I have an index vector that I have to change and I want to change the values of them

Hi all!

I have a vector:

 v = [1 0 0 1 1]

I got another index vector that says me which of these values have to be changed to 1:

 index = [1 5 3]

The result should be:

 v = [1 0 1 0 1]

The code to do this with a for is this one:

 for i=1:Nc_needed 
    v(index(i)) = 1;
 end

I know that there are ways to do it in only one line. Anyone knows how?

Answer 1

[Wayne King]

   v = [1 0 0 1 1];
   idx = [1 5 3];
   v(idx) = 1;

But that does not give exactly what you said originally because orignally, elements 1,4,and 5 were already ones, so all the above does is set element 3 to a 1.

Another way

   v = zeros(1,5);
   v(idx) = 1;

So the way to do it with one line is create a vector of indices that you want to change -- the indices must be greater than or equal to 1 and less than or equal to the length of the vector, then use that vector to assign the value to "data" vector

[Dani Tormo]

What a quick response! The second is what I was looking for.

Many thanks!