How do we define the colors in the MarkerFaceColor for the plots containing lines and points?

I am plotting a graph where I have nine speakers (see the attached). I am not sure why the color of S8_M is the same as S1_F, and S9_F is the same as S2_F. This is confusing as we can't differentiate the speakers' data. May I know how to define the colors and not use the default settings? Or where am I doing wrong? Any suggestions will be appreciated. Part of the code is given below:

    ax(1)=subplot(1,2,1);
    h1 = plot(x1*100, y1, '-o'); 
    set(h1, {'MarkerFaceColor'}, get(h1,'Color')); 
    axis padded
    grid;
    xlabel('Time points (%)');
    ylabel('f0 (Hz)');
    title('beer');
    linkaxes(ax,'y')
    
   
    ax(2) =subplot(1,2,2);
    h2 = plot(x2*100, y2, '-o'); 
    set(h2, {'MarkerFaceColor'}, get(h2,'Color')); 
    title('north');
    axis padded
    grid;

Answer 1

[Voss]

Inspect either of the properties shown here:

get(0,'DefaultAxesColorOrder') % default line colors for any axes

ans = 7×3

0 0.4470 0.7410 0.8500 0.3250 0.0980 0.9290 0.6940 0.1250 0.4940 0.1840 0.5560 0.4660 0.6740 0.1880 0.3010 0.7450 0.9330 0.6350 0.0780 0.1840

figure('Visible','off');
get(gca(),'ColorOrder') % this particular axes' line colors (same as above by default)

ans = 7×3

0 0.4470 0.7410 0.8500 0.3250 0.0980 0.9290 0.6940 0.1250 0.4940 0.1840 0.5560 0.4660 0.6740 0.1880 0.3010 0.7450 0.9330 0.6350 0.0780 0.1840

You see there are 7 colors defined (7 rows of RGB values). MATLAB cycles through these colors when you use plot and other high-level plotting functions. Since there are 7 colors there and you plot 9 lines, the last two lines get the same colors as the first two, as you observe.

There are different ways to go about changing this. One way is to change one or both of the above settings:

% add grey and black to the default set of colors for any axes:
default_colors = get(0,'DefaultAxesColorOrder');
set(0,'DefaultAxesColorOrder',[default_colors; 0.5 0.5 0.5; 0 0 0]);

% or add grey and black to the set of colors for this axes only:
default_colors = get(gca(),'ColorOrder');
set(gca(),'ColorOrder',[default_colors; 0.5 0.5 0.5; 0 0 0]);

Then use plot like before:

set(gcf(),'Visible','on');
for ii = 1:9
    plot(1:10,-ii+(1:10)); % using color order with 9 colors now, last two are grey and black
    hold on
end
legend();

Or you can explicitly specify each color when you plot, without changing those settings:

figure();
colors = rand(12,3); % 12 random colors, you can specify the colors you want here
for ii = 1:size(colors,1)
    plot(1:10,-ii+(1:10),'Color',colors(ii,:));
    hold on
end
legend();

[Anu]

Thanks @_ for the prompt reply and the insights. Now I understood why the colors are the same. This solves the problem partially (see the attached).

    ax(1)=subplot(1,2,1);
    h1 = plot(x1*100, y1, '-o'); 
    %set(h1, {'MarkerFaceColor'}, get(h1,'Color')); 
    default_colors = get(gca(),'ColorOrder');
    set(gca(),'ColorOrder',[default_colors; 0.5 0.5 0.5; 0 0 0]);
    axis padded
    grid;
    xlabel('Time points (%)');
    ylabel('f0 (Hz)');
    title('beer');
    linkaxes(ax,'y')
    
   
    ax(2) =subplot(1,2,2);
    h2 = plot(x2*100, y2, '-o'); 
    %set(h2, {'MarkerFaceColor'}, get(h2,'Color')); 
    default_colors = get(gca(),'ColorOrder');
    set(gca(),'ColorOrder',[default_colors; 0.5 0.5 0.5; 0 0 0]);
    title('north');
    axis padded
    grid;

However, I think the ColorOrder does not work with the MarkerFaceColor. I need to show the plots with filled points. If I need to fill it with a red color, I could have specified it in the plot function.

 h1 = plot(x1*100, y1, '-o', 'MarkerFaceColor','r'); 

But, I need to fill the points with the same colors as the lines. I don't know how to fix this. Any suggestion?

[Voss]

Since you are letting the ColorOrder determine the colors of the lines, then you still have to set the MarkerFaceColor of the lines explicitly, like you were doing before (because by default MarkerFaceColor is 'none', i.e., no fill).

The only difference now is that there will be enough colors in the ColorOrder so that you don't get repeated colors.

    ax(1)=subplot(1,2,1);
    
    default_colors = get(gca(),'ColorOrder');
    % gonna use the same set for both axes, so store it:
    default_colors = [default_colors; 0.5 0.5 0.5; 0 0 0];
    set(gca(),'ColorOrder',default_colors);
    
    h1 = plot(x1*100, y1, '-o'); 
    set(h1, {'MarkerFaceColor'}, get(h1,'Color')); 
    axis padded
    grid;
    xlabel('Time points (%)');
    ylabel('f0 (Hz)');
    title('beer');
    linkaxes(ax,'y')
    
   
    ax(2) =subplot(1,2,2);
    
    set(ax(2),'ColorOrder',default_colors);
    
    h2 = plot(x2*100, y2, '-o'); 
    set(h2, {'MarkerFaceColor'}, get(h2,'Color')); 
    title('north');
    axis padded
    grid;

[Anu]

Ohh makes sense! Thanks. It works perfectly.

    ax(1)=subplot(1,2,1);
    
    default_colors = get(gca(),'ColorOrder');
    default_colors = [default_colors; 0.5 0.5 0.5; 0 0 0];
    set(gca(),'ColorOrder',default_colors);
    
    h1 = plot(x1*100, y1, '-o'); 
    set(ax(1),'ColorOrder',default_colors);
    set(h1, {'MarkerFaceColor'}, get(h1,'Color'));
    axis padded
    grid;
    xlabel('Time points (%)');
    ylabel('f0 (Hz)');
    title('beer');
    linkaxes(ax,'y')
    
    ax(2) =subplot(1,2,2);
    h2 = plot(x2*100, y2, '-o');
    set(ax(2),'ColorOrder',default_colors);
    set(h2, {'MarkerFaceColor'}, get(h2,'Color')); 
    title('north');
    axis padded
    grid;

[Voss]

Excellent! You're welcome!