var::matrix

Class for 2d matrix of objects. More...

#include "matrix.hpp"

Public Classes

	Name
struct	LU Struct for PLU decomposition.

Protected Classes

	Name
class	Col Col class for another operator[].

Protected Types

	Name
template <typename T > using std::vector< std::vector< T > >	table 2D vector definition

Public Functions

	Name
	matrix(int r, int c) Construct a new matrix object.
	matrix() Default construct a new matrix object.
	matrix(std::initializer_list< std::initializer_list< D >> a) Construct a new matrix object.
int	row() Returns the number of rows.
int	col() Returns the number of columns.
int	size() Returns total number of elements.
auto	begin() Mainly invoked for the ranged for loop.
auto	end() Returns end of data.
auto	begin() const Returns const begin.
auto	end() const Returns const end.
D	get_element(int i, int j) Get the element object.
std::vector< D >	get_row(int i) Returns the row at an index.
std::vector< D >	get_col(int j) Returns the column at an index.
void	resize(int r, int c) Resizes the matrix.
void	push_row(std::vector< D > a) Inserts row at the end or the matrix.
void	push_col(std::vector< D > a) Inserts column at the end of the matrix.
void	insert_row(int i, std::vector< D > a) Inserts row at specefic index.
void	insert_col(int j, std::vector< D > a) Inserts column at specefic index.
void	pop_row() Removes last row.
void	pop_col() removes last column
void	erase_row(int i) Erase row at index.
void	erase_col(int j) Erases column at index.
void	row_swap(int i1, int i2) Swaps row of matrix.
void	col_swap(int j1, int j2) Colum swap.
void	replace_row(int i, std::vector< D > a) Replaces certain row.
void	replace_col(int j, std::vector< D > a) Replaces certain colum.
void	sort_rows(int d =1) Sorts all rows.
void	sort_cols(int d =1) Sorts all columns.
void	sort_row(int i, int d =1) Sorts rows at specefic index.
void	sort_col(int j, int d =1) Sorts column at specefic index.
template <typename LAMBDA > void	row_op(int i, LAMBDA f) Does operations on specefic rows.
template <typename LAMBDA > void	col_op(int j, LAMBDA f) Does operations on a specefic column.
template <typename LAMBDA > void	mat_op(LAMBDA f) Function operation on all of the matrix.
void	join_row(matrix other) Combines the rows of another matrix.
void	join_col(matrix other) Combines the columns of another matrix.
void	turn_to(D n) Converts all elements to n.
D	sum() Sum of all elements.
D	tr() Trace of a matrix.
D	det() Returns the determinant.
matrix	T() Transpose of a matrix.
matrix	cofactor() Returns cofactor matrix.
matrix	M(int i, int j) Minor of a matrix.
matrix	adj() Adjugate of a matrix.
matrix	inv() Returns inverse of a matrix.
matrix	rref() Reduced row echolon form.
matrix	ref() Row echolon form.
LU	plu() PLU decomposition.
bool	is_square() Checks if matrix is square.
bool	is_empty() Returns if the matrix is empty or not.
bool	is_identity() Checks if matrix is an identity matrix.
Col	operator[](int i) [][] operator for `matrix`
matrix	operator+(const matrix & other) Matrix addition.
matrix	operator+(D n) `matrix+var` as `var` as added to all elements
void	operator+=(matrix a) Increments current matrix by matrix `a`
void	operator+=(D a) Specific variable increment.
void	operator++(int a) Increment operator.
matrix	operator-() Negative of a matrix.
matrix	operator-(const matrix & other) Matrix subtraction.
matrix	operator-(D n) `matrix-var`
void	operator-=(matrix a) Decrement current matrix by matrix `a`
void	operator-=(D a) Decrement current matrix by value `a`
void	operator--(int a) Decrement operator.
matrix	operator*(const matrix & other) Matrix multiplication.
matrix	operator(D n) `matrixvar`
matrix	mathmul(const matrix & other) Normal multiplicatoin.
matrix	operator/(matrix & other) Matrix division using inverse.
matrix	operator/(D n) `matrix/var`
matrix	mathdiv(const matrix & other) Normal math division.
matrix	operator()(int i1, int i2) Returns a sliced matrix.
std::vector< D >	operator()(int i, int j1, int j2) Column per row slicing.
matrix	operator()(int i1, int i2, int j1, int j2) Row and column slice.

Protected Functions

	Name
void	check_col(int j) checks index for columns
void	check_row(int i) checks index for rows
table< D >	TT() Returns transpose for data.
void	check_size(int r, int c) Checks other matrix size for operators.
matrix	MM(int i, int j, matrix & other) Protected minor (used in `DET`)
D	DET(matrix a) Recursive determinant.
void	square() throws exception if matrix is not a square

Friends

	Name
matrix	operator+(D n, matrix & other) `var+matrix`
matrix	operator-(D n, matrix & other) `var-matrix`
matrix	operator(D n, matrix & other) `varmatrix`
matrix	operator/(D n, matrix & other) `var/matrix`

Detailed Description

template <typename D >
class var::matrix;

Class for 2d matrix of objects.

Template Parameters:

D can be of any type

Protected Types Documentation

using table

template <typename T >
using var::matrix< D >::table =  std::vector<std::vector<T> >;

2D vector definition

Template Parameters:

T

Public Functions Documentation

function matrix

inline matrix(
    int r,
    int c
)

Construct a new matrix object.

Parameters:

r number of rows
c number of colums

Usage:

var::matrix<int> m(2, 3); // 2 rows, 3 colums

function matrix

inline matrix()

Default construct a new matrix object.

Usage:

var::matrix<int> m;

function matrix

inline matrix(
    std::initializer_list< std::initializer_list< D >> a
)

Construct a new matrix object.

Usage:

var::matrix<int> m = {
   {1, 2, 3},
   {4, 5, 6},
   {7, 8, 9}
};

Getters

ainitializer list

function row

inline int row()

Returns the number of rows.

Return: int

Usage:

var::matrix<int> m(2, 3);
int r = m.row();

function col

inline int col()

Returns the number of columns.

Return: int

function size

inline int size()

Returns total number of elements.

Return: int

function begin

inline auto begin()

Mainly invoked for the ranged for loop.

Return: std::vector<D>

Usage:

for(auto i: m){
   for(j: i){
     // do smth
   }
}

function end

inline auto end()

Returns end of data.

Return: std::vector<D>

function begin

inline auto begin() const

Returns const begin.

Return: std::vector<D>

function end

inline auto end() const

Returns const end.

Return: std::vector<D>

function get_element

inline D get_element(
    int i,
    int j
)

Get the element object.

Parameters:

i row index
j column index

Return: D

Unlike the [] operator this does index checking

function get_row

inline std::vector< D > get_row(
    int i
)

Returns the row at an index.

Parameters:

i row index

Return: std::vector<D>

Usage:

var::matrix<int> m(3, 3);
auto col = m.get_col(1);

function get_col

inline std::vector< D > get_col(
    int j
)

Returns the column at an index.

Parameters:

j column index

Return: std::vector<D>

Mutable methods

function resize

inline void resize(
    int r,
    int c
)

Resizes the matrix.

Parameters:

r number of rows
c number of colums

Usage:

m.resize(3, 3);

Warning

This resets all elements in the matrix

function push_row

inline void push_row(
    std::vector< D > a
)

Inserts row at the end or the matrix.

Parameters:

a row vector

Usage:

m.push_row({1, 2, 3});

function push_col

inline void push_col(
    std::vector< D > a
)

Inserts column at the end of the matrix.

Parameters:

a column vector

function insert_row

inline void insert_row(
    int i,
    std::vector< D > a
)

Inserts row at specefic index.

Parameters:

i row index
a row vector

Usage:

m.insert_row(1, {1, 2, 3});

function insert_col

inline void insert_col(
    int j,
    std::vector< D > a
)

Inserts column at specefic index.

Parameters:

j column index
a column vector

function pop_row

inline void pop_row()

Removes last row.

Usage:

m.pop_row(1);

function pop_col

inline void pop_col()

removes last column

function erase_row

inline void erase_row(
    int i
)

Erase row at index.

Parameters:

i row index

Usage:

m.erase_row(1);

function erase_col

inline void erase_col(
    int j
)

Erases column at index.

Parameters:

j column index

function row_swap

inline void row_swap(
    int i1,
    int i2
)

Swaps row of matrix.

Parameters:

i1 first row
i2 second row

Usage:

m.row_swap(0, 1); // swaps row 0 with row 1

function col_swap

inline void col_swap(
    int j1,
    int j2
)

Colum swap.

Parameters:

j1 first column
j2 second column

function replace_row

inline void replace_row(
    int i,
    std::vector< D > a
)

Replaces certain row.

Parameters:

i row index
a std::vector

function replace_col

inline void replace_col(
    int j,
    std::vector< D > a
)

Replaces certain colum.

Parameters:

j column index
a std::vector

function sort_rows

inline void sort_rows(
    int d =1
)

Sorts all rows.

Parameters:

d details are shown below
d = 1 is accending order \(\rightarrow\) sort_rows();

d = 0 is decending order \(\rightarrow\) sort_rows(0);

Usage: m.sort_rows(); function sort_cols inline void sort_cols( int d =1 ) Sorts all columns. Parameters: d details are shown below d = 1 is accending order \(\rightarrow\) sort_rows(); d = 0 is decending order \(\rightarrow\) sort_rows(0); function sort_row inline void sort_row( int i, int d =1 ) Sorts rows at specefic index. Parameters: i row index d details are shown below d = 1 is accending order \(\rightarrow\) sort_rows(); d = 0 is decending order \(\rightarrow\) sort_rows(0); Usage: m.sort_row(0, 0); function sort_col inline void sort_col( int j, int d =1 ) Sorts column at specefic index. Parameters: j column index d details are shown below d = 1 is accending order \(\rightarrow\) sort_rows(); d = 0 is decending order \(\rightarrow\) sort_rows(0); function row_op template <typename LAMBDA > inline void row_op( int i, LAMBDA f ) Does operations on specefic rows. Parameters: i column index f function to change column elements Template Parameters: LAMBDA std::function Usage: auto f = [](int A){return A*2+3;}; m.row_op(1, f); function col_op template <typename LAMBDA > inline void col_op( int j, LAMBDA f ) Does operations on a specefic column. Parameters: j column index f function to change column elements Template Parameters: LAMBDA std::function Exception All row and column operations (inserting, removing .. etc) throw an std::invalid_argument if: 1. There is a size mismatch 2. Invalid index function mat_op template <typename LAMBDA > inline void mat_op( LAMBDA f ) Function operation on all of the matrix. Parameters: f Function Template Parameters: LAMBDA std::function Usage: auto f = [](int A){return A*2+3;}; m.mat_op(f); function join_row inline void join_row( matrix other ) Combines the rows of another matrix. Parameters: other matrix Usage: // m2 must have same number of columns as m1 m1.join_row(m2); function join_col inline void join_col( matrix other ) Combines the columns of another matrix. Parameters: other matrix other must have same number of rows function turn_to inline void turn_to( D n ) Converts all elements to n. Parameters: n the specifeid variable Usage: m.turn_to(1); Immutable methods function sum inline D sum() Sum of all elements. Return: D Usage: auto sum = m.sum(); function tr inline D tr() Trace of a matrix. Return: D function det inline D det() Returns the determinant. Return: D function T inline matrix T() Transpose of a matrix. Return: matrix Usage: var::matrix<int> m(3, 3); auto T = m.T(); function cofactor inline matrix cofactor() Returns cofactor matrix. Return: matrix function M inline matrix M( int i, int j ) Minor of a matrix. Parameters: i row index j column index Return: matrix function adj inline matrix adj() Adjugate of a matrix. Return: matrix function inv inline matrix inv() Returns inverse of a matrix. Return: matrix function rref inline matrix rref() Reduced row echolon form. Return: matrix function ref inline matrix ref() Row echolon form. Return: matrix function plu inline LU plu() PLU decomposition. Return: LU Usage: // the output is LU struct auto LU = m.plu(); auto L = LU.L; auto U = LU.U; auto P = LU.p; function is_square inline bool is_square() Checks if matrix is square. Return: true false Usage: bool square = m.is_square(); function is_empty inline bool is_empty() Returns if the matrix is empty or not. Return: true false function is_identity inline bool is_identity() Checks if matrix is an identity matrix. Return: true false Operator methods function operator[] inline Col operator[]( int i ) [][] operator for matrix Parameters: i row index Return: Col which then returns &D Usage: // m[row][col] m[0][0] = 5; Does not check the correct row and colum index; function operator+ inline matrix operator+( const matrix & other ) Matrix addition. Parameters: other Return: matrix Usage: // m1 and m2 are matrix class auto summed = m1+m2; function operator+ inline matrix operator+( D n ) matrix+var as var as added to all elements Parameters: n variable to add Return: matrix Usage: auto m_add_2 = m+2; // or 2+m function operator+= inline void operator+=( matrix a ) Increments current matrix by matrix a Parameters: a matrix Usage: m1+=m2; // m1,m2 -> matrix function operator+= inline void operator+=( D a ) Specific variable increment. Parameters: a increments each value by a Usage: m+=2; // increments every element by 2 function operator++ inline void operator++( int a ) Increment operator. Parameters: a Usage: m++; all values will be increased by 1 function operator- inline matrix operator-() Negative of a matrix. Return: matrix Usage: auto negated = -m; function operator- inline matrix operator-( const matrix & other ) Matrix subtraction. Parameters: other matrix Return: matrix Usage: auto subtracted = m1-m2; function operator- inline matrix operator-( D n ) matrix-var Parameters: n variable to add Return: matrix Usage: auto m_take_2 = m-2; // or 2-m function operator-= inline void operator-=( matrix a ) Decrement current matrix by matrix a Parameters: a matrix Usage: m1 -= m2; function operator-= inline void operator-=( D a ) Decrement current matrix by value a Parameters: a Decrements each value by a Usage: m -= 2; // subtracts each element by 2 function operator-- inline void operator--( int a ) Decrement operator. Parameters: a Usage: m--; // deacreses every value of m by 1 function operator* inline matrix operator*( const matrix & other ) Matrix multiplication. Parameters: other matrix Return: matrix Usage: auto matrix_mul = m*m; function operator* inline matrix operator*( D n ) matrix*var Parameters: n variable multiplying with Return: matrix Usage: auto m_by_2 = m*2; // or 2*m function mathmul inline matrix mathmul( const matrix & other ) Normal multiplicatoin. Parameters: other matrix Return: matrix Usage: auto mul_m = m1.mathmul(m2); function operator/ inline matrix operator/( matrix & other ) Matrix division using inverse. Parameters: other matrix Return: matrix function operator/ inline matrix operator/( D n ) matrix/var Parameters: n our variable Return: matrix Usage: auto m_over_2 = m/2; // 2/m can work function mathdiv inline matrix mathdiv( const matrix & other ) Normal math division. Parameters: other matrix Return: matrix Usage: auto divided = m1.mathdiv(m2); function operator() inline matrix operator()( int i1, int i2 ) Returns a sliced matrix. Parameters: i1 index row 1 (inclusive) i2 index row 2 (exclusive) Return: matrix Usage: // m(inclusive, exclusive) auto sliced = m(1, 3); // row-1 to row-2 function operator() inline std::vector< D > operator()( int i, int j1, int j2 ) Column per row slicing. Parameters: i row index j1 column index 1 (inclusive) j2 column index 2 (exclusive) Return: std::vector<D> Condition j2 >= j1 must be true. function operator() inline matrix operator()( int i1, int i2, int j1, int j2 ) Row and column slice. Parameters: i1 row index 1 (inclusive) i2 row index 2 (exclusive) j1 column index 1 (inclusive) j2 column index 2 (exclusive) Return: matrix Exception All () operators will throw an std::invalid_argument unless: Index is correct and valid \(i_2 \geq i_1\) and \(j_2 \geq j_1\) Protected Functions Documentation function check_col inline void check_col( int j ) checks index for columns Parameters: j column index function check_row inline void check_row( int i ) checks index for rows Parameters: i row index function TT inline table< D > TT() Returns transpose for data. Return: table<D> function check_size inline void check_size( int r, int c ) Checks other matrix size for operators. Parameters: r row c column function MM inline matrix MM( int i, int j, matrix & other ) Protected minor (used in DET) Parameters: i row index j column index other matrix Return: matrix function DET inline D DET( matrix a ) Recursive determinant. Parameters: a matrix type Return: D function square inline void square() throws exception if matrix is not a square Friends friend operator+ friend matrix operator+( D n, matrix & other ); var+matrix Parameters: n variable to add other matrix Return: matrix friend operator- friend matrix operator-( D n, matrix & other ); var-matrix Parameters: n variable to add other matrix Return: matrix friend operator* friend matrix operator*( D n, matrix & other ); var*matrix Parameters: n variable multiplying with other matrix Return: matrix friend operator/ friend matrix operator/( D n, matrix & other ); var/matrix Parameters: n our variable other matrix Return: matrix Updated on 4 September 2022 at 18:30:41 EEST