MatrixLib

MatrixLib is a c# library that helps you to create matrices and do matrix calculations in c#. It is very simple to use.

How to add

You need to download the dll , or you can build the dll from the source code.

• Create a project
• Open solution explorer menu
• Right click on references and click Add Reference -
• Click Browse
• Select MatrixLib.dll and click Add
• We have successfully added the library .
• Don't forget the include the library.
• 
• Now we are ready to use the library

Create matrix

There are different ways to create matrix , but one of them is

Empty matrix creation

Matrix matrix = new Matrix(3,3);

We specified the row length and column length of the matrix. After doing that we can add rows and columns. Adding rows and columns will be explained later.

Matlab like matrix creation

   Matrix matrix = new Matrix("[12 6 3;15 56 88;55 32 18]");

Created matrix will look like:

You have to type ';' semicolon after row. You have to type space after element. Typing unnecessary spaces causes error.

If the string is not in desired format this will throw MatrixFormatException You can catch it :)

Create matrix from two dimensional double array

   double[,] twoDimensionalArr = new double[2, 2] {
    {80,9 },
    {16,71 }
    };
    Matrix matrix = new Matrix(twoDimensionalArr);
    

Created matrix will look like:

Adding rows and columns

There are 2 functions to adding rows and columns;

Adding as rows AddAssRow(int index, double [] arr)

   Matrix matrix = new Matrix(3,3);
   double[] row1 = { 1, 6, 6 };
   double[] row2 = { 5, 7, 3 };
   double[] row3 = { 3, 4, 8 };
   matrix.AddAsRow(1 , row1);
   matrix.AddAsRow(2 , row2);
   matrix.AddAsRow(3 , row3)
    

Matrix will look like:

Adding as columns AddAssColumn(int index, double [] arr)

 Matrix matrix = new Matrix(3,3);
 double[] col1 = { 7, 4, 1 };
 double[] col2 = { 4, 5, 7 };
 double[] col3 = { 9, 8, 6 };
 matrix.AddAsColumn(1 , col1);
 matrix.AddAsColumn(2 , col2);
 matrix.AddAsColumn(3,  col3);
    

Matrix will look like:

Matrix row length and column length

You may want to get row length and column length of the matrix. There are two properties for that;

Matrix matrix = new Matrix("[12 6 3;15 56 88;55 32 18]");
Console.WriteLine("Row length of the matrix is = " + matrix.RowLength);
Console.WriteLine("Column length of the matrix is = " + matrix.ColLength);  

Output is :

Displaying matrices

There are ToString() method to display matrices.

Matrix matrix = new Matrix("[12 6 3;15 56 88;55 32 18]");
Console.WriteLine(matrix.ToString());

Output is:

Getting and setting matrix elements

We can get and set matrix elements by using indexer.

Getting matrix element

Matrix matrix = new Matrix("[12 6 3;15 56 88;55 32 18]");
Console.WriteLine(matrix[1,1]);
// this will output the first row and first column element (12)

Setting matrix element

Matrix matrix = new Matrix("[12 6 3;15 56 88;55 32 18]");
matrix[2, 3] = 42;
 //this will change the second row and third column element to (42)

Matrix addition , subtraction and multiplication

You can simply add or subtract matrices like int or double.

Addition

Matrix m1 = new Matrix("[12 6 3;15 56 88;55 32 18]");
 Matrix m2 = new Matrix("[8 5 4;12 55 12;43 18 12]");
Matrix m3 = m2 + m1;
Console.WriteLine(m3.ToString());

if the row and column lengths of the matrices are not equal this will throw MatrixAdditionException

Output is:

Subtraction

Matrix m1 = new Matrix("[12 6 3;15 56 88;55 32 18]");
Matrix m2 = new Matrix("[8 5 4;12 55 12;43 18 12]");
Matrix m3 = m2 - m1;
Console.WriteLine(m3.ToString());

if the row and column lengths of the matrices are not equal this will throw MatrixSubtractionException Output is:

Multiplication

Matrix m1 = new Matrix("[1 2;2 0;3 1]");
Matrix m2 = new Matrix("[4 3;1 2]");
Matrix m3 = m1* m2;
Console.WriteLine(m3.ToString());

if the number of columns of the first matrix is ​​not equal to the number of rows of the second matrix this will throw MatrixMultiplicationException Output is :

Multiplication matrix with scalar number

   Matrix m1 = new Matrix("[1 2;2 0;3 1]");
   Matrix m3 = m1* 2;
   Console.WriteLine(m3.ToString());

Output is:

Transpose of the matrix

You can easily get the transpose of the matrix using Transpose(); method.

   Matrix m1 = new Matrix("[2 6 7;3 6 2;4 6 5]");
   Matrix m2 = m1.Transpose();
   Console.WriteLine(m2.ToString());

Output is :

Determinant of the matrix

There is Det(); method for calculate determinant.

   Matrix m1 = new Matrix("[1 5 3;2 4 7;4 6 2]");          
   Console.WriteLine(m1.Det());
   // output is (74)

If matrix is not square this will throw MatrixIsNotSquareException

Turning matrix into two dimensional double array

   Matrix m1 = new Matrix("[1 5 3;2 4 7;4 6 2]");
   double[,] arr = m1.ToDoubleArray();
   

Contributors

• Emir Yusuf Topbaş [email protected]

License & copyright

Licensed under the MIT License