How to assign a name to a Table given set of names?

1 次查看（过去 30 天）
Edson
Edson 2016-4-6
编辑： Stephen23 2016-4-6
Hi folks. I have a long code which runs every time with the number of items a set. For instance I have a set: Subjects = {Name1,Name2,Name3}. My FOR produces 3 different tables/matrixes: A, B and C. So each time the FOR statement runs, it overwrites the tables generated for each different subject. Is there a way to insert a code inside my FOR statement to store each table/matrix (A,B,C) and name each after the subject? For instance, something like this:
Subjects = {'Name1','Name2','Name3'}
for i=1:length(Subjects)
A = magic(2)
B = magic(3)
C = magic(4)
strcat('A_',Subjects(1)) = A % These were my best attempts, But It doesn't work.
strcat('B_',Subjects(2)) = B
strcat('C_',Subjects(3)) = C
end
% Any help much appreciated.
  2 个评论
Adam
Adam 2016-4-6
I assume you mean matrices rather than tables. A table is now a specific data type in Matlab so it is useful to be as specific as you can with terminology. Your code suggests these are simply matrices though.
Stephen23
Stephen23 2016-4-6
编辑：Stephen23 2016-4-6
Use Adam's answer, it is the best solution to your problem.
Creating variables dynamically is a really bad way to code, which is explained in lots of threads on this forum:
http://www.mathworks.com/matlabcentral/answers/196952-how-to-create-new-variables-in-batches-with-strcat

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Ralf
Ralf 2016-4-6
编辑：Ralf 2016-4-6
Hi Edson,
would that work for you?
assignin('base', ['A_' Subjects{1}], A);
  3 个评论
显示 1更早的评论
Guillaume
Guillaume 2016-4-6
编辑：Guillaume 2016-4-6
As a rule, do not use assignin, evalin, eval and similar. Do not create variable names dynamically and do not embed metadata in variable names. The metadata belongs in the content of the variable not its name.
Creating variable names dynamically is slow, is a nightmare to debug, makes subsequent code a lot more complicated, and may also not always work.
Adam's answer is a much better way of doing what you want.
Ralf
Ralf 2016-4-6
Guillaume, you are absolutely right. Assignin and evalin are "quick and dirty" solutions. I must admit that Adam's solution is much better.

请先登录，再进行评论。

更多回答（1 个）

Adam
Adam 2016-4-6
编辑：Adam 2016-4-6
Taking your current solution and making minimal changes, rather than starting from scratch...
Subjects = {'Name1','Name2','Name3'}
for i=1:numel(Subjects)
A.( Subjects{i} ) = magic(2)
B.( Subjects{i} ) = magic(3)
C.( Subjects{i} ) = magic(4)
end
will give you structs A, B and C with a field for each subject containing the relevant matrix.
You can then get hold of these fields using dynamic strings in the same way I do above.
  1 个评论
Edson
Edson 2016-4-6
Thanks very much Adam for your answer. I think I can work with Ralf's and yours on my code. Have a great day!

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Data Type Identification 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