How can you extend a vector with the last value?

Hi,

I have two vectors with different dimensions. Vector X is 1x5, the other vector A has the dimension 1x3.

Now I want to plot(X,A), but because of the different dimensions of the vectors this obviously doesn't work.

A solution that would work for me is to take the last value of A and extend the vector to a 1x5 format so that the 4th and 5th value is the same as the last value (in this case the 3rd).

So it should look something like

A = ( 1 A_new = (1

2 ---> 2

3) 3

3

3)

This is only supposed to serve as an example, in my real problem the dimensions are like 1x92000. That's why putting in the values by hand would be very time-consuming.

I would love some help for this question, thanks in advance!

[Bruno Luong]

Instead of extend with last value, which is an emperical extension, why not fill with NaN, so that the non-exsiating data is not plotted

X = 1:10;
A = rand(1,5);

A_pad = A;
A_pad(end+1:length(X)) = NaN;

plot(X, A_pad)

Answer 1

[VBBV]

X = rand(1,5)

X = 1×5

0.3283 0.7485 0.9979 0.2897 0.8934

A = rand(1,3) 

A = 1×3

0.9032 0.1387 0.2475

Anew = [A repmat(A(end),1,size(X,2)-size(A,2))]

Anew = 1×5

0.9032 0.1387 0.2475 0.2475 0.2475