Create two arrays on the basis of other arrays

Given

SP = [1 2 4 6 7 9 10]
V = [5 20 10 15 5 20 10 ]

I want to obtain the two following two arrays

A = [1 1 1 1 1 4 4 4 4 4 4 4 4 4 4 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 10 10 10 10 10 10 10 10 10 10]
B= [2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 7 7 7 7 7 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 ]

That is, starting from 1, I position one in the first vector A as many times as is indicated in V. then I switch to 2 and position it in B as many times as is indicated in V. Then I take 4 and put in the vector (A or B) that is less empty, so A. then again with 6, I put it in A again becuase its length is less then the one of B and so on with the other elements till obtaing the final vector A and B

[Star Strider]

Duplicate: Create a sequence that take into account two arrays

[luca]

No they are two different things Star. I'm trying to following different ways to apporach the problem

Answer 1

[Guillaume]

%first find which of A or B elements are going into. Only depends on V
isA = false(size(V));  %put in A (true) or B (false)
lA = 0; lB = 0;  %current length of A and B
for vi = 1:numel(V)
    if lA <= lB %put in A
        lA = lA + V(vi);
        isA(vi) = true;
    else  %put in B
        lB = lB + V(vi);
    end
end
A = repelem(SP(isA), V(isA))
B = repelem(SP(~isA), V(~isA))

[luca]

it gives me error and I don't know why

[luca]

 isa(vi) = true;

is

  isA(vi) = true;
  

?

[Guillaume]

Indeed. FIxed that and another mistake.

[luca]

is there another mistake?

[luca]

oh yes, SP . Thanks Guillaume