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
