How do I plot a transparent contour and its colour?

Hello,

I have the following contour map with 3 zones from 3 sets of contour data, set to show just a single level, generated by the following code:

contourf(X,Y,ContourData1,[0.2,0.2],'LineWidth',2)

hold on

contourf(X,Y,ContourData2,[0.15,0.15],'LineWidth',2)

hold on

contourf(X,Y,ContourData3,[0.1,0.1],'LineWidth',2)

How do I make the coloured regions transparent, as well as change their colours? Currently the colours are default for the levels that each contour displays. I want something that looks like this:

Thanks

Answer 1

[Alan Stevens]

Possibly by assigning a handle like so:

h = contourf(X,Y,ContourData1,[0.2,0.2],'LineWidth',2);

then setting

h.CurrentObject.FaceAlpha = 0.2;

where you can replace 0.2 with a number between 0 and 1 until you get the degree of transparency you want.

I've not tested this on your figure as I don't have access to ContourData1, 2 and 3.

[Hamid Attar]

It doesn't work.

Please assume ContourData 1 2 3 are from the Peaks function, or some other readily available built-in matlab function for testing.

And what about the colours?

[Alan Stevens]

Hmm. I used the patch function in my test. It looks like contourf doesn't have transparency control (other than on or off).