How would I write this code using for and while loops/

[James Tursa]

What have you done so far? What specific problems are you having with your code?

[Olivia Gilliam]

How do I flip every entry for V?

[David Hill]

You could use if statement

for i=1:length(V)
    if V(i)
        V(i)=0;
    else
        V(i)=1;
    end
end

[Olivia Gilliam]

Yeah I finally figured out 2a of the problem. Im working on 2b, so I'm trying to flip every second instance of 0. If I do it right, array V (V = [1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1]), should become V = [1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1]. I underlined the zeroes that should flip to ones.

This is the code I used:

But, instead of getting V = [1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1]

I get:

Any help?

Answer 1

[Sourabh Kondapaka]

Hi @Olivia Gilliam,

I would recommend you to check out the free Matlab OnRamp Course

For 2b:

V = [1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1];

count = 0;
for i = 1 : length(V)
    % Below 'if' condition is same as :  if V(i) == 0
    if ~V(i)
        count = count + 1;
        
        % As you want to modify every second instance, i'm just checking the modulus value of count 
        % with 2.
        
        if mod(count,2) == 0
            V(i) = 1;
        end
    end
end