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Name variables according to string

Asked by Julian Pires on 5 Jun 2019
Latest activity Commented on by Stephen Cobeldick on 6 Jun 2019
Hello, my problem is as follows:
  • I have a series of folders named "100-'some text", "101-'blahblah'", "102-...", "103-..."
  • Each folder has a .txt file with columns of data used to generate a .mat file named "data"
  • These .mat files contain 1 struct named "data" with 2 fields: name & data. The names include 'Time', 'Speed', 'Temp', etc.
So I'd like to compare data between the folders by plotting Time vs. Temp for folder 100 and 101, but when I open the .mat files it overwrites the previous because they share the same name ("data").
What I'd like to do is open the .mat files and rename the signals according to the folder number. ie) "Time" will become "Time_100".
I know I should avoid using EVAL, but is there another way to do this? Or is there a way to avoid the problem entirely by naming the struct in each .mat file to "data_100"? I would prefer to extract the names in each struct, change them by appending the folder number, and then saving that workspace.
Thoughts?
Thanks

  1 Comment

"I know I should avoid using EVAL..."
Yes, you should.
"..., but is there another way to do this?"
Of course: use an array (e.g. a structure array or a cell array) and indexing.
"Or is there a way to avoid the problem entirely by naming the struct in each .mat file to "data_100"?"
That does not avoid the problem, it just makes your code more complex! The simplest solution is when each .mat file contains variable using the same name, just as you described.

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1 Answer

Answer by Rik
on 5 Jun 2019
 Accepted Answer

Why not store them in a struct array? If all mat files have the same fields that should work very well.

  2 Comments

Ideally, they would be kept in their own named folder as new data is added. I think I just need to rename the structures and their 'names' field with the folder number appended but I'm not sure how to rename the structure that way. Renaming the fields is easy
" I think I just need to rename the structures..."
Rik's suggestion to use a structure array is simpler and much more efficient.

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