Using name of saved matrix

Hi,

I'm trying to plot multiple outputs from a script on the same graph. As it stands, my script outputs the array I want to plot in a variable called "diff". I ran this script three times, changing my input data, and after each run I right clicked the variable "diff" and saved it as a .mat file with a different name (ie data1.mat, data2.mat, data3.mat). After clearing the workspace, I attempted to import these three .mat files into the workspace again (by dragging and dropping from file directory). However, I noticed that each time it imports the file with the variable name "diff" and not the file name. This means I only have one variable in my workspace and I cant plot the three lines as I expected. Is there an easy way of importing the variable with a new name each time, if it detects that it already exists? Or am I going about this all wrong?

Thanks in advance.

Answer 1

[Johannes Hougaard]

I think you should go a different route where you don't save your variables to .mat files and simply keep the variables in your MATLAB workspace without clearing.

run('script'); % execute your script however you like to
data1 = diff;
run('script'); % execute your script again however you like to
data2 = diff;
run('script'); % execute your script again however you like to
data3 = diff;
plot([data1;data2;data3]');

Or to rename you variable diff (in the script) before running it the second time and third time (e.g. to diff2/diff3)

If you have to store the data in files you could specify an output to the load call

data1 = load('data1.mat')
data2 = load('data2.mat')
data3 = load('data3.mat')
plot([data1.diff;data2.diff;data3.diff]')

[Steven Lord]

In addition to what Johannes Hougaard wrote, diff already has a meaning in MATLAB. If you accept that you're not going to be able to call the diff function while a variable named diff exists, you can use that name but usually we recommend avoiding the names of functions in MATLAB when naming your variables.

[Ted Baker]

Thanks Johannes, much appreciated. It works now.

Thank you also, Steven, for letting me know about diff!