How to use a char variable name as a numeric variable

6 次查看（过去 30 天）
Jose Andrés
Jose Andrés 2015-4-26
编辑： Stephen23 2019-6-19
Hello everyone,
I have concatenated images and generated some new variables with this loop:
% mymatrix=768x128
n=size(mymatrix,1)/size(mymatrix,2);
for k = 1:n-1
v = genvarname('IOri',who);
eval([v ' =mymatrix((128*k):(128*k+127),:)']);
...
% And here I need to use the value of my new variable
end
I need to use the values of the variables "v" in every loop called 'IOri','IOri1','IOri2'... to execute other code lines before the loop ends.
I can't use this v variable directly because it contains a char name of the IOrik created, and I can't use this IOrik name because it changes in every loop iteration. I need to get this IOrik value assigned to the v after his creation.
Hope I have explained myself propertly.
Thank you!

请先登录，再回答此问题。

采纳的回答

Mohammad Abouali
Mohammad Abouali 2015-4-26
编辑：Mohammad Abouali 2015-4-26
Similar question has been asked.
Try the answers on this post:
http://www.mathworks.com/matlabcentral/answers/213097-having-trouble-with-changing-matrix-name
Generally the approach that you have used is not recommended. Although pretty much on that post the question is answered by pretty much clearing the question. But this is one of those cases that I think everyone agrees that it is ok.
So, if you read that post people have suggested other methods, that does not end up to have different variable names. There are much easier way to handle multiple images.
In your case that you are dealing with multiple images, it is not bad idea to check on imageSet(), especially if you have later versions of MATLAB.
by the way, MATLAB has montage() commands which pretty much concatenates multiple images. Don't rewrite your own image concatenation unless for some other reason you need to.

更多回答（2 个）

Stephen23
Stephen23 2015-4-26
编辑：Stephen23 2019-6-19
Use a simple cell array loop instead:
C = cell(size(mymatrix));
n = size(mymatrix,1)/size(mymatrix,2);
for k = 1:n-1
C{k} = ... any calculations here
end
Avoid creating dynamically named variables in MATLAB
https://www.mathworks.com/help/matlab/matlab_prog/string-evaluation.html
https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval
Jose Andrés
Jose Andrés 2015-4-27
Thank you both of you. Finally I did with a simple loop and it works perfectly.
Thank you so much.

类别

在 Help Center 和 File Exchange 中查找有关 Whos 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by