Question about for loop

I'm trying to solve this question.

A vector is given by x=[-3.5 -5 6.2 11 0 8.1 -9 0 3 -1 3 2.5]. Using conditional statement and loops, write a program that crates two vectors from x- one(P) that contains all positive elements of x, and a second(N) that contains the negative elements of x. The elements in new vectors are in the same order as in x.

I totally understand the conditional statement part, but for the loop part, I only worked this fragment out then don't know how to continue:

x=[-3.5 -5 6.2 11 0 8.1 -9 0 3 -1 3 2.5];
P=[];
N=[];
a=length(x);
for k=1:a
    if x>0

Someone please help! Thanks!

[Irfan Muhammad]

x=[-3.5 -5 6.2 11 0 8.1 -9 0 3 -1 3 2.5];

P=[];

N=[];

for k=1:length(x)

if x(k)>=0

P(k)=x(k);

else if x(k)<0

N(k+2)=x(k)

end

end

end

N=circshift(N,-2)

Answer 1

[Walter Roberson]

P(end+1) = x