Indexing Large Numbers of Data by Name

Hi! So I'm trying to write a software for gathering data from tensile tests. I'm fine writing the code for each individual test results, but I'm struggling to find a way to index large amounts of data. Basically, I'm going to recieve an xlsx file for each test named TestRun2_1_29_2021 or TestRun3_1_29_2021, and I will have somewhere around 150 of these tests to run. Each xlsx file contains two column vectors- one for stress, and one for strain. I currently am trying to use a structure array to save the vectors, but I don't know how to navigate through the array.

%First I'm loading the full results, which consists of (for this brief example) 7 different tests 
data=load('TensionTest1_19_21.mat');

% Ideally I could navigate through this structure with some simple for loop like

for i=1:length(data)
    plot(dataAinT(i),dataEssT(i))
end
%etc but I don't know how to create indexable variables like that. 

If anyone has any ideas how to load ~150 tests through a for loop and just have some loop run all the calculations, I'd really appreciate it.

Again, my primary concern is I don't have any clear understanding how to create a structure of indexable vectors, such as the structure array I have now.

Answer 1

[Walter Roberson]

dinfo = dir('TestRun*.xlsx');
filenames = {dinfo(K).name};
numfiles = length(filenames);
all_data(numfiles,1) = struct();   %preinitialize struct

for K = 1 : numfiles
   thisfile = filenames{K};
   [~, basename, ~] = fileparts(thisfile);
   data = readmatrix(thisfile);
   all_data(K).dataAinT = data(:,1);
   all_data(K).dataEssT = data(:,2);
   all_data(K).name = basename;
end

for K = 1 : numfiles
   plot(all_data(K).dataAinT, all_data(K).dataEssT, 'DisplayName', all_data(K).name);
   hold on
end

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[Sam Vellequette]

Question-

I can almost get everything out of this from what you're doing. I'll admit, this is mostly beyond me, so for reference sake so that I can teach myself, I have just a brief string of questions.

First, when I run this code, it says that "thisname" is not defined- I think what you're trying to do is assign the name of the file to "basename," but I'll admit the code is stuck here. I changed it to thisfile, so that it now looks like

thisfile = {dinfo.name};
   [~, basename, ~] = fileparts(thisfile);

But now the error is

Error using fileparts (line 37)

Input must be a row vector of characters or string scalar.

Error in Untitled (line 11)

[~, basename, ~] = fileparts(thisfile);

Which I can assume means that it doesn't know how to read the

Also,

thank you!! Even if the code has a small hitch in it, I've already learned a lot from this one answer about arrays, a few functions, logical operators, etc.

[Walter Roberson]

Corrected, thisname should have been thisfile .

It is not the name of the file itself that is being assigned to basename: fileparts is stripping off the suffix (and directory) to get just the "base name" of the file.

[Sam Vellequette]

Hey walter, I see you just edited your answer. I just wanted to comment again to bring it to your attention, but I changed out the thisname to thisfile and I'm getting the error in the comment above. I just edited my comment, so sorry about the timing!

[Walter Roberson]

Sorry, fixed again.

[Sam Vellequette]

Hey, I did one quick last revision to attempt to condense it. Here's the final product. Thank you again!

dinfo = dir('TestRun*.xlsx');
numfiles = length(dinfo);
all_data(numfiles,1) = struct();   %preinitialize struct

for K = 1 : numfiles
   filenames = {dinfo(K).name};
   [~, basename, ~] = fileparts(char(filenames));
   data = readmatrix(char(filenames));
   all_data(K).dataAinT = data(:,1);
   all_data(K).dataEssT = data(:,2);
   all_data(K).name = basename;
end

for K = 1 : numfiles
   plot(all_data(K).dataAinT, all_data(K).dataEssT, 'DisplayName', all_data(K).name);
   hold on
end
legend show