MATLAB: Add an integer x to certain values of a vector

addelementvector

for example i have the number 8, and i have a vector[ 1 2 3 4 5]

i need to add 8 to the elements 1-4 of the vector to get the value 18

how would i do this?

8 + sum(YourVector(1:4))

temp = reshape(vector_1, 4, []);
temp = [temp; temp(1:2,:)];
Vector_2 = reshape(temp, 1, []);

Possibly:

rank = [4, 1, 2, 2, 4];
[~, ~, rank_new] = unique(rank)