How to delete the header of the 1st line of .txt

Hello, I would like to ask a question. I have multiple .txt files that I want to merge in vertical manner. the format of these .txt files is the attached file

(1 header & 1 line with numbers)

I am using the commands:

clc
clear

filename1 = ['19*.txt'];%filename
fid_t=fopen(filename1,'r')    
fid_p = fopen('final3.txt','w'); % writing file id
% if fid_p < 0, error('Cannot open file for writing.'); end
x = dir ('19*.txt');
for i = 1:length(x)
    filename1 = x(i).name;  %filename
    fid_t = fopen(filename1, 'r');%open it and pass id to fscanf (reading file id)
    if fid_t < 0, error('Cannot open file for reading.'); end
    data = fread(fid_t, inf, '*char');%read data
    fwrite(fid_p, data, 'char');%print data in File_all
    fclose(fid_t);% close reading file id
    
end

but the point is that I would like not to take into account the headers of all the .txt files.

How can I make it?

Answer 1

[Karim]

You could try it via the read and write table functions

% set the number of variables
opts = delimitedTextImportOptions("NumVariables", 9);

% start from second row
opts.DataLines = [2, Inf];

% use tab as delimiter 
opts.Delimiter = "\t";

% Specify column names and types
opts.VariableNames = ["DATE_EE", "SIZE", "LATITUDE", "LONGTITUDE", "LAT", "LON", "COUNT", "MAX_VALUE", "MIN_VALUE"];
opts.VariableTypes = ["double", "double", "double", "double", "double", "double", "double", "double", "double"];

% Specify file level properties
opts.ExtraColumnsRule = "ignore";
opts.EmptyLineRule = "read";

% read all files
AllFiles = dir('19*.txt');
for i = 1:length(AllFiles)
    tmpData = readtable(AllFiles(i).name, opts);
    if i == 1
        AllData = tmpData;
    else
        AllData = vertcat(AllData,tmpData);
    end
end

% write output file
writetable(AllData, "final.txt",'Delimiter','\t') 

[Ivan Mich]

Thank you, but I am sorry the final.txt file shows me NaN values for the numbers after the header. so it is not working...

[Karim]

Do you use different headers for the different files?

Can you upload your final.txt?

[Ivan Mich]

Yes I want to use different headers. I am uploading one input and the final .txt

[Karim]

ok the code i provided was based using the assumption of the header you showed in you initial example text file. If you want to use different headers you need to modife the

opts.VariableNames

variable in the routine so that it contains the correct variables.

for your new example this would be

opts.VariableNames = ["DATE_EARTHUAKE","Magnitude","lat_epicenter","lon_epicenter","macroseismic_lat","macroseismic_lon","Distance_Between_Epicenters","Macroseismic_Magnitude_IDPS_lt8","Macroseismic_magnitude_allIDPS"];

Alternatively, you can find some code below that doesn't look at the headers. It just skips the first line and merges the rest of the lines into one big file. However, if you use this, keep in mind that this code does not look at the order or names in the header. If your different files use a different ordering they will be concateiate wrongly.

% read all files
AllFiles = dir('19*.txt');
AllData = char('');
for i = 1:length(AllFiles)
    tmpData = fileread(AllFiles(i).name);
    strtIdx = regexp(tmpData,'\n');  
    AllData = [AllData tmpData(strtIdx(1)+1:end-1)];
end

fid_out = fopen("final.txt",'wt+');
fprintf(fid_out, '%s',AllData);
fclose(fid_out);