Plot legend contours messed up

I am creating a plot where the data to be plotted is calculated from data in a set of text files. The data is grouped for plotting based on a text string in the filenames. When I add a legend for these groupings ("clumps") the colours in teh legend are messed up.

The script is quite big and messy, so I've created a simpler test script and text files with just two clumps. These are in the attached zip file. The plot created by the test script is this:

Some of the text files don't have all the required data. The script will then try to plot [NaN NaN] for those files.

The legend is not messed up if I remove these text files. In the files provided, delete the first two "Scar" files and you get this:

Where am I going wrong?

UNfortunately, I cannot change the approach of constructing the plot from the text files. The text files are generated by other software and there can be several hundred of them, in up to 12 clumps.

Answer 1

[dormant]

After a bit of fiddling it was clear that my overall approach was totally wrong. My script had three tiled subplots and I was dancing around tiles and text files. Then I was trying to add the legend to each tile. Modifying this script was murder.

It's much easier to read all the text files into arrays or structures first. Then do the plots. I don't know why I didn't use this approach.

Thanks to all who posted. I'll come back with a new question if I run into problems with the new approach.

Answer 2

[William Rose]

@dormant,

Try the attached. Good luck.

Edit: Update the script, as descirbed in my comment below.

[William Rose]

@dormant,

Thanks for posting a simplified version of your script, to make it easier for others to assist you. It would be great if more people on this site followed your good example.

[dormant]

Thanks. One problem with submitting a simplified script is transferring the changes to the big messy script. My first attempt failed, but I'm sure I'll work it out.

[William Rose]

@dormant, good luck.

I edited my earlier answer, by updating the script. My first script used

legend( pHandle(legPlot), 'location', 'northeast' );

and the new version uses

legend( pHandle(legPlot), legendItems, 'location', 'northeast' );

The original script which you posted uses

legend( legendItems, 'location', 'northeast' );

where legendItems is a cell array containing two strings. When legend() sees this, it uses the two strings, and it uses the symbol and color info for the first two data sets in the plot. But what we want, in this case, are the symbol and color info for set 1 and set 4, since sets 1 and 4 correspond to clump 1 and clump 2. Therefore I searched Matlab Answers for "how to change the legend order" and I found an answer here - thank you, @Afiq Azaibi. (@Afiq Azaibi gives three ways to do it; I used method 1.) I could also have read the help for legend() and noticed the optional argument "subset".

[dormant]

Thanks. I'll fiddle a bit and get back to you.

[Afiq Azaibi]

Glad to hear my other answer was able to help, @William Rose. Thanks for bringing attention to it.

To echo the relevant information from that post, if you want certian objects to appear in a legend in a certain order, the best practice is to speicfy the objects in the legend() command. This syntax is referenced as subset in the doc and is what the William points out as my first method.

[dormant]

Thanks for that info.