- accuracy RW Global accuracy
- undef
- round_mode RW Global round mode
- even
- div_scale RW Fallback accuracy for div
- 40
- trap_nan RW Trap creation of NaN (undef = no)
- undef
- trap_inf RW Trap creation of +inf/-inf (undef = no)
- undef
By passing a reference to a hash you may set the configuration values. This
works only for values that a marked with a RW
above, anything else is
read-only.
objectify()
This is an internal routine that turns scalars into objects.
BUGS
Please report any bugs or feature requests to
bug-math-bigrat at rt.cpan.org
, or through the web interface at
https://rt.cpan.org/Ticket/Create.html?Queue=Math-BigRat
(requires login).
We will be notified, and then you'll automatically be notified of progress on
your bug as I make changes.
SUPPORT
You can find documentation for this module with the perldoc command.
- perldoc Math::BigRat
You can also look for information at:
- RT: CPAN's request tracker
https://rt.cpan.org/Public/Dist/Display.html?Name=Math-BigRat
- AnnoCPAN: Annotated CPAN documentation
- CPAN Ratings
- Search CPAN
- CPAN Testers Matrix
- The Bignum mailing list
LICENSE
This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
bigrat, Math::BigFloat and Math::BigInt as well as the backends Math::BigInt::FastCalc, Math::BigInt::GMP, and Math::BigInt::Pari.
AUTHORS
(C) by Tels http://bloodgate.com/ 2001 - 2009.
Currently maintained by Jonathan "Duke" Leto <jonathan@leto.net> http://leto.net
- NAME
- SYNOPSIS
- DESCRIPTION
- METHODS
- new()
- numerator()
- denominator()
- parts()
- numify()
- as_int()/as_number()
- as_float()
- as_hex()
- as_bin()
- as_oct()
- from_hex()/from_bin()/from_oct()
- length()
- digit()
- bnorm()
- bfac()
- bround()/round()/bfround()
- bmod()
- bneg()
- is_one()
- is_zero()
- is_pos()/is_positive()
- is_neg()/is_negative()
- is_int()
- is_odd()
- is_even()
- bceil()
- bfloor()
- bsqrt()
- broot()
- badd()/bmul()/bsub()/bdiv()/bdec()/binc()
- copy()
- bstr()/bsstr()
- bacmp()/bcmp()
- blsft()/brsft()
- bpow()
- bexp()
- bnok()
- config()
- objectify()
- BUGS
- SUPPORT
- LICENSE
- SEE ALSO
- AUTHORS