Matlab-Matrix – Deletion of Row & Column

You can delete an entire row or column of a matrix by assigning an empty set of square braces [] to that row or column. Basically, [] denotes an empty array.

Example

For example, let us delete the fourth row of a, as shown below −

a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8];
a( 4 , : ) = []

Output

Here is the execution of above code in MATLAB

>> a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8]
a( 4 , : ) = []

a =

   1  2  3  4  5
   2  3  4  5  6
   3  4  5  6  7
   4  5  6  7  8
 
a =

   1  2  3  4  5
   2  3  4  5  6
   3  4  5  6  7
 
>>

The fourth row is deleted. It displays only three rows.

Example

Next, let us delete the fifth column of a, as shown below −

a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8]
a(: , 5)=[]

Output

Let us see the execution of the above code in MATLAB −

>> a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8]
a(: , 5)=[]

a =

   1  2  3  4  5
   2  3  4  5  6
   3  4  5  6  7
   4  5  6  7  8
 
a =

   1  2  3  4
   2  3  4  5
   3  4  5  6
   4  5  6  7
 
>>