How to delete some elements from a vector in Matlab and Octave

To delete an element from a vector, assign a null value [ ] to the element

v(n)=[ ]

The parameter n is the position of the element in the index of the vector.

To delete some continuous elements in the index write this comand

v(x:y)=[ ]

The x parameter is the position of the first element of the range, the y parameter is the position of the last element of the range.

To delete all elements of a vector, assign a null value [ ] to the vector

v=[ ]

This command deletes the elements present in the vector

Examples

Define a vector

>> v=['a'; 'b'; 'c'; 'd'; 'e'; 'f';'g']
v =
a
b
c
d
e
f
g

The vector has seven elements

To delete the sixth element, type

v(6)=[ ]

Now the vector has six elements

v =

b
c
d
e
g

To delete the group of elements between the second and fourth element type

>> v(4:6)=[ ]

Now the vector has 3 elements.

v =
a
b
c

To delete all elements of the vector type

>> v=[ ]

This command deletes all elements in the vector.