# how can I take the (x,y) coordinates of each point by having two different vectors for x and y respectively?

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Ang Vas on 28 Jul 2015
Commented: Ang Vas on 29 Jul 2015
Lets say that I have a matrix T=[1 2 1 2 3;1 2 4 1 2;0 2 1 3 4;2 1 0 3 1] I used the below code in order to have a plot
figure, axis([0 10 0 10]);
grid on; hold on;
[m,n] = size(T);
m = m*2 - 0.5;
n = n*2 - 0.5;
for i = 1:size(T,1)
I = (i-1)*2;
for j = 1:size(T,2)
J = (j-1)*2 + 0.5;
if(T(i,j)>0)
plot(J,m-I,'b.','MarkerFaceColor', 'b');
end
if(T(i,j)>1)
plot(J+1,m-I-1,'b.','MarkerFaceColor', 'b');
end
if(T(i,j)>2)
plot(J+1,m-I,'b.','MarkerFaceColor', 'b');
end
if(T(i,j)>3)
plot(J,m-I-1,'b.','MarkerFaceColor', 'b');
end
end
end
how can I take the (x,y) coordinates of each point from the plot by having two different vectors for x and y respectively?

Guillaume on 28 Jul 2015
With code like this you need to write a comment explaining what's going on: what the different values of T mean and how the point coordinates are calculated. You may know now what it is but when you revisit the code in a few months you'll have forgotten. And it helps anybody else understand what is going on.
One possible way to build your coordinate array:
[rows, cols] = size(T);
[basex, basey] = meshgrid(0.5:2:2*cols,rows*2-0.5:-2:0.5);
%when T > 0, use basex, basey
%when T > 1, also use basex+1, basey-1
%when T > 2, also use basex+1, basey
%when T > 3, also use basex, basey-1
x = [basex(T>0); basex(T>1)+1; basex(T>2)+1; basex(T>3)];
y = [basey(T>0); basey(T>1)-1; basey(T>2); basey(T>3)-1];
figure, axis([0 10 0 10]);
grid on; hold on;
plot(x, y, 'b.','MarkerFaceColor', 'b');
Ang Vas on 29 Jul 2015
Thank you a lot for your help!