Is it possible to identify data in a for loop?

I have a code in which I pull files from '.txt' files and run them in a for loop in order to plot them all together. I was wondering if there was a way for me to identify each line separately in the plot. Here is the code and an example file,

myFolder = 'C:\Users\administrador\Desktop\Curves';
d=dir(fullfile(myFolder, '*.txt'))
figure, hold on
for k = 1:numel(d)
    data=dlmread(fullfile(myFolder,d(k).name));
    plot(data(:,4),data(:,5),'LineWidth',3);
    xlim([0 7])
    ylim([0 4])
end

Answer 1

[jonas]

I would probably collect the data in the loop instead and then call plot outside of the loop. Could use something like this:

d=dir(fullfile(myFolder, '*.txt'))
for k = 1:numel(d)
    data=dlmread(fullfile(myFolder,d(k).name));
    x{k} = data(:,4);
    y{k} = data(:,5);
end

figure;hold on
h = cellfun(@plot,x,y,'uniformoutput',1);
xlim([0 7])
ylim([0 4])
legend(h,{d.name})

If you really want to label the data inside the loop then you can set the displayname:

d=dir(fullfile(myFolder, '*.txt'))
figure, hold on
for k = 1:numel(d)
    data=dlmread(fullfile(myFolder,d(k).name));
    h(k) = plot(data(:,4),data(:,5),'LineWidth',3,'displayname',d(k).name);
    xlim([0 7])
    ylim([0 4])
end
legend

[Feliciano Döring]

With the first alternative I get:

%Error using cellfun
%matlab.graphics.chart.primitive.Line output type is not supported. Set
%'UniformOutput' to false.

But the second one works fine, so thank you!

Edit.

I was wondering, why would you assign the plot to a variable?

[jonas]

Odd, cellfun outputs a set of line handles here with my own test files. Could possibly fail if more than one line is stored in the same cell. You could try setting uniformoutput to false and see what is being stored in the variable h.

[Feliciano Döring]

I changed it and it's a 1x21 cell with 1x1 line in each

[Feliciano Döring]

By the way, is there a way to not display the '.txt' extension on the displayname?

[jonas]

Not sure why the first method did not work then, perhaps a release issue.

Sure, just do not pass the 4 last characters

h(k) = plot(data(:,4),data(:,5),'LineWidth',3,'displayname',d(k).name(1:end-4));

[Feliciano Döring]

Thanks!