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Can I dynamically change a structure name

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TastyPastry
TastyPastry on 26 May 2016
Edited: Stephen Cobeldick on 27 May 2016
I have a function which takes in multiple .mat files, reads part of them and consolidates them into a cell array.
Currently my code looks like this:
myData = cell(numel(files),numel(headers)); %preallocate
for i=1:numel(files) %loop through the total number of files
currPath = [filepath files{i}]; %get the current file path
load(currPath);
myData(i,:) = (varName).database(headers) %grab the data
end
In this code, headers are indices of the columns I need data from. The issue lies in the myData(i,:) = ... line where I need to dynamically change (varName). I originally had it hard coded in because I thought the .mat files had consistent file names for the structure array I'm trying to read from, but it turns out that each folder has a different variable name consistent with the name of the folder.
I tried:
%find what the variable name is
varName = strtok(folderName,'_');
But the issue I'm running into is that (varName) doesn't work to substitute in a variable name the same way it works when substituting for a field name when accessing a structure. While I'm able to find the correct imported variable name and store it as a string, it doesn't let me use it as a variable.
I've also tried:
eval(sprintf('%s', varName));
But it just turns out I have no idea how to use eval().
Is there any workaround? I hope I don't have to use a list of try/catch statements...

Accepted Answer

Adam
Adam on 26 May 2016
Use the version of load with an output argument - i.e.
loadedStruct = load( currPath );
Then you will get the contents of your file as fields of a struct and you can use dynamic strings for the field name then:
myData(i,:) = loadedStruct.(varName).database(headers)
  1 Comment
TastyPastry
TastyPastry on 26 May 2016
Oh wow didn't even think about that. Thanks!

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