My code is keep plotting the wrong data

I have a 9 coloumns by 150 rows matrix and I have chosen three coloumns from it to form my new 3 comloumns matrix, so I chose second to be my Z (hight) and 8 and 9 to be my x and y respectively.

M = TEST(:,[8;9;2])

surfl(M)

So, now I have a 3x150 Matrix and idealy it is 3 coloumns where first is X, second is Y and third is Z. Whenever I use surf. comand it plots wrong data and I am sure when I pick a plotted point it is all wrong. I do not know what to do to fix it.

and I do not want to plot a mathematical function I already have X Y and Z, and when I separate them, the code gives me an error that Z must be a matrix not vector, while it is obviously a matrix. I do not know how to solve it.

Answer 1

[Star Strider]

Perhaps —

TEST = randn(150,9);
 M = TEST(:,[8 9 2]);
x = M(:,1);
y = M(:,2);
z = M(:,3);
L = size(M,1);
xv = linspace(min(x), max(x), L);
yv = linspace(min(y), max(y), L);
[Xm,Ym] = ndgrid(xv, yv);
Zm = griddata(x,y,z,Xm,Ym);

figure
surf(Xm, Ym, Zm)
grid on
xlabel('X')
ylabel('Y')
zlabel('Z')

This should work with your data. It would help to have it to be certain.

.

[Peter]

It worked Thank you so much :)

[Star Strider]

My pleasure!

If my Answer helped you solve your problem, please Accept it!

.

Answer 2

[Jonas]

may the scatter3() command is suffiecient to visualize your data, you interpolate (e.g. interp3) your XYZ data to generate more points and use surf() after that