Plot two set of curves with the same colours on the same figure

I have two sets of curves plotted with a loop:

for ....
        plot(den_avg,(z),'-','LineWidth',2) %Set 1
    hold on
    plot(velu_avg+1,(z),'--','LineWidth',2) %Set 2
    hold on
end

I basically want sets 1 and 2 to have the same colours, this is:

First iteration: Plot 1 blue colour, Plot 2 blue colour

Second iteration: Plot 1 red colour, Plot 2 red colour

etc

How to do this?

Answer 1

[Ishaan Mehta]

Hi Carlos

I understand that you want to plot two curves on the same figure, and wish to change the plot color for each iteration of the for loop.

You can use MATLAB's rand function to create a random integer during each iteration, and use this random value to specify the color.

Here is a code snippet for the same:

t = 0:0.01:8;
colors = ["red", "blue", "green", "cyan", "magenta", "yellow", "black"];
numel(colors)

ans = 7

for i = 1:10
    plotColor = colors(rem(i, numel(colors)) +1);
    
    hold on
    % printing sin and cos waveforms for demo
    plot(t, sin(t + (0.2 * i)), 'color', plotColor); 
    plot(t, cos(t + (0.2 * i)), 'color', plotColor);
    hold off
end

Hope it helps

Ishaan Mehta

[carlos g]

Hi Ishaan,

Is it possible to replace randomColor by the actual by-default MATLAB colours? Namely blue, red, etc

[Ishaan Mehta]

Hey Carlos

Yes, that's possible too. I have updated my answer to use color codes for red, blue etc., please have a look.

You can also take a look at Specify Plot Colors documentation page for more color options.

Ishaan