How could I set the legend for a particular bar in a bar chart?

I have a bar chart describing 22 groups of data (from the year 1997 to 2018), each group has 10 elements (see the below fig), now I want to set a legend for the 7th bar of year 2004 (a purple bar), how could I do that? Thanks a lot..

[darova]

Can you please attach your script and data?

[Artur Zych]

How did you get the bar of year 2004 to be a purple?

Because I can only get a series to one color

Answer 1

[Adam Danz]

Assign a name to the "DisplayName" propery of each grouped bar handle. The display name will be used in the legend. Here's an example below.

% This will produce 4 groups of 3 different colored bars
y = [2 2 3; 2 5 6; 2 8 9; 2 11 12];
h = bar(y);  % h will have 3 handles, one for each color of bars

% set 3 display names for the 3 handles
set(h, {'DisplayName'}, {'Jan','Feb','Mar'}')

% Legend will show names for each color
legend() 

If you'd like to display specific bars in the legend,

legend(h(2:3)) %will only show bars 2 and 3

[Joakim Mørk]

How would this be excecuted if you had both x-vals and y-vals?

I've tried it out but it doesnt seem to work out:

x = [1 2 3];
vals = [2 3 6; 11 23 26];
b = bar(x,vals);
set(b, {'DisplayName'}, {'Jan','Feb','Mar'}')
legend() 

[Adam Danz]

In my example there are 3 members per groups and I assign 3 labels to the legend.

In your example, there are 2 members per group but you assign 3 lables which wouldn't make sense. I think what you're looking for are x tick lables.

set(gca, 'XTick', 1:3, 'XTickLabels', {'Jan','Feb','Mar'})