Matrices. More...

#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>

Data Structures
struct	_Matrix
	Defination of a _Matrix structure to hold the matrix entries. More...

Typedefs
typedef struct _Matrix	Matrix
	Repersents the structure which holds the matrix. More...

Functions
void	matrix_print (Matrix *matrix)
	Print whole entire matrix to stdout. More...

void	matrix_fill (Matrix *matrix)
	This fills the entire matrix with values which are inputed in the terminal. More...

Matrix *	matrix_callalloc (int matrix_size)
	Creates an identity matrix that is all the diagonal entries are initialised to 1 and all other entries to zero). More...

Matrix *	matrix_alloc (int row_size, int col_size)
	Allocates memory for a new matrix. More...

void	matrix_copy (Matrix matrix1, Matrix matrix2)
	Copies the content of one matrix1 into matrix2. More...

Matrix *	matrix_multiply (const Matrix matrix1, const Matrix matrix2)
	Multiplies two matrices. More...

Matrix *	matrix_pow (Matrix *matrix, int index)
	Multiplies a matrix by itself 'n' times. More...

void	matrix_free (Matrix *matrix)
	Free an entire matrix. More...

void	row_divide (Matrix *matrix, int pivot)
	Divides an entire row of a matrix by a value of the pivot position. More...

void	row_operation (Matrix multiplier_matrix, Matrix matrix, int pivot, int row_index)
	Row operations on the matrix. More...

void	matrix_row_reduce (Matrix *matrix, int zero_control)
	Row echelon reduction a matrix. More...

void	matrix_print_part (Matrix *matrix, int start_index)
	Printing some columns of a matrix. More...

void	LU_decompose (Matrix upper_triangular, Matrix lower_triangular)
	This function performs the LU decomposition of a matrix. More...

void	terminate (char *string)
	Fucntion to terminate an application in case of an error. More...

void	matrix_subtract (Matrix result, Matrix matrix1, Matrix *matrix2)
	Subtracts one matrix from another. More...

void	matrix_add (Matrix result, Matrix matrix1, Matrix *matrix2)
	Adds one matrix to another. More...

void	matrix_invert (Matrix *inverse_matrix)
	Perform the inverse of a matrix. More...

int	matrix_equal_size (Matrix matrix1, Matrix matrix2)
	Checks if two matrices have equal rows and columns. More...

Detailed Description

Matrices.

This header file contains all the functions which can be used to manipulate the matrices so as to obtain required outputs.

To create a new matrix, you will have to allocate space for the matrix using matrix_alloc or matrix_callalloc

To copy a matrix into another, use matrix_copy.

To multiply two matrices, use matrix_multiply.

To multiply a matrix by itself 'n' times (ie raise the matrix to the nth power) use matrix_pow.

To add or subtract two matrices, use matrix_add or matrix_subtract respectively.

To perform LU decompostion of a matrix, use LU_decompose.

To perform row echelon reduction of a particular matrix, use matrix_row_reduce.

To print the matrix at any time, use matrix_print or matrix_print_part

The fuction row_divide is used as an accesory function in other functions to divide a row of a matrix by a specific value.

The function row_operation is used as an accesory function in other functions to perform row operations on a matrix.

The function matrix_equal_size checks if two matrices have the same number or rows and columns

Typedef Documentation

typedef struct _Matrix Matrix

Repersents the structure which holds the matrix.

to initialise a new Matrix, simply create a variable of this type and initialise to NULL if neccesary

See Also: matrix_alloc

Function Documentation

void LU_decompose	(	Matrix *	upper_triangular,
		Matrix *	lower_triangular
	)

This function performs the LU decomposition of a matrix.

Parameters

upper_triangular	A pionter to the matrix on which to perform LU decomposition.
lower_triangular	A pointer to the lower triangular matrix

Note: You should allocate memory for the lower_triangular matrix with matrix_callalloc before passing it to this function

void matrix_add	(	Matrix *	result,
		Matrix *	matrix1,
		Matrix *	matrix2
	)

Adds one matrix to another.

Parameters

result	A matrix to hold the result of the addition
matrix1	The first matrix for the addition
matrix2	The second matrix for the addition

Matrix* matrix_alloc	(	int	row_size,
		int	col_size
	)

Allocates memory for a new matrix.

Parameters

row_size	The number of rows in the matrix
col_size	The number of columns in the matrix

Returns: The location of the memory block that was allocated to hold the matrix

Matrix* matrix_callalloc ( int matrix_size )

Creates an identity matrix that is all the diagonal entries are initialised to 1 and all other entries to zero).

Parameters

matrix_size The number of rows and columns in the identity matrix.

Returns: A pointer to the new identity matrix just created

void matrix_copy	(	Matrix *	matrix1,
		Matrix *	matrix2
	)

Copies the content of one matrix1 into matrix2.

Parameters

matrix1	Pointer the matrix to be copied
matrix2	Pointer to the matrix to which the other is to be copied into

int matrix_equal_size	(	Matrix *	matrix1,
		Matrix *	matrix2
	)

Checks if two matrices have equal rows and columns.

Parameters

matrix1	The first matrix
matrix2	The second matrix

Returns: Non-zero if the matrix row and columns are equal, zero if they are not equal.

void matrix_fill ( Matrix * matrix )

This fills the entire matrix with values which are inputed in the terminal.

Parameters

matrix Pointer to the matrix structure which is to be filled.

void matrix_free ( Matrix * matrix )

Free an entire matrix.

Parameters

matrix The matrix to free.

void matrix_invert ( Matrix * inverse_matrix )

Perform the inverse of a matrix.

Parameters

inverse_matrix The matrix which is to be inverted

Matrix* matrix_multiply	(	const Matrix *	matrix1,
		const Matrix *	matrix2
	)

Multiplies two matrices.

Parameters

matrix1	Pointer to the first matrix for the multiplication
matrix2	The second matrix for the multiplication

Returns: The location of a matrix which holds the result of the multiplication

Matrix* matrix_pow	(	Matrix *	matrix,
		int	index
	)

Multiplies a matrix by itself 'n' times.

Parameters

matrix	The matrix which is to self multiplied 'n' times
index	The number of times the matrix is to be multiplied to itself

Returns: The location of the matrix which holds the results of the multiplications

void matrix_print ( Matrix * matrix )

Print whole entire matrix to stdout.

Parameters

matrix Pointer to the matrix to be printed to stdout

void matrix_print_part	(	Matrix *	matrix,
		int	start_index
	)

Printing some columns of a matrix.

Parameters

matrix	The matrix whose part is to be printed
start_index	The column number to start printing from

void matrix_row_reduce	(	Matrix *	matrix,
		int	zero_control
	)

Row echelon reduction a matrix.

Parameters

matrix	The matrix on which to carry out row reduction
zero_control	Maximum amount of zeros that can be found on a row

void matrix_subtract	(	Matrix *	result,
		Matrix *	matrix1,
		Matrix *	matrix2
	)

Subtracts one matrix from another.

Parameters

result	A matrix to hold the result of the subraction
matrix1	The matrix to subtract from
matrix2	The matrix to be subtrated from another

void row_divide	(	Matrix *	matrix,
		int	pivot
	)

Divides an entire row of a matrix by a value of the pivot position.

Parameters

matrix	The matrix whose row is to be divided
pivot	The pivot postion of the matrix to do the division

void row_operation	(	Matrix *	multiplier_matrix,
		Matrix *	matrix,
		int	pivot,
		int	row_index
	)

Row operations on the matrix.

Parameters

multiplier_matrix	A matrix to store the various multipliers used in row reduction
matrix	A matrix on which to carry out the row operations
pivot	The pivot position of the matrix to use
row_index	The row number on which to carry out row operations

void terminate ( char * string )

Fucntion to terminate an application in case of an error.

Parameters

string Message to displayed to stdout in case of an error

Data Structures

Typedefs

Functions

Detailed Description

Typedef Documentation

Function Documentation