vectorB(n) = sum(vectorA(1:n)) without a loop

I would like to do:

vectorB(n) = sum(vectorA(1:n)) 

without a loop.

Thanks in advance

Answer 1

[madhan ravi]

Perhaps you just want cumsum()

help cumsum
doc cumsum

Or you just need:

v= accumarray(n(:),n(:),[],@(x) sum(vectorA(1:x)));
Wanted = v(n);
% or
Wanted = arrayfun(@(x) sum(vectorA(1:x)),n)

[Christian Tieber]

cumsum looks good.

Thanks!