The figure can be created with several colors greater than the default number of colors by resetting the property "DefaultAxesColorOrder" of the figure.
As an example, this can be done with the following code snippet:
h = colormap(lines);
close(gcf)
set(0,'DefaultAxesColorOrder',h);
plot(rand(20,20))
Alternatively, you could also define your own colormaps by specifying RGB values for the variable "h" in the above example.
