MATLAB: How to read text file which has blanks in some columns

reading from text file

I have a text file in the following format :
    Algorithm   SNR   Q
     A          20    30
                25    32
                30    35
     B          20    32
                25    34
                30    36
I want to read this data of SNR and Q for 2 different algorithms so that i can plot SNR vs Q graph.
But the problem is that when I read this text file using Matlab functions (example textscan) , it doesn't read it correctly due to the empty spaces present in this text file in the column 'Algorithm'. For example: I tried to open this text file and read it and then display its contents :
fid = fopen('Test.txt'); 
C = textscan(fid,'%s %d %f');
fclose(fid);
celldisp(C);
The output of the above code is :
    C{1}{1} = Algorithm
    C{2} = []
    C{3} = []
If I remove the first column named 'Algorithm' from the text file and then read that file, then it works fine. But I am unable to read it correctly when that String column is also present. Can anyone please help me to know how can I read such data correctly from a text file. Thanks for your help in advance.

Best Answer

There are quite a few approaches. Here one example:
 fh = fopen('Swati.txt', 'r') ;
 fgetl(fh) ;                                           % Skip header.
 algs = {} ;
 data = {} ;
 while ~feof(fh)
    line = fgetl(fh) ;
    if all(line(1:12) == ' ')                          % No algo. name.
        content = textscan(line, '%f %f') ;            % Read only SNR and Q.
        data{end} = [data{end}; [content{:}]] ;        % Append to current data.
    else
        content = textscan(line, '%s %f %f') ;         % Read name, SNR, and Q.
        algs = [algs; content(1)] ;                    % Append to names.
        data = [data; {[content{2:3}]}] ;              % Create new data entry.
    end
 end
 fclose(fh) ;
Running this leads to:
 >> algs
 algs = 
    {1x1 cell}
    {1x1 cell}
 >> algs{1}
 ans = 
    'A' 
 >> data
 data = 
    [3x2 double]
    [3x2 double]
 >> data{1}
 ans =
    20    30
    25    32
    30    35
Please note that it is not the best possible approach/practice, but it is simple enough.
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