Question

I have two files. Call one file as a reference file. This file contains a list of strings each on a separate line. The other file is an input file. It also has strings on on each line.
I want to find the occurrence of each string from the reference file within the input file. This is my code

def count_line_occurrences(ref_list,input_list):
  line_counter = {}
  # Initialization
  for ref_line in ref_list:
    ref_line = ref_line.rstrip()
    line_counter[ref_line] = 0
  for input_line in input_list:
      input_line = input_line.rstrip()

  for ref_line in ref_list:
    #print ref_line
    for input_line in input_list:
      #print input_line
      if str(input_line).find(str(ref_line)) != -1:
        print 'found ' + ref_line
        line_counter[ref_line] += 1
  return line_counter

However it is not working.
Note – This is not a HW problem. But this is a part of a bigger task. Also, strangely, I have implemented this part in Perl and it is working fine. I want to shift the project to Python and I am having issues here. Thanks in advance for the help.

Answer 1

It sort of works for me. Calling your function like …

if __name__ == "__main__":
    x = count_line_occurrences(["a","b","c"],["c","c","b","a"])
    print x

prints out …

found a
found b
found c
found c
{'a': 1, 'c': 2, 'b': 1}

@Sumod … isn’t that the expected behavior ?

Edition after seeing @Sumod’s input data

So the problem with your input is that you are not cleaning correctly the trailing characters \t\n.

The following code works …

def count_line_occurrences(ref_list,input_list):
  line_counter = {}

  ref_list = map(lambda x: x.strip(" \t\n"),ref_list)
  input_list = map(lambda x: x.strip(" \t\n"),input_list)

  # Initialization
  for ref_line in ref_list:
    line_counter[ref_line] = 0

  for ref_line in ref_list:
    #print ref_line
    for input_line in input_list:
      #print input_line
      if str(input_line).find(str(ref_line)) != -1:
        print 'found ' + ref_line
        line_counter[ref_line] += 1
  return line_counter

notice that prior to the init of your counters I do the cleaning of both input lists with …

ref_list = map(lambda x: x.strip(" \t\n"),ref_list)
input_list = map(lambda x: x.strip(" \t\n"),input_list)

The string.strip function in python receives the characters I want to clean up.

For the input …

    ref_list = ['.Net Framework\n', '7-Zip\n', 'ACT DCP \n', 'ActivePerl \n', 'ActiveState Komodo Edit\n', 'ActiveTCL \n', 'Adobe Flash Player\n']
    input_list = ['7-Zip 4.57\t\n', 'WebEx\t\n', 'Adobe Acrobat Reader 8.0.0\t\n', 'Adobe Flash Player 10 ActiveX\t10.0.32.18\n']
    x = count_line_occurrences(ref_list,input_list)
    print x

I get …

{'ActiveState Komodo Edit': 0, '.Net Framework': 0, 'ACT DCP': 0, 'ActivePerl': 0, 'Adobe Flash Player': 1, '7-Zip': 1, 'ActiveTCL': 0}