Assigning multiple variables a single legend

I have script that plots bar charts for different sleep stages across 'trials'. I want to club one stage from each trial and assign it a color in the legend but I'm unable to do so. The script:

%% NREM

hold on;
h1=bar(categorical({'PT5',}),size(PT5_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h2=bar(categorical({'PT4',}),size(PT4_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h3=bar(categorical({'PT3',}),size(PT3_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h4=bar(categorical({'PT2',}),size(PT2_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h5=bar(categorical({'PT1',}),size(PT1_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');

%% REM


h6=bar(categorical({'PT5',}),size(PT5_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h7=bar(categorical({'PT4',}),size(PT4_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h8=bar(categorical({'PT3',}),size(PT3_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h9=bar(categorical({'PT2',}),size(PT2_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h10=bar(categorical({'PT1',}),size(PT1_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');

%% Intermediate
bar(categorical({'PT5',}),size(PT5_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT4',}),size(PT4_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT3',}),size(PT3_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT2',}),size(PT2_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT1',}),size(PT1_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');

%% Quiet Wake
bar(categorical({'PT5',}),size(PT5_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT4',}),size(PT4_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT3',}),size(PT3_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT2',}),size(PT2_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT1',}),size(PT1_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');

legend('NREM','REM','Intermediate','Quiet Wake')

ylabel('Number of Bouts');xlabel('Rest Periods')
title(strcat('threshold matrix=','[400 30 3 30]',' , ','window size=','5s',',', ' ','overlap=',num2str(0)),'Interpreter','none')

When I plot this, I get the picture shown below. I need all categories to be the color I assigned them. Thanks for helping out!

Answer 1

[Scott MacKenzie]

I suggest you re-organize your data and use a single bar function using the 'stacked' property for barlayout. Do this and it's relatively straight forward to add a legend and control the bar colors.

y1 = randi(5,1,4);
y2 = randi(5,1,4);
y3 = randi(5,1,4);
y4 = randi(5,1,4);
y = [y1' y2' y3' y4']; 

dataLabels = {'y1', 'y2', 'y3', 'y4'};

b = bar(y, 'barlayout', 'stacked');
legend(b, dataLabels, 'location', 'northeast');

b(1).FaceColor = [.8 .4 .4];
b(2).FaceColor = [.7 .9 .7];
b(3).FaceColor = [.7 .7 .8];
b(4).FaceColor = [.7 .8 .7];

[shekhar narayanan]

Yes, I think the code would be a lot simpler to understand too! Thank you so much!

Answer 2

[Walter Roberson]

%% NREM

hold on;
h1=bar(categorical({'PT5',}),size(PT5_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h2=bar(categorical({'PT4',}),size(PT4_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h3=bar(categorical({'PT3',}),size(PT3_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h4=bar(categorical({'PT2',}),size(PT2_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
h5=bar(categorical({'PT1',}),size(PT1_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');

%% REM


h6=bar(categorical({'PT5',}),size(PT5_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h7=bar(categorical({'PT4',}),size(PT4_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h8=bar(categorical({'PT3',}),size(PT3_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h9=bar(categorical({'PT2',}),size(PT2_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
h10=bar(categorical({'PT1',}),size(PT1_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');

%% Intermediate
h31 = bar(categorical({'PT5',}),size(PT5_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT4',}),size(PT4_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT3',}),size(PT3_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT2',}),size(PT2_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
bar(categorical({'PT1',}),size(PT1_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');

%% Quiet Wake
h41 = bar(categorical({'PT5',}),size(PT5_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT4',}),size(PT4_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT3',}),size(PT3_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT2',}),size(PT2_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');
bar(categorical({'PT1',}),size(PT1_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');

legend([h1, h6, h31, h41], {'NREM','REM','Intermediate','Quiet Wake'})

ylabel('Number of Bouts');xlabel('Rest Periods')
title(strcat('threshold matrix=','[400 30 3 30]',' , ','window size=','5s',',', ' ','overlap=',num2str(0)),'Interpreter','none')

[shekhar narayanan]

This did it for me! Thanks a lot!

Answer 3

[DGM]

There are a number of ways to do this, but you should just be able to pick one object from each group and use it. The trick is to pick the objects explicitly by handle instead of letting legend pick the first N objects it finds in the figure.

% ...
h1 = bar(categorical({'PT1',}),size(PT1_Changed.NREM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','b');
% ...
h2 = bar(categorical({'PT1',}),size(PT1_Changed.REM_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','r');
% ...
h3 = bar(categorical({'PT1',}),size(PT1_Changed.Intermediate_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','g');
% ...
h4 = bar(categorical({'PT1',}),size(PT1_Changed.Quiet_Wake_Bout_Wise_Firing_Rate,1),0.1,'FaceColor','y');

% explicitly specify one object from each group, use cell array of labels
legend([h1 h2 h3 h4],{'NREM','REM','Intermediate','Quiet Wake'}) 

Also, IDK if it's supposed to be that way, but the line you have assigned to h10 says NREM instead of REM

[shekhar narayanan]

Thanks for your answer! And yes, you're right it should be REM there haha. Good catch!