Access variables with naming in workspace

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I have a workspce full of data1, data2, data3.....,data100
They are all arrays with (1,n)
Instead of do it one by one via
```
matr(1,:)=data1
matr(2,:)=data2
etc
```
How can I use a loop to form this matrix
  1 Comment
Stephen23
Stephen23 on 14 Sep 2022
Edited: Stephen23 on 14 Sep 2022
"I have a workspce full of data1, data2, data3.....,data100"
Having lots of numbered variables in the workspace is a sign that you are doing something wrong.
You did not tell us the most important information: how did you get all of these arrays into the workspace? The point where they are imported or created would be the correct place to fix your code, rather than what you are trying to do.
Whatever you do, do NOT use EVAL, ASSIGNIN, or follow any other subpar advice of that kind.

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Accepted Answer

Stephen23
Stephen23 on 14 Sep 2022
This appears to be a follow up from your question from seven hours ago:
The best solution by far is to not get into the situation where you have lots of numbered variables in the workspace:
For example, you can easily LOAD into an output variable, which makes your data very easy to access (unlike what you are doing now) It assumes exactly one variable per MAT file.
N = 25;
C = cell(1,N);
for k = 1:N
F = sprintf('data%d.mat',k);
C(k) = struct2cell(load(F));
end
All of your imported filedata wll be in the cell array C. Note that you can trivially loop over all of C, or access its contents individually. For example, the data for the second file:
C{2}

More Answers (1)

Chunru
Chunru on 14 Sep 2022
First of all, try to change the program that produces data1 to data100 by using multidimensional array or cell array if possible.
If that is not feasible for any reason, you can use eval:
matr = zeros(100, n)
for i=1:100
matr(i,:) = eval("data"+i)
end
  7 Comments
Walter Roberson
Walter Roberson on 14 Sep 2022
There is no point teaching someone to use eval until they have actually encountered a situation that could not avoid using eval.

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