How can I find the surface normal of a 8 by 3 matrix?

I am attempting to find the surface normal of a 8 by 3 matrix in matlab. The matrix is

x = [0,228.6,-228.6,0,-114.3,114.3,114.3,-114.3];

y = [514.35,285.75,285.75,57.15,101.6,101.6,400.05,400.05];

z = [1873,1873,1909,1903,1909,1887,1869,1895];

Answer 1

[darova]

• Use griddata to create a surface
• Use surfnorm to find normal vectors

[nx,ny,nz] = surfnorm(x,y,z);
surf(x,y,z)
hold on
quiver3(x,y,z,nx,ny,nz)
hold off