python - How to remove all lines in a file containing a specific character except for the first? -


i trying make script merges files in directory , remove unwanted lines in output file. lines want remove contain same string pattern , want remove first of lines (which first line in file). here how trying it:

import glob  # merge output files 1 file read_files = glob.glob('/home/user/results/script_tests/testresults/*.output')  open('mergedoutput.txt', 'r+b') outfile:     file in read_files:         open(file, 'r+b') infile:             outfile.write(infile.read())  print 'files merged.'            # remove header rows except row 1  final_output = open('finalmergedoutput.txt', 'r+b') open('mergedoutput.txt', 'r+b') file:     line in file:         if line == 0 , line.startswith('file'):             final_output.write(line)         elif line > 0 , not line.startswith('file'):              final_output.write(line)   print 'headers removed except on line 1.'

the merging part works pretty except lines seem copied in finalmergedoutput.txt. removal of lines removes lines starting file , not spare first...

does have elegant solution this?

for line in file iterates on actual content of file, not line numbers. since empty string greater 0, first condition can never e true , 2nd 1 (when .startswith(..) true...).

there many idioms of special handling of first item in list, pretty straight forward 1 minimal adjustments code:

for line_num,line in enumerate(file):     if line_num == 0 , line.startswith('file'):         final_output.write(line)     elif line_num > 0 , not line.startswith('file'):          final_output.write(line)

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