Contour plot along predefined surface

Hi,

I have 3D-data, with Z = f(x,y) in numerical format consistent with meshgrid.

I would like to make a contourplot of this surface along a given plane, which is not parallel to the Z-axis. I also want to get the X,Y-values of the intersection of this inclined plane and the surface Z in a matrix as output.

To get the idea, it's basically the same as the function C = contourc(x,y,Z,v) does, but contourc can apparently only handle elevations parallel with the Z-plane.

Of course, I can just rotate all the data so that its new Z-axis is perpendicular to the surface I wish to make the contour projections on (that's quite easy), but it seems too high computational effort.

Any help is appreciated.

[Bruno Luong]

"Of course, I can just rotate all the data so that its new Z-axis is perpendicular to the surface I wish to make the contour projections on (that's quite easy), but it seems too high computational effort."

You don't need to rotate the (x,y,z), just substract by the plane equation (a**x+b*y)

zz = z - (a*x+b*y)

do the concour on zz, call it

zz(xx,yy) = cst value

then recover

z = cst + a*xx + b*yy

Answer 1

[Scott Booth]

You could loop through the data to collect the points of intersection and then graph them with the plot3 command.