MATLAB: Storing tables in an array and calling them whithin a for loop

arrayfor looptable

I am a novice in MatLab. I have 30 different tables that imported in Matlab as CSV files. I want to choose two pairs of the tables and read a column Return of them and store it in ret_1 and ret_2 variables. Something like the following code:
data = {'AAPL', 'AXP', 'BBN'};
for i = length(data)
    for j = length(data)
         ret_1 = data(i).Return;
         ret_2 = data(j).Return;
    end
end
But I get an error, as data(i) doesn't include the content that I want to. I tried
eval(data(i)) but it says that eval() works only with strings and not arrays.
My data looks like the following in CSV files that I imported them into MatLab.
'AAPL' = 
     Date      Low       Close        Return
6/3/1997    16.750    16.935        16.687      
6/4/1997    16.625    16.756        16.625      
6/5/1997    16.625    17.125        16.687      
'AXP' =
   Date       Low         Close       Return
6/3/1997    69.079     70.075       68.750  
6/4/1997    69.079     69.079       68.500  
6/5/1997    68.078     69.876       67.750

Best Answer

You've shown your data, but that can't possibly be output from MATLAB because
'AAPL' =
is not something MATLAB would ever display. I'm gonna assume you've done something like
aapl = readtable('aapl.csv');
axp = readtable('axp.csv');
...
It's almost never a good idea to try to do this via an eval. A reasonable thing to do might be to use a scalar struct with fields named 'aapl', etc. So
data.aapl = readtable('aapl.csv');
data.axp = readtable('axp.csv');
and then
fn = fieldnames(data);
for i = 1:length(fn)
    for j = 1:length(fn)
        ret_1 = data.(fn{i}).Return;
        ret_2 = data.(fn{j}).Return;
    end
end
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