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Matrix - linear algebra library for C++

This project is similar to the project on C (link) but with couple differences.
Here we have better user experience because of the Object-Orientation of C++.

Installation

macOS

git clone https://github.com/georghegel/matrix_cpp.git
cd matrix_cpp
make

For test:

make test

Linux

Similar to macOS:

git clone https://github.com/georghegel/matrix_cpp.git
cd matrix_cpp
make

For test:

not ready yet

How to use

Arithmetic operations

Addition/Subtraction

S21Matrix m1(3,3);
S21Matrix m2(3,3);

m1(0,0) = 1;
m1(0,1) = 2;
m1(0,2) = 3;
m1(1,0) = 4;
m1(1,1) = 5;
m1(1,2) = 6;
m1(2,0) = 7;
m1(2,1) = 8;
m1(2,2) = 9;

// let's say m2 fills in the same way
m1.SumMatrix(m2);

Let's print the result (it's located in m1):

m1.print();
//  2   4   6
//  8   10  12
//  14  16  18

Multiply by number

Element-wise multiplication by a given number:

S21Matrix m1(3,3); // just take the matrix from the previous example

double number = -3.0;
m1.MulNumber(number);

m1.print();
//  -3  -6  -9
//  -12 -15 -18
//  -21 -24 -27

Matrix multiplication

Here is the link how does it work:

S21Matrix m1(3,3); // as in the previous example
S21Matrix m2(3,3);

m2(0,0) = 0.7;
m2(0,1) = 11;
m2(0,2) = 0.3;
m2(1,0) = 11;
m2(1,1) = 2;
m2(1,2) = 1;
m2(2,0) = 0.5;
m2(2,1) = 3;
m2(2,2) = -1;

m1.MulMatrix(m2);

m1.print();

//  24.2    24    -0.7
//  60.8    72     0.2
//  97.4    120    1.1

Determinant

How to calculate determinant in Wiki:

S21Matrix m1(2,2);

m1(0,0) = 1;
m1(0,1) = 2;
m1(1,0) = 3;
m1(1,1) = 4;

double det = m1.Determinant();
std::cout << "Determinant is equal to " << det << std::endl;
//  Determinant is equal to -2

Inverse Matrix

About inverse matrix on Wiki:

S21Matrix m1(3,3);
S21Matrix inverse(3,3); // where will live our inverse matrix
m1(0,0) = 1;
m1(0,1) = 2;
m1(0,2) = 13;
m1(1,0) = 4;
m1(1,1) = 51;
m1(1,2) = 6;
m1(2,0) = 17;
m1(2,1) = 8;
m1(2,2) = 2;

inverse = m1.InverseMatrix();
inverse.print();

//  -54/10613   -100/10613    651/10613
//  -94/10613    219/10613    -46/10613
//  835/10613    -26/10613    -43/10613

Conjugate Matrix

S21Matrix m1(3,3);
S21Matrix res(3,3);
m1(0,0) = 1;
m1(0,1) = 2;
m1(0,2) = 3;
m1(1,0) = 0;
m1(1,1) = 4;
m1(1,2) = 2;
m1(2,0) = 5;
m1(2,1) = 2;
m1(2,2) = 1;

res = m1.CalcComplements();
res.print();

//   0   10  -20
//   4  -14    8
//  -8   -2    4

Some other useful functions:

Method signature	Description
void Resize(int rows, int cols)	resizes matrix to the given rows and columns
void print()	prints matrix
S21Matrix transpose()	transposes initial matrix and returns new, transposed one
bool EqMatrix(const S21Matrix& other)	returns true, if matrices are equal. otherwise 0