Creating new table from another table

Hello,

i have following problem. I have a 35049x297 table. Now i would like to cut out specific columns with an if command and put these columns in a new table.

VarNames = Daten2.Properties.VariableNames; 

for i = 1:columns

if contains(VarNames{1,i},'EN')
   
    newtable{i} = table(Daten2.VarNames{1,i});
    
end

This is my code but it doesnt work, i dont know why? can someone help me with that? Thanks for the help!!!

[Ayush Singhal]

Hi,

Please refer below links:

https://www.mathworks.com/matlabcentral/answers/345293-check-a-column-if-a-condition-is-met-use-those-value

https://www.mathworks.com/matlabcentral/answers/387475-how-do-i-put-a-condition-into-a-specific-column-for-matlab

Thanks,

Ayush

[Benedikt Skurk]

Ok i got it..

But the last problem i have is that he doesnt transfer the column headers.

so for example first column header is PE EN Neuruppin_1 and second header is PE EN Wittst_3

U have a solution for that?

Answer 1

[Scott MacKenzie]

You have several problems in your code. The assumtion in your question is that you want to create a new table (newtable) containing columns in the existing table (Daten2) where 'EN' appears in the column name. Here's one way to acheive this:

VarNames = Daten2.Properties.VariableNames; 
columns = width(Daten2);

j = 1;
for i = 1:columns
    if contains(VarNames{i}, 'EN')   
        newtable(j) = Daten2(:,i);
        newtable.Properties.VariableNames{j} = VarNames{i};
        j = j + 1;    
    end
end

[Benedikt Skurk]

Thanks for ur respond!!

My code is now following:

columns = width(Daten2);
j = 1;

for i = 1:columns
    if contains(VarNames{i},'EN') 
        newtable{j} = Daten2{:,i};
        j = j + 1;    
    end
end 

but i get as a result for newtable this:

I dont know if that has something to do with the brackets i use or the format of the variables. U have any tips for that?

[Benedikt Skurk]

Ok i got it..

But the last problem i have is that he doesnt transfer the column headers.

so for example first column header is PE EN Neuruppin_1 and second header is PE EN Wittst_3

[Scott MacKenzie]

To transfer the variable names, an extra line is needed...

newtable.Properties.VariableNames{j} = VarNames{i};

I added this line in the answer.

[Benedikt Skurk]

Thanks alot !

[Vlatko Milic]

Hi @Scott MacKenzie,

I have a similar problem but cannot manage to solve it. The table I am working with consists of eight columns.Each column has a unique vairable names, but between position 5 and 10 in the variable names, 2 columns have the same variables. Moreover, I want't to create four new tables (with the two matching columns) based on the original table with 8 columns. I have watched your code for inspiration but cannot manage the code to work according to my wishes, see below for code.

I'm helpful for any advice.

names = table.Properties.VariableNames;

matchVals = {'11111', '22222','33333','44444'}; %variable names i want to match
% 
columns=width(table) % 8 columns in total
%%
j=1;

for i=1:columns

if contains(names{i}, matchVals)   
        newtable(:,j) =table(:,i);
        newtable.Properties.VariableNames{j} = names{i};
       newtable.Properties.VariableNames{:,j} = names{i};
        j = j + 1; 
        
end   
end