libsemigroups::pbr Namespace Reference

This namespace contains helper functions for the PBR class.

Functions
PBR	one (PBR const &x)
	Returns the identity PBR with degree x.degree().
PBR	one (size_t n)
	Returns the identity PBR with specified degree.
void	throw_if_adjacencies_unsorted (PBR const &x)
	Throws if a PBR has a list of points related to a point that is not sorted.
void	throw_if_entry_out_of_bounds (PBR const &x)
	Throws if a PBR has a point related to a point that is greater than degree().
void	throw_if_invalid (PBR const &x)
	Throws if a PBR is invalid.
void	throw_if_not_even_length (PBR const &x)
	Throws if a PBR has an odd number of points.

Function Documentation

one() [1/2]

PBR one

(

PBR const &

x

)

This member function returns a new PBR with degree equal to the degree of x, where every value is adjacent to its negative. Equivalently, $i$ is adjacent $i+n$ and vice versa for every $i$ less than the degree $n$.

Parameters

x

A PBR.

Returns

A PBR.

Exceptions

This function guarantees not to throw a LibsemigroupsException.

See also

one(size_t)

one() [2/2]

PBR one

(

size_t

n

)

This function returns a new PBR with degree equal to n where every value is adjacent to its negative. Equivalently, $i$ is adjacent $i+n$ and vice versa for every $i$ less than the degree $n$.

Parameters

n	the degree.

Returns

A PBR.

Exceptions

This function guarantees not to throw a LibsemigroupsException.

See also

one(PBR const&)

throw_if_adjacencies_unsorted()

void throw_if_adjacencies_unsorted

(

PBR const &

x

)

This function throws a LibsemigroupsException if the argument x has a list of points related to a point that is not sorted.

Parameters

x	the PBR to check.

Exceptions

LibsemigroupsException

if x has a list of points related to a point that is not sorted.

Complexity

Linear in the PBR::degree of x.

throw_if_entry_out_of_bounds()

void throw_if_entry_out_of_bounds

(

PBR const &

x

)

This function throws a LibsemigroupsException if the argument x has a point related to a point that is greater than degree().

Parameters

x	the PBR to check.

Exceptions

LibsemigroupsException

if x has a point related to a point that is greater than degree().

Complexity

Linear in the PBR::degree of x.

throw_if_invalid()

void throw_if_invalid ( PBR const & x )

inline

This function throws a LibsemigroupsException if the argument x is not a valid PBR.

Parameters

x	the PBR to check.

Exceptions

LibsemigroupsException

if any of the following occur: x does not describe a binary relation on an even number of points; x has a point related to a point that is greater than degree(); a list of points related to a point is not sorted.

Complexity

Linear in the PBR::degree x.

See also

• throw_if_not_even_length(PBR const&);
• throw_if_entry_out_of_bounds(PBR const&);
• throw_if_adjacencies_unsorted(PBR const&).

throw_if_not_even_length()

void throw_if_not_even_length

(

PBR const &

x

)

This function throws a LibsemigroupsException if the argument x does not describe a binary relation on an even number of points.

Parameters

x	the PBR to check.

Exceptions

LibsemigroupsException

x does not describe a binary relation on an even number of points.

Complexity

Constant.