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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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!

Accepted Answer

Peter Perkins
Peter Perkins on 8 Mar 2017
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.
  3 Comments
Robert
Robert on 8 Mar 2017
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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More Answers (1)

Walter Roberson
Walter Roberson on 7 Mar 2017
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'})]
  5 Comments
Walter Roberson
Walter Roberson on 8 Mar 2017
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
However, if you were going to do that, then just
T = array2table(DATA, 'VariableNames', file_list);
with no loop.

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