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Subplot the same three variables from N mat files in a folder

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Hi!
I am trying to use subplot and was looking for tips on how to approach this:
There's a folder full of N .mat files, and each file contains three variables that I want to subplot (R, A, and P). Each .mat file has a unique name beginning with its date.
I am trying to subplot N rows, with 3 columns R, A and P, so that I can see and compare them all together like a gallery.
My intended code goes through each .mat file of N .mat files, loads and plots its R, A and P as columns 1, 2 and 3 of row 1 of N files.
Then it goes to the next .mat file, and loads and plots its R, A and P as columns 1, 2 and 3 of row 2 of N... etc.
..And I'd like all N to be in the same figure. I want to generate a giant figure with, say, 70 rows, and compare R, A and P as three columns alongside each other.
** Edited one day after posting to include my current approach** --
To start with, I am trying to subplot from a test folder containing 3 mat files, and am only plotting R and A variables) (so it's a 3X2 subplot).
I am using a nested for loop and an if.
Here is the code I have so far:
%%
read_folder = '...';
write_folder = '...';
cd(read_folder);
files = dir('*.mat');
N=numel(files);
R_y = [array of numbers]';
A_y = [another array of numbers]';
figure;
fig = gcf;
for i = 1:N
for j = 1:6 %will need to change this as per numel(files).
load(files(i).name, 'R', 'A')
[pathstr,name,ext] = fileparts(files(i).name);
newFilename = fullfile(pathstr,name);
subplot(N,2,j)
if mod(j,2) == 0
subplot(N,2,j);
plot(A_y, A);
else mod(j,2) == 1 ;
subplot(N,2,j);
plot(R_y, R);
end
end
cd(write_folder);
saveas(fig, Image_name, 'png');
cd(read_folder);
end
This makes a 3x2 subplot, but it plots the R and A from just the one mat file in all three rows instead of plotting from each mat file, which is what I'd like for it to do.
Thanks so much for all your tips!! :-)

  8 Comments

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Veena Chatti
Veena Chatti on 3 Jan 2020
Thanks again!
The 3X2 is just a test. I eventually want to use this code to subplot the three variables in about 150 .mat files in each folder.
TADA
TADA on 3 Jan 2020
Does it really all have to be on a single figure?
It sounds like a lot of data, that's going to be hard to read
There might be a more compact way to present it all
Stephen Cobeldick
Stephen Cobeldick on 6 Jan 2020
Note that using absolute/relative filenames is more efficient and easier to debug, comapred to using cd Changing the current directory just to access data files is not recommended.

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Accepted Answer

Pujitha Narra
Pujitha Narra on 6 Jan 2020
As far as I understand, there must 6 subplots(for the sample code written) in a single plot, each row representing a .mat file.
But the code above is trying to make 6 subplots for each of the .mat file which explains the anomoly you are seeing.
Small changes to the code will help you.
j=1;
for i = 1:N %number of .mat files
subplot(N,3,j)
%....code to plot first variable here
j=j+1;
subplot(N,3,j);
%....code to plot second variable here
j=j+1;
subplot(N,3,j);
%....code to plot third variable here
j=j+1;
end

  1 Comment

Veena Chatti
Veena Chatti on 10 Jan 2020
Pujitha, thanks a ton for this! It now does exactly what I was looking for. I appreciate your help! Thanks again.

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