atlas::size::SizeType< C > Class Template Reference

Stores a positive integer as product of prime powers, using the first PRIMES_MAX primes. More...

#include <Atlas.h>

Public Member Functions
	SizeType ()
	SizeType (unsigned long)
C	operator[] (size_t j) const
bool	operator== (const SizeType &c) const
bool	operator!= (const SizeType &c) const
unsigned long	piece (size_t) const
unsigned long	toUlong () const
C &	operator[] (size_t j)
SizeType &	operator*= (const SizeType &)
SizeType &	operator*= (unsigned long n)
SizeType &	operator/= (const SizeType &)
void	reset ()
void	twoShift (C n)

Private Attributes
C	d_exp [PRIMES_MAX]

Detailed Description

template<typename C>
class atlas::size::SizeType< C >

Stores a positive integer as product of prime powers, using the first PRIMES_MAX primes.

The exponent of the jth prime is |d_exp[j]|. The reason for using this is that the software must occasionally deal with integers too large to be unsigned long; mostly these appear as cardinalities of Weyl groups. The constant |PRIMES_MAX| is chosen so that the cardinality of any Weyl group of rank at most RANK_MAX can be represented as a |SizeType|.

Constructor & Destructor Documentation

template<typename C >

atlas::size::SizeType< C >::SizeType ( )

inline

template<typename C >

atlas::size::SizeType< C >::SizeType ( unsigned long  a )

explicit

Synopsis: constructs the SizeType object representing value |a|.

Triggers a fatal error if a is not representable as a SizeType

Member Function Documentation

template<typename C >

bool atlas::size::SizeType< C >::operator!= ( const SizeType< C > &  c ) const

inline

template<typename C >

SizeType< C > & atlas::size::SizeType< C >::operator*=

(

const SizeType< C > &

a

)

NOTE: multiplication becomes addition in our logarithmic representation.

template<typename C >

SizeType& atlas::size::SizeType< C >::operator*= ( unsigned long  n )

inline

template<typename C >

SizeType< C > & atlas::size::SizeType< C >::operator/=

(

const SizeType< C > &

a

)

NOTE: division becomes subtraction in our logarithmic representation.

template<typename C >

bool atlas::size::SizeType< C >::operator== ( const SizeType< C > &  c ) const

inline

template<typename C >

C atlas::size::SizeType< C >::operator[] ( size_t  j ) const

inline

template<typename C >

C& atlas::size::SizeType< C >::operator[] ( size_t  j )

inline

template<typename C >

unsigned long atlas::size::SizeType< C >::piece

(

size_t

k

)

const

Synopsis: return the unsigned long value of $prime(i)^{d_exp[i]}$

The algorithm is the classical algorithm with squarings and multiplications, logarithmic in i.

NOTE: in case of overflow, we simply return the value modulo $2^{longBits}$.

template<typename C >

void atlas::size::SizeType< C >::reset ( )

inline

template<typename C >

unsigned long atlas::size::SizeType< C >::toUlong

(

)

const

Synopsis: returns the unsigned long value of *this.

NOTE: in case of overflow, we simply return the value modulo $2^{longBits}$.

template<typename C >

void atlas::size::SizeType< C >::twoShift ( C  n )

inline

Member Data Documentation

template<typename C >

C atlas::size::SizeType< C >::d_exp[PRIMES_MAX]

private

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The documentation for this class was generated from the following files:

• /home/ran/atlas_project/latest_branch_07182016/sources/Atlas.h
• /home/ran/atlas_project/latest_branch_07182016/sources/utilities/size.h
• /home/ran/atlas_project/latest_branch_07182016/sources/utilities/size.cpp