How to get this kind of plot

I have 3d discrete dataset where for every independent variable x and y there is a frequency value z.

I want to plot it like the chart below:

How do i do this?

Thanks

[per isakson]

Hint:

    imagesc( magic(12) )

[Edward]

Thankyou! is there anyway i can change the 0 color to something other than blue?

Answer 1

[per isakson]

It requires a bit of code to make this plot.

• select a suitable colormap (You might have to define your own. See colormapeditor.) Let ix=1 be white.
• map the frequences to the colormap-indicies, e.g [1:64] (should have been [2:64]). Assign 1 to missing values or whatever white means.
• use image - not imagesc
• fix the axes ticklabels

or better(?)

• select the colormap of your choice and add an extra row for the "missing-value-color"
• map frequency to the "colormap" and missing-value to the "extra row".
• the colorbar ticklabels will require some extra work

I use the approach described above. Pro: I get full control of the colors and the resulting code is fast. Con: requires some coding and testing.

pcolor might offer a simpler way. Try

    x = [1:8];
    y = [1:8];
    z = x' * y ;
    z(4:5,7) = nan;
    pcolor( x, y, z )

Note, this gives a plot with 7x7 squares.

[per isakson]

I updated the answer

[Edward]

Thanks for the help, Ive accepted your answer!