Contour lines over contourf 2D matrix

I would like to plot thick lines where y = n as a contour line on top of a contourf plot (like the image attached). How can I do this?

I have 3 Matrices I use to contourf: xi,yi,zi - all same dimensions (200x100). I want to use zi data to create the superimposed contours. I do not wish to set the levels within contourf as this is not useful for what I wish to do. I would like to control the contours completely seperate.

For an extra bonus point, it will be nice to have corresponding labels.

Answer 1

[Star Strider]

Use the hold function, and plot only the lines of interest using a second call to the contour (not contourf) function.

See the contour documentation for Display Single Contour Line for details.

[Michael]

Thanks! works perfectly.

I was stupid and left in the 'LineStyle','none' when trying this before so I thought it wasn't possible this way...

[Star Strider]

My pleasure!

Not stupid — just an experiment that didn’t work out as you wanted. That’s how we learn!