save data in for loops

Hi everyone,

I am trying to save my data into a matrix, each time two columns as X and Y.

but the codes don't work.

Can anyone explain and help?

Thanks a lot.

coordinate= zeros();


for a=1:21
Z=[X Y];
X = snakes{1,a}.x;
Y = snakes{1,a}.y;

coordinate((a),:)= Z;

end

[Ajay Kumar]

what is X?

what is Y?

why are you assigning X and Y to Z and declaring them after assigning?

what is snakes?

what is x?

what is y?

[Stephen23]

yunwei hu's "Answer" moved here:

Hi there,

x, y and snakes are just data l got from somewhere else and need to evaluate.

the question here is how to get X an Y into two columns of a new matrix.

[Ajay Kumar]

what is the format of those?

Could you upload x, y and snakes here.

[yunwei hu]

i uploaded the snakes.

x and y are all inside of it.

Answer 1

[Ajay Kumar]

Yes, You are trying to assign 2 matrices of different size. Try this:

coordinate= zeros(41,1);
for a=1:21
    X = snakes{1,a}.x;
    Y = snakes{1,a}.y;
    % Z=[X Y];
    if a == 1
        coordinate(:,end)= X;
        coordinate(:,end+1) = Y;
    else
        coordinate(:,end+1)= X;
        coordinate(:,end+1) = Y;
    end
end

coordinate size will be 41x42. For each a, we have 41x2 which means for 21 a's it will be 41x42.