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How to include a wide table's VariableDescriptions as an additiolnal column when stacking the table?

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I would like to make a wide table's VariableDescriptions as an additional column when I stack the table. I have written some codes to do it. They work (in a dirty manner). Is there a better way?
T = cell2table({'A', 2, 3, 3; 'B', 5, 5, 7}, "VariableNames", {'AB', 'x', 'y', 'z'});
% variable descriptions
T.Properties.VariableDescriptions = {'AB', 'xdes', 'ydes', 'zdes'};
S = stack(T, 2:4, "IndexVariableName",'xyz', 'NewDataVariableName','value')
S = 6×3 table
AB xyz value _____ ___ _____ {'A'} x 2 {'A'} y 3 {'A'} z 3 {'B'} x 5 {'B'} y 5 {'B'} z 7
% duplicate the table, using the variable descriptions as new variable names.
T2 = T;
T2.Properties.VariableNames = T.Properties.VariableDescriptions;
% stack the second table
S2 = stack(T2, 2:4, "IndexVariableName",'xyzdes', 'NewDataVariableName','value');
% add the descriptions as a new column to the first table
S.xyzdes = S2.xyzdes;
S = movevars(S, "xyzdes", "After", "xyz")
S = 6×4 table
AB xyz xyzdes value _____ ___ ______ _____ {'A'} x xdes 2 {'A'} y ydes 3 {'A'} z zdes 3 {'B'} x xdes 5 {'B'} y ydes 5 {'B'} z zdes 7

Accepted Answer

Divyanshu on 18 Apr 2023
The key concept used here is of a Map where variable names of the table are keys, and their values are the variable descriptions. For simplicity I have assumed names to be in names’ and descriptions in desc.
Here is a demo script of doing the same where a new column is added at the end of the stacked table:
names = ["x" "y" "z"];
desc = ["xD" "yD" "zD"];
M = containers.Map(names,desc);
col2 = S(:,2);
len = height(col2);
colN = []
for i=1:len
colN = [colN;string(M(string(col2{i,:})))];
colN = table(colN)
S = [S colN]
In the above script S is the stacked table that was created by your code.
The vector ‘colN is the new column vector which holds the descriptions.
Please refer to the following documentation to get more information about Maps:
  1 Comment
Simon on 23 Apr 2023
Edited: Simon on 23 Apr 2023
Thanks for the answer. I didn't know 'containers.Map' before. But Matlab has just created 'dictionary', which serves similar purpose and can take more flexible data type. Anyway, key-value mapping is a great idea in solving my problem.

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