How to use function table (or timetable) inside a loop to generate a final table that contains a large number of variables (columns) with names

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Robert 2017-3-7

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评论： Robert 2017-3-8

Wondering if anyone could suggest how to use the function table (or timetable) inside a loop to generate a final table that contains a large number of variables (columns) with names?

 %This is my wrong attempt...
 T = array2table(DATA); 
%DATA is an array with 1st column (sorted dates), following 300 columns (data, double), and over 100.000 rows. 
 for kk=1:size(DATA,2)
    name={num2str(file_name_list{kk})}; % Generate individual names to add to next step
    T =[T; array2table(DATA,'VariableNames', {name})]; % Trying to add new names to columns...   
 end
 %... to get something like
 Time                       VarName1   VarName2   ...   VarName300
 '20-Sep-2001 00:00:00'     10         2.5        ...   NaN
 '20-Sep-2001 01:00:00'     NaN        0.34       ...   12
 '20-Sep-2001 02:00:00'     0.1        NaN        ...   0.4
 ...                        ...        ...        ...   ...

Thanks!

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Peter Perkins 2017-3-8

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I'm not sure what is actually in the array DATA. I may have missed that in your description. It sounds like it might be a numeric array with datenums in column 1 and numbers in columns 2:300 (or 2:301?). And then file_list is a 1x300 (1x301?) cell array of char vectors like 'AGR_OCEAN_001'.

So maybe

tt = array2timetable(DATA(2:300), ...
                     'RowTimes',datetime(Data,'ConvertFrom','datenum'), ...
                     'VariableNames',file_list)

No loop needed. But I think we're gonna need to see a real, small example of what you have.

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Peter Perkins 2017-3-8

Yes, thanks.

Robert 2017-3-8

That works great! Thank you to all of you for make time to help people like me to learn and advance in Matlab world. Very appreciated!

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Walter Roberson 2017-3-7

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Almost!

      T =[T, array2table(DATA,'VariableNames', {name})]; % Trying to add new names to columns...

This changes the ";" to ","

For example,

T = array2table(randi(6,5,2))
T = [T,array2table(randi(10,5,7), 'VariableNames', {'A1','A2','A3','A4','A5','A6','A7'})]

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Walter Roberson 2017-3-8

My guess:

 T = array2table(DATA(:,1)); 
 %This now create a Table with one column, which has the dates
 for kk = 2 : size(DATA,2)
    name_cell = file_list(kk); 
    % Generate individual names to add to next step 
    T = [T, array2table(DATA(:,kk),'VariableNames', name_cell)]; 
 end