How to write a changing table name in setdiff function?

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Davin
Davin le 7 Juil 2016
Modifié(e) : Stephen23 le 8 Juil 2016
Hello,
I would like to know how to write a function inside which there is a changing table name.
I have created a table which will change at each loop
eval(['Port' num2str(i-1) '= Portfolio'])
At some point I need to make a difference between this table and a new portfolio so i used the function setdiff
for example, there is a Port1 which is created, now I need to execute this :
[i,j] = setdiff(Port1(:,2), Portfolio(:,2))
Port1 is created by the eval function. Can you tell me how I can incorporate the name of the table dynamically inside the setdiff function which will pick up automatically the newly created table ( port2, port3....). I tried this but its not working :
[i,j] = setdiff(['Port' num2str(i-1)](:,2),Portfolio(:,2))
Thank you very much for your help
D
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Stephen23
Stephen23 le 8 Juil 2016
Modifié(e) : Stephen23 le 8 Juil 2016
@Davin: it is almost always a bad idea to create variable dynamically. Read this to know why:
https://www.mathworks.com/matlabcentral/answers/196952-how-to-create-new-variables-in-batches-with-strcat
Much simpler and more reliable is to use indexing. You can easily put the tables into cell arrays, and using indexing is then trivial.

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Guillaume
Guillaume le 8 Juil 2016
Despite what's been suggested, there is no need to convert the tables to cell arrays (and lose information such as column and row names). Just put the tables into a cell array.
Numbered variables are a clear indication that what is in the variables should be stored together in one container, not as individual variables. In this case a cell array of tables would be the most appropriate.
portnumber = 5;
Port{portnumber} = Portfolio; %store in cell array
[coldiff, loc] = setdiff(Port{portnumber}(:, 2), Portfolio(:, 2))
No eval needed, just straightforward indexing and you still get to manipulate tables with all the advantages that they bring.
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Davin
Davin le 8 Juil 2016
Its exactly what I did, and its far much simpler.
Thanks Guillaume.

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