Splitting a String in a table once

The table provided in the picture is an example of the one i am working with (main table has over 4600 rows). I want/ need to split the first colum at the first white space. So that the output would be "ACTB" and "diff1 day 30" for example.

My internet research has brought me to the function

regexp()

with the parameters: (data,' ','split','once')

data = nameofthetable.columname

So far this hasn't worked for me, since i get the following error:

Error using regexp
The 'STRING' input must be either a char row vector, a cell array of char row vectors, or a
string array.

My question is can i even use this function with a table enviroment and if so how can i make it work and insert a new row? Or is the data type of the first colum wrong and not even a string?

I hope u can help me with this problem.

Thanks in advance.

Answer 1

[Walter Roberson]

I can tell from the way that the table displays that the entries are categorical() not character or string(). You would need to string() the variable before you can regex

[Marcel-Maximilian]

So if i understand it correctly " " always indicates a string right?

if i do string() it gives me a table with the string which is seperated from the other table. Is there a way to directly alter them in the original table? And if not how can i combine does two?

Thank you for your help! :)

[Walter Roberson]

S = ["ACTB (rep 1)"; "ACTB ipsc"];
CS = categorical(S);
T = table(S, CS)

T = 2×2 table
          S                CS     
    ______________    ____________

    "ACTB (rep 1)"    ACTB (rep 1)
    "ACTB ipsc"       ACTB ipsc   

Notice that inside tables, string() objects have the "" decoration around the entries, but categorical() objects have no decoration.

back = string(T.CS)

back = 2×1 string array
    "ACTB (rep 1)"
    "ACTB ipsc"

splits = regexp(back, '\s+', 'split', 'once')

splits = 2×1 cell array
    {["ACTB"    "(rep 1)"]}
    {["ACTB"    "ipsc"   ]}

You do not string() the table, you string() a variable in the table, and the result is a string array. You can insert the results into the table:

variety = categorical(cellfun(@(S) S(:,1), splits));
details = cellfun(@(S) S(:,2), splits);
T.variety = variety;
T.details = details;

T

T = 2×4 table
          S                CS         variety     details 
    ______________    ____________    _______    _________

    "ACTB (rep 1)"    ACTB (rep 1)     ACTB      "(rep 1)"
    "ACTB ipsc"       ACTB ipsc        ACTB      "ipsc"   

[Marcel-Maximilian]

Thank you for the help! :)