I'm getting an output data file of a program which looks like this, with more than one line for each time step: 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 7.9819E-06 1.7724E-02 2.3383E-02 3.0048E-02 3.8603E-02 4.9581E-02 5.6635E-02 4.9991E-02 3.9052E-02 3.0399E-02 .... I want to arrange it in ten columns I have made a Python script, using regular expressions to delete \n in the proper lines, but I think that there should be a simpler more elegant way to do it, here is my script: import re with open('inputfile', encoding='utf-8') as file1: datai=file1.read() dataf=re.sub(r'(?P<nomb>( \d\.\d\d\d\dE.\d\d){8})\n','\g<nomb>',datai) with open('result.txt',mode='w',encoding='utf-8') as resultfile: resultfile.write(datof) Thanks in advance