I need help with for loops

I am new to matlab and I'm writing a for loop that will answer eather true or false whether a number in a vector is positive or negative. ie A = [-5 -3 2 37 -33 6] and answer B = [false false true true false true]. Any advice you may be able to give me?

[Omik Save]

for i = 1:length(A)
    if A(i) > 0
        B(i) = 'true';
%     elseif A(i) == 0
%         B(i) = 'zero';
    else
        B(i) = 'false';
    end
end

[Mark Woolsey]

Thank you for your responce, but that did not work

Here is what I have

clc, clear

A = [-100 20 50 -2 -55 3 40 -27];

for i = 1:length(A);

if A(i) > 0

B(i) = 'true'

else

B(i) = 'false'

end

end

[David Hill]

Why do you need to use a loop?

B=A>=0;%logical array (why do you need 'true' and 'false'?) you will have to do either a string array or cell array
l=["false","true"];
C=l((A>=0)+1);%string array
h={'false','true'};
D=h((A>=0)+1);%cell array

[Mark Woolsey]

It is an asignment that I need to use a for or while loop to answer the question.

Answer 1

[Prasad Reddy]

clc
clear all
A = [-100 20 50 -2 -55 3 40 -27]
B=zeros(1,length(A))
for i = 1:length(A)
    if A(i) > 0
        B(i) = true
    else
        B(i) = false
    end
end
% This will work. but you will get 1 in place of true and 0 in place of false.
% please give upthumb if this works well.
% i am trying more specifically for your code. 
% will update soon once got the answer.

Answer 2

[Prasad Reddy]

clc
clear all
A = [-100 20 50 -2 -55 3 40 -27]
for i = 1:length(A)
    if A(i) > 0
        B(i) = {'true'};
    else
        B(i) = {'false'};
    end
end
B
% This is the final Answer. 
% Hear you are trying to crete a string array B, which will have true and false. 
% I think this is the only way in which you can do it. 
% please provide up thumb if it works. Iworked for this problem for an hour.

[Mark Woolsey]

This will work if i remove the (' ') around the true false statements, but i get the answer with 0's and 1's. Is there a way to convert the 0's and 1's to true and false outside the loop?

If i leave this in (' '), I get this responce:

In an assignment A(:) = B, the number of elements in A and B must be the same.