Shaded plot on a parametric surface (cylinder)

Hello everyone! I have measured the magnetic field around the outside of a cylinder, at a constant radius. I am using MATLAB to process the data and have created 2D imagesc plots of the field intensity as a function of the axial and angular position. I would like to plot this data on the surface of a cylinder that represents the cylindrical surface that I am measuring on, how would I achieve this?

Example data: Z = 40x1 double from 0 to 1m

angle = 18x1 double from 0 to 2pi

Field = 18x40 double

Graph in 2D:

I now want to visualise this in 3D on the surface of a cylinder at constant R.

Thanks for your help!

Answer 1

[John D'Errico]

You plotted an array in terms of cylindrical coordinates, where one of the axis variables was angle. Convert that angle to cartesian coordinates. If you don't know how to do that, at the least you can use pol2cart as long as you know the radius.

help pol2cart

This will give you xyz coordinates for that surface. now surf will do nicely, or you can use patch.

help patch

Answer 2

[Rollo]

Thanks John, I knew it would be something simple, I'll give this a go

[John D'Errico]

I recall you will want to use a form like

surf(X,Y,Z,C)

where C is the mapping you use to determine the colors on that surface. X and Y come from the polar conversion of course. And if your cylinder is at some more general angle, then this is still only a linear transformation of X,Y,Z.