Creating a 365x24 matrix using for and if

Hi!

I'm trying to create a numeric matrix. Every row is a day of the year and every collumn is an hour of the day, so the matrix's size is going to be 365x24.

i need all the sells to have the same value (-9999) and I need to to this using a loop in order to save time.

Here's what I've typed so far.

COSMY2014=zeros(size(COSMY2013));
i=1;
j=1;
for i < 366 
    for j < 25
        if COSMY2014(i,j)=0
            COSMY2014(i,j)=-9999;
        end
         j=j+1;
    end
    i=i+1;
end

I have created a matrix with the correct size but every cell's value is 0. What I'm trying to do in this piece of code is change every value to -9999 but when I run it nothing happens. I cannot find errors in the logic so I assume I've made mistakes in the syntax.

I really appreciate any help you can give me!

[Stephen23]

Assuming that COSMY2013 has the same size:

COSMY2014 = COSMY2013;
COSMY2014(:) = -9999

Answer 1

[Rik]

You're confusing while and for.

But you need neither:

COSMY2014=-9999*ones(365,24);

[Fe Mav]

Thank you very much for the quick answer and the smart solution!