How to delete file if if have contain wrong value

Hi,

I have 700 ".txt" file that contain longitude and latitude. I want to keep data which have longitude 136<=long<=146, latitude 34<=lat<=41 and delete the other.

Does anyone have an idea how to do this? I have wrote the code, but it still return error.

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inputfolder = 'K:\Geonet data_2011\indata';
outputfolder = 'K:\Geonet data_2011\outdata';
numfiles = 1243;
%mydata = cell (1, numfiles);

for k = 1:numfiles
    inputfile = sprintf ('point%d.txt', inputfolder, k);
    data {k} = importdata (inputfile);
    x = load (inputfile);
    lat = x (:,8);
    long = x (:,9);

    if (lat<=41 && lat>=34)
       if (long<=146 && long>=136)
        inputfile = [];
       end
    end

    outputfile = sprintf ('%6d.11.pos' , outputfolder, k);
    save (outputfile, '%6d.11.pos')

[Image Analyst]

Please clarify. Do you want to delete a file (like it says in your subject line), or keep/save a file (like it says in the body of your message), or both?

[hidayat]

I want to delete a file which have a longitude and latitude value greater or lower than constrain value (as I write below) and keep the file if the file has value within the constrain value.

 if (lat<=41 && lat>=34)
       if (long<=146 && long>=136)

Do you have any suggestion for me? thank you in advance.

Answer 1

[Voss]

inputfolder = 'K:\Geonet data_2011\indata';
outputfolder = 'K:\Geonet data_2011\outdata';
numfiles = 1243;

for k = 1:numfiles
    
    inputfile = fullfile(inputfolder,sprintf('point%d.txt',k));
    
    % x = readmatrix(inputfile);
    x = load(inputfile);
    
    lat = x(:,8);
    long = x(:,9);
    
    to_keep = long >= 136 & long <= 146 & lat >= 34 & lat <= 41;
    x = x(to_keep,:);
    
    outputfile = fullfile(outputfolder,sprintf('%6d.11.pos',k));
    
    % writematrix(x,outputfile);
    save(outputfile,'x','-ascii');
    
end

readmatrix and writematrix (since R2019a) are preferred over load and save.