Matlab-Matrix - Create a Matrix

In MATLAB, you can create a matrix by entering the elements in each row as comma. You can also create a matrix with space depmited numbers and by using the semicolons to mark the end of each row.

Matrix with single row

Let us create a simple matrix in MATLAB that has a single row and three elements. Each element should have a space or comma.

Example

Consider the below mentioned elements to create a matrix.

m=[2, 4, 6]

Output

On execution in MATLAB it will display the following −

>>m = [2, 4, 6]
 
m =

   2  4  6
>>

When you execute the code in MATLAB, the result of the matrix is displayed in the command window.

Matrix with Multiple rows

Example

Let us now create a matrix with multiple rows. To do that, we need to separate each row with semicolon (;) as shown below −

m = [2 4 6; 3 6 9; 4 8 12]

Output

Here 2 4 6 is the first row, 3 6 9 is the second row and 4 8 12 is the third row. The matrix will be as follows −

m = 2  4  6
    3  6  9
    4  8 12

Let us now execute the same in MATLAB command prompt, as mentioned below −

>> m = [2 4 6; 3 6 9; 4 8 12]

m =

   2  4  6
   3  6  9
   4  8 12
   
>>

The 3x3 matrix is displayed as shown above in MATLAB.

Besides creating matrix with the values of your choice you can also make use of the built-in MATLAB functions zeros, rand or ones to create a matrix as shown below −

The zerosfunctions

This will create matrix with all zeros with the given row/column size.

Example

You can use MATLAB zeros function as follows −

m0 = zeros(3,3)

Output

You will get the following output −

>> m0 = zeros(3,3)

m0 =

   0  0  0
   0  0  0
   0  0  0
   
>>

The onesfunction

The matrix created will have ones as the values.

Example

You can use MATLAB ones function as follows −

m1 = ones(3,3)

Output

You will get the following output −

>> m1 = ones(3,3)

m1 =
   1  1  1
   1  1  1
   1  1  1
   
>>

The rand() function

The function rand() allows you to create a matrix with random elements for the size given. Here is an example for the same.

Example

m1 = rand(3,3)

Output

Let us now execute the same in MATLAB to see the results. The output is as follows −

>> m1 = rand(3,3)

m1 =

   0.8147  0.9134  0.2785
   0.9058  0.6324  0.5469
   0.1270  0.0975  0.9575
   
>>