CECCO::DEMUX< E, S > Class Template Reference

Field demultiplexer — expand 𝔽_E elements into 𝔽_S coefficient vectors/matrices. More...

#include <blocks.hpp>

Inheritance diagram for CECCO::DEMUX< E, S >:

Public Member Functions
constexpr	DEMUX ()=default
constexpr Vector< S >	operator() (const E &in)
	Expand a single element into its subfield-coefficient vector.
Matrix< S >	operator() (const Vector< E > &in)
	Expand a vector of elements into a subfield-coefficient matrix.

Detailed Description

template<FiniteFieldType E, FiniteFieldType S>
requires (SubfieldOf<E, S>)
class CECCO::DEMUX< E, S >

Field demultiplexer — expand 𝔽_E elements into 𝔽_S coefficient vectors/matrices.

Template Parameters

E	Extension field
S	Subfield of E (S ⊆ E)

Each E element decomposes into [E:S] coefficients over S via the polynomial basis of the extension. For a Vector<E> of length n, the resulting Matrix<S> has [E:S] rows and n columns; column j holds the coefficients of element j.

using F2 = Fp<2>;
using F4 = Ext<F2, {1, 1, 1}>;          // 𝔽_4 = 𝔽_2[x]/(x² + x + 1)
DEMUX<F4, F2> demux;
 
Vector<F4> v = {F4(0), F4(1), F4(2), F4(3)};
Matrix<F2> M = v >> demux;              // 2×4 matrix over 𝔽_2

See also

CECCO::MUX for the inverse

CECCO::Ext, CECCO::SubfieldOf

Definition at line 860 of file blocks.hpp.

Constructor & Destructor Documentation

DEMUX()

template<FiniteFieldType E, FiniteFieldType S>

CECCO::DEMUX< E, S >::DEMUX ( )

constexprdefault

Member Function Documentation

operator()() [1/2]

template<FiniteFieldType E, FiniteFieldType S>

Vector< S > CECCO::DEMUX< E, S >::operator() ( const E & in )

inlineconstexpr

Expand a single element into its subfield-coefficient vector.

Parameters

in	Extension field element

Returns

Length-[E:S] vector of S coefficients

Definition at line 869 of file blocks.hpp.

operator()() [2/2]

template<FiniteFieldType E, FiniteFieldType S>

Matrix< S > CECCO::DEMUX< E, S >::operator()

(

const Vector< E > &

in

)

Expand a vector of elements into a subfield-coefficient matrix.

Parameters

in	Vector of n extension field elements

Returns

[E:S] × n matrix; column j holds the coefficients of in[j]

Definition at line 881 of file blocks.hpp.

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

• blocks.hpp