How a table columns are named using MATALB

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C PRASAD 2022-3-5

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https://ww2.mathworks.cn/matlabcentral/answers/1664089-how-a-table-columns-are-named-using-matalb

评论： Simon Chan 2022-3-11

I have a fetaure table with 5*10 size.Now I woul like to name each of the Coloumns

I would like to name ecah coloumn and also again 5 coloumn need to give name with Title1 as shown below.Please help me using MATLAB

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Stephen23 2022-3-5

编辑：Stephen23 2022-3-6

Adding "headers" (i.e. column/variable names) is easy if you convert the data to a table: https://www.mathworks.com/help/matlab/ref/array2table.html

However a heirarchy of column/variable names like you show is not possible in one table :https://www.mathworks.com/matlabcentral/answers/541568-nested-tables-with-duplicate-sub-column-names

You could create nested tables, but that does complicate accessing and processing your data.

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Answer 1

Simon Chan 2022-3-5

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https://ww2.mathworks.cn/matlabcentral/answers/1664089-how-a-table-columns-are-named-using-matalb#answer_910379

在 MATLAB Online 中打开

Something like the following may be similar to what you want.

clear; clc;
combine_vector = randi(10,5,10);
Title1 = array2table(combine_vector(:,1:5),'VariableNames',compose('feature%d',1:5));
Title2 = array2table(combine_vector(:,6:10),'VariableNames',compose('Sfeature%d',1:5));
T = table(Title1,Title2)
T = 5×2 table
                             Title1                                                        Title2                            
    feature1    feature2    feature3    feature4    feature5    Sfeature1    Sfeature2    Sfeature3    Sfeature4    Sfeature5
    ________________________________________________________    _____________________________________________________________

       1            9          10          6            3           5            2            9            2            4    
       3           10           4          8           10           4           10           10            4            4    
       2            6           1          8            7           4            7            5            8            5    
       6            2           2          8            7           2            6            8            6            2    
       6            6          10          2            9           2            4            8            2            8    

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Simon Chan 2022-3-5

在 MATLAB Online 中打开

Please refer to the following:

As mentioned by Stephen, it becomes a little bit complicated.

clear; clc;
Nz = 15;
combine_vector = randi(10,28,75);                                                   % Simulate data
TopTitle = compose('H%d_Features',1:Nz);                                            % Prepare the top title
SubTitle = ["Energy","Variance","Standard_Deviation","Waveform_Length","Entrophy"]; % Prepare the sub title
%
T = cell(1,Nz);                                                                     
for k = 1:Nz
    Ttemp = array2table(combine_vector(:,5*(k-1)+1:5*(k-1)+5),'VariableNames',strcat(SubTitle,num2str(k)));
    T{k} = table(Ttemp,'VariableName',TopTitle(k));
end
Tcombine = cat(2,T{:});
Tcombine(:,1:3)                         % Table is too big and just display the first 3 columns
ans = 28×3 table
H1_FeaturesH2_FeaturesH3_FeaturesEnergy1Variance1Standard_Deviation1Waveform_Length1Entrophy1Energy2Variance2Standard_Deviation2Waveform_Length2Entrophy2Energy3Variance3Standard_Deviation3Waveform_Length3Entrophy3____________________________________________________________________________________________________________________________________________________________________________________________________________________________________

       1           2                 1                     8               4           8           6                 7                     3              10           4           8                 9                     8               2    
       7           9                 5                    10               4          10           9                10                    10               9           8           5                10                     8               7    
       5           4                10                     6               5           7           2                 1                     4               8           9           4                 8                     5              10    
       9           6                 9                     4               1           9           2                 4                     3              10           6           4                 4                     9              10    
       8           9                 5                     7               3           8           7                 8                     9               5           4           6                 4                     6               3    
       5           4                 3                     2               4           5           4                 4                    10               9           5           7                10                     8               6    
       3           8                10                     8               8           6           7                 9                     4               4           8           3                 9                     5               9    
       8           1                10                     8               9           4           3                10                     7               8           3           5                 2                     3               6    
       5           5                 4                     5               2           9           7                 9                     1               7           2          10                10                     4               4    
       6           3                 4                     1               4           3           2                 8                     3               6           3           5                 4                     5               1    
       1           1                 4                     8               4           2           2                 4                     2               9           5           9                 8                     4               9    
       5           6                 8                     6               4           1           5                 5                     9               6           1           2                 5                     3               5    
       7           1                 4                     7               6           1           7                 3                     7               2           9           5                 6                    10               5    
       3           3                 2                     9               7           9           7                10                     6               1           4           1                 3                     8               5    
      10           3                 2                     4               3          10           8                 9                     7               9           4           1                 5                     7               9    
       8           1                 3                     1               5           6           9                 3                     4               7           1           1                10                     3               3    

C PRASAD 2022-3-11

Thank you so much sir.If I wolud like to save all titles first columns to one variable and all second coloumns to another variable and so on.

A=Title1.features1(:,1)

B=Title1.Sfeatures2(:,2)

I can use these but if I have a 12*15 size and I wolud like to save 1,6,11 coumns data to one variable and 2,7,12 to another variable ,3,8,13 and 4,9,14 and 5,10,15 to another variable using any loop.Please help me with this sir

clc

clear all

close all

X=randi(10,12,75);

Nz = 15;

TopTitle = compose('H%d_Features',1:Nz); % Prepare the top title

T = cell(1,Nz);

for k = 1:Nz

arr=X(:,5*(k-1)+1:5*(k-1)+5);

vnm =strcat({'Energy','variance','std','wl','entrophy'},num2str(k));

Ttemp = array2table(arr,'VariableNames',vnm);

T{k} = table(Ttemp,'VariableName',TopTitle(k));

end

Tcombine = cat(2,T {:});

Prasad=Tcombine(:,1:Nz);

%% Channel1 features %%

s11=Prasad.H1_Features(:,1);

s12=Prasad.H2_Features(:,1);

s13=Prasad.H3_Features(:,1);

s14=Prasad.H4_Features(:,1);

s15=Prasad.H5_Features(:,1);

%% Channel2 Features %%

s21=Prasad.H1_Features(:,2);

s22=Prasad.H2_Features(:,2);

s23=Prasad.H3_Features(:,2);

s24=Prasad.H4_Features(:,2);

s25=Prasad.H5_Features(:,2);

%% Channnel3 Features %%

s31=Prasad.H1_Features(:,3);

s32=Prasad.H2_Features(:,3);

s33=Prasad.H3_Features(:,3);

s34=Prasad.H4_Features(:,3);

s35=Prasad.H5_Features(:,3);

%% Channel4 Features %%

s41=Prasad.H1_Features(:,4);

s42=Prasad.H2_Features(:,4);

s43=Prasad.H3_Features(:,4);

s44=Prasad.H4_Features(:,4);

s45=Prasad.H5_Features(:,4);

%% Channel5 Features %%

s51=Prasad.H1_Features(:,5);

s52=Prasad.H2_Features(:,5);

s53=Prasad.H3_Features(:,5);

s54=Prasad.H4_Features(:,5);

s55=Prasad.H5_Features(:,5);

I want to use a loop to save channel 1 feature into one variable and like wise all the featutres sir.Please help me with the help of any loop function

Stephen23 2022-3-11

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Simon Chan 2022-3-11

在 MATLAB Online 中打开

There is no need to save them in different variables. Stephen's recommendation is absolutely right.

In case you would like to use data on column 1,6,11. You can directly retrieve them from the variable combine_vector as follows:

combine_vector = randi(10,28,75);  
combine_vector(:,[1 6 11])
ans = 28×3
   4    10
   6    10
   7     1
   7     4
   3     2
   2     6
   3    10
   8     4
  10    10
   3     8