Matrices

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Matrices in the C language. This project was made with the aim of creating a library where there will be simple operations for working with matrices.

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• matrix
• creating a matrix
• removing the matrix
• comparison
• matrix addition
• matrix subtraction
• Multiplying a matrix by a number
• two-matrix multiplication
• Matrix transposition
• matrix of algebraic additions
• determinant
• inverse matrix
• library

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matrix

matrix as a data type

The matrix is pressed as a structure - matrix_t

typedef struct matrix_struct {
  double **matrix;
  int rows;
  int columns;
} matrix_t;

Example of creating a matrix as a data type:

int main() {
    matrix_t my_matrix;
}

Many functions accept a result matrix. The result matrix should be empty.

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creating a matrix

To create a matrix, you need to call the function MatrixCreate() and pass three arguments there - the required number of rows, columns, the data type itself (its address). The function will return 0 if everything is completed successfully.

matrix_t my_matrix;
int fail = MatrixCreate(4, 4, &my_matrix);

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removing the matrix

To delete a matrix, call the function MatrixRemove(). The function takes on one parameter - matrix_t If memory is not allocated, the data type is protected from deletion if it contains NULL; In case its contents were changed incorrectly, outside of these functions, make an error while the program is running.

int main() {
matrix_t my_matrix;
int fail = MatrixCreate(4, 4, &my_matrix);
MatrixRemove(&my_matrix);
}

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Comparison

Comparison of two matrices. To compare two matrices, you need to call the function MatrixEq() and pass two matrices to it as two arguments.

#define SUCCESS 1
#define FAILURE 0 

int succes = (MatrixEq(&my_matrix, &other_matrix) == 1) ? SUCCESS : FAILURE;

The function will return 1 if the matrices are equal, otherwise 0;

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Matrix addition

To add two matrices, use the function MatrixSum(). Pass three arguments to it, the last of which will be the result of addition. The function will return one if there is an error.

matrix_t result;
int fail = MatrixSum(&matrix_one, &matrix_two, &result);

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Matrix subtraction

To subtract two matrices, use the function MatrixSub(). Pass three arguments to it, the last of which will be the result of subtraction. The function will return one if there is an error.

matrix_t result;
int fail = MatrixSub(&matrix_one, &matrix_two, &result);

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Multiplying a matrix by a number

To multiply a matrix by a number, use the function MatrixMultNum(). The function takes three parameters, the first is a matrix, the second is a number, and the third is the returned result. The function will return a number other than 0 - if there is an error (or it will be impossible to multiply two matrices).

double other_num = 5.3;
matrix_t result;
int fail = MatrixMultNum(&my_matrix, other_num, &result);

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Multiplication of two matrices

To multiply two matrices, use the function MatrixMultMatrix(). The function takes three parameters, all matrices the last one is the result matrix. The function returns 0 if everything was successful.

matrix_t result;
int fail = MatrixMultNum(&my_matrix, &other_matrix, &result);

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Matrix transposition

To get the transposed matrix in the function MatrixTranspose() pass two arguments, the first is your matrix. The second is the result matrix.

matrix_t result;
int fail = MatrixTranspose(&my_matrix, &result);

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Matrix of algebraic additions

To get the matrix of algebraic complements, use the function ``MatrixCalcComplements()`'. The first argument of the function is your matrix. The second argument of the function is the result matrix.

matrix_t result;
int fail = MatrixCalcComplements(&my_matrix, &result);

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Determinant

I used recursion to find

In order to find the determinant of the matrix (determinant), use the function MatrixDet(). The first argument of the function is the matrix, the second argument of the function is the result of the type double

double result; 
int fail = MatrixDet(&my_matrix, &result);

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Inverse matrix

To find the inverse matrix, use MatrixInverse(). The first argument of the function is the matrix, the second argument of the function is the matrix for the result. Returns a number other than 0 in case of a wide variety of errors.

matrix_t result;
int fail = MatrixInverse(&my_matrix, &result)

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library

I use a makefile to build projects. To build the library, use the makefile matrix.a target. He will put it in the lib directory.

jokerooo7@pc macOS % make matrix.a