Chage commas with dots in sequential txt files?

I have many txt files named as follows:

filename_0.txt

filename_1.txt

filename_2.txt

....

each file has two colums and the numbers have comma as decimal separator. I have to import all the files sequentially in matlab. If the numbers had the dots as decimal separator I would not have any problems, since the following code successufully imports all the files sequentially:

numfiles = 1000; % <-- insert num of files

mydata = cell(1, numfiles);

for k = 1:numfiles

myfilename = sprintf('filename_%d.txt', k);

mydata{k} = importdata(myfilename);

end

However, with the commas as decimal separators the previous code does not import the numbers properly. Moreover, importdata doesn not allow the user to define the decimal separator. How can I do? I cannot manually substitute the commas with dots in 1000 files.

Thank you.

Answer 1

[Star Strider]

Without an example file, it is not possible to write specific code.

I would use the textscan (link) function to read them in as strings, use the strrep (link) function to convert the commas to periods, and then store the converted file. For example:

 for k = 1:numfiles
     myfilename = sprintf('filename_%d.txt', k);
     fidi = fopen(myfilename,'rt');
     mydatacomma = textscan(fidi, '%s%s', 'CollectOutput',1);
     fclose(fidi);
     mydatadot{k} = strrep(mydatacomma, ',',  '.');
 end

NOTE — Since I do not have one of your text files to experiment with, this is UNTESTED CODE. It should work, although you may need to modify it to work with your files.

The strrep function works correctly with cells:

d = {'1,234' '2,345'
     '4,319' '7,385'};
p = strrep(d, ',', '.')
p =

  2×2 cell array

    {'1.234'}    {'2.345'}
    {'4.319'}    {'7.385'}