How can I get a legend that identifies ALL series shown on a group of plots?

I have 9 subplots on one figure. 7 of those 9 subplots, including the last subplot, only have 3 data series associated with the plots. However, the other 2 have 4 data series. How do I get the legend to retain the information about ALL of the series shown in the figure? See attached image. Notice that plots 5 and 6 have observed data on them, but the others (including the last one) does not. I need to the legend to reflect the observed data.

[Matthew]

I believe the legend is associated with each individual axis rather than the figure, so there's probably no built in way to do this.

However, you could try making a hidden axis on the figure that contains a dummy series for each series in the figure. You could then create a legend for that hidden axis, and force the legend to be visible, even though its parent axis is hidden. . .

Answer 1

[Kelly Kearney]

To do this, save the handles of the lines you want labeled and pass these to the legend command. They don't have to all share a parent figure.

ax(1) = subplot(2,2,1);
h1 = plot(rand(10,3));
ax(2) = subplot(2,2,2);
h2 = plot(rand(10,2));
ax(3) = subplot(2,2,3);
h3 = plot(rand(10,2));

set([h1;h2;h3], {'color'}, {'r';'g';'b';'c';'m';'y';'k'});
legend(ax(3), [h1;h2;h3], '1','2','3','4','5','6','7');