CGAL::Gmpz Class Reference

#include <CGAL/Gmpz.h>

Definition

An object of the class Gmpz is an arbitrary precision integer based on the GMP Library.

Is model of

EuclideanRing

RealEmbeddable

Implementation

Gmpzs are reference counted.

Related Functions
(Note that these are not member functions.)
Gmpz	operator>> (const Gmpz &a, unsigned long i)
	rightshift by i.
Gmpz	operator<< (const Gmpz &a, unsigned long i)
	leftshift by i.
Gmpz	operator& (const Gmpz &a, const Gmpz &b)
	bitwise AND.
Gmpz	operator| (const Gmpz &a, const Gmpz &b)
	bitwise IOR.
Gmpz	operator^ (const Gmpz &a, const Gmpz &b)
	bitwise XOR.
std::ostream &	operator<< (std::ostream &out, const Gmpz &z)
	writes z to the ostream out.
std::istream &	operator>> (std::istream &in, Gmpz &z)
	reads an integer from in, then converts it to a Gmpz.

Creation
	Gmpz ()
	creates an uninitialized multiple precision integer z.
	Gmpz (int i)
	creates a multiple-precision integer initialized with i.
	Gmpz (double d)
	creates a multiple-precision integer initialized with the integral part of d.

Operations
Gmpz &	operator++ ()
	prefix increment.
Gmpz	operator++ (int)
	postfix increment.
Gmpz &	operator-- ()
	prefix decrement.
Gmpz	operator-- (int)
	postfix decrement.
Gmpz &	operator>>= (const long &i)
	rightshift by i, where i >= 0.
Gmpz &	operator<<= (const long &i)
	leftshift by i, where i >= 0.
Gmpz &	operator&= (const Gmpz &b)
	bitwise AND.
Gmpz &	operator|= (const Gmpz &b)
	bitwise IOR.
Gmpz &	operator^= (const Gmpz &b)
	bitwise XOR.
Sign	sign () const
	Returns the sign of z.
size_t	bit_size () const
	Returns the bit-size (that is, the number of bits needed to represent the mantissa) of z.
size_t	size () const
	Returns the size in limbs of z.
size_t	approximate_decimal_length () const
	Returns the approximate number of decimal digits needed to represent z.
double	to_double () const
	Returns a double approximation of z.

Member Function Documentation

approximate_decimal_length()

size_t CGAL::Gmpz::approximate_decimal_length

(

)

const

Returns the approximate number of decimal digits needed to represent z.

Approximate means either a correct result, either the correct result plus one.

size()

size_t CGAL::Gmpz::size

(

)

const

Returns the size in limbs of z.

A limb is the type used by GMP to represent the integer (usually long).

to_double()

double CGAL::Gmpz::to_double

(

)

const

Returns a double approximation of z.

The integer is truncated if needed. If the exponent of the conversion is too big, the result is system dependent (returning infinity where it is supported).