Change variable name based on what loop it is on

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Annie
Annie le 14 Avr 2025 à 16:33
Modifié(e) : Stephen23 le 15 Avr 2025 à 4:41
I have a user input a vector for the variable titled 'k1'. A loop is set up where the input conditions are the same, but the variable name must be changed in order to perform some operations and store the data. I would like it to change based on which loop it is performing, like k1 might be given the name k2 on the second loop. I don't know how I could do this simply or if doing this is possible.
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Stephen23
Stephen23 le 14 Avr 2025 à 18:08
Modifié(e) : Stephen23 le 15 Avr 2025 à 4:41
"I don't know how I could do this simply or if doing this is possible."
It is possible, but is best avoided:
The neat, simple, robust, reliable, efficient alternative is to use indexing. You should use indexing.

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KALYAN ACHARJYA
KALYAN ACHARJYA le 14 Avr 2025 à 17:48
Optimized Memory Usage Strategy:
To efficiently utilize memory based on the type of output variable k, consider the following approach:
  1. If k is a scalar output (single numeric value per iteration):Preallocate a numeric array to improve performance and memory usage.
k = zeros(array_size1, array_size2); % Preallocate for scalar values
for i = 1:array_size
k(i) = ... ; % Assign scalar result
end
2. If k stores vectors or non-scalar data types (e.g., strings, structures, or arrays):
Use a cell array to accommodate varying data sizes/types.
k = cell(Cellarray_size1, Cellarray_size2); % Preallocate cell array
for i = 1:array_size
k{i} = ... ; % Assign vector or other complex result
end

Plus de réponses (2)

Walter Roberson
Walter Roberson le 14 Avr 2025 à 17:43
Modifié(e) : Walter Roberson le 14 Avr 2025 à 17:43
It is possible to do this.
It is not possible to do this simply.
We firmly recommend that you do not do this.

dpb
dpb le 14 Avr 2025 à 17:58
While it can be done, it almost never should be the way..."there be dragons!" and slow, obfuscated and very difficult to debug code. See <Do not use globals or eval>. The direct link is to @Matt Fig's answer, but the overall discussion/thread is informative and valuable. The offcial Mathworks documentation link <Alternaives to the eval Function> discusses exactly the thing you mention as its first use case...

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