How to store data from a nested For loop

I have the following code that generate the coordinates of a square grid using nested for loops. How can I store all coordinates in xy_coord?

xy_coord = zeros(9,2);

x = -500:500:500; % X range

y = -500:500:500; % Y range

for i=1:3

for j=1:3

xy_coord = [x(i),y(j)]

end

end

Answer 1

[Pratyush Swain]

Hi,

I beleive you can proceed in the following manner,

xy_coord = zeros(9,2);
x = -500:500:500;       % X range
y = -500:500:500;       % Y range
%keep a variable to iterate over the rows in xy_coord i.e 1-->9%
k=1;
for i=1:3
    for j=1:3     
        %store the respective x and y coordinate in that designated row%
        xy_coord(k,:) = [x(i),y(j)];
        k=k+1;
    end 
end

Hope this helps.

[Joel Olenga]

Thank you so much!

Answer 2

[Voss]

x = -500:500:500;       % X range
y = -500:500:500;       % Y range

"The" MATLAB way:

[xx,yy] = meshgrid(x,y);
xy_coord = [xx(:) yy(:)];
disp(xy_coord);

  -500  -500
  -500     0
  -500   500
     0  -500
     0     0
     0   500
   500  -500
   500     0
   500   500

Another way:

nx = numel(x);
ny = numel(y);

xy_coord = [];
for i=1:nx
    for j=1:ny
        xy_coord(end+1,:) = [x(i),y(j)];
    end
end
disp(xy_coord);

  -500  -500
  -500     0
  -500   500
     0  -500
     0     0
     0   500
   500  -500
   500     0
   500   500

Another way:

xy_coord = zeros(nx*ny,2);
count = 0;
for i=1:nx
    for j=1:ny
        count = count+1;
        xy_coord(count,:) = [x(i),y(j)];
    end
end
disp(xy_coord);

  -500  -500
  -500     0
  -500   500
     0  -500
     0     0
     0   500
   500  -500
   500     0
   500   500

Another way:

xy_coord = zeros(nx*ny,2);
for i=1:nx
    for j=1:ny
        xy_coord(j+(i-1)*ny,:) = [x(i),y(j)];
    end
end
disp(xy_coord);

  -500  -500
  -500     0
  -500   500
     0  -500
     0     0
     0   500
   500  -500
   500     0
   500   500

[Joel Olenga]

woww! I really appreciate the alternatives!