在 python 中枚举 function 的打印元素出现问题

Question

This is a part of my python application code which is located in a for loop itself. It finds every file's name from another text file.

When I print i it prints the right line number every time. The problem is with the sen . When I print sen , it prints just a new line( \n ). Why doesn't it contain every line's content?

line_number=1
for line in open(relevant_docs_path, "r",encoding="utf8"):
  
  if line.rstrip('\n') == file_name:
    with open(relevant_docs_path) as fp:
      for i, sen in enumerate(fp):
        if i == line_number+1:
          print(sen)
    break
  else:
    line_number += 1 

and this is my text file(fp):

1.persian_query
7894.persian_poem 7895.persian_poem 7898.persian_poem 7899.persian_poem 7900.persian_poem

2.persian_query
7901.persian_poem 7902.persian_poem

3.persian_query
7901.persian_poem 7902.persian_poem

4.persian_query
7903.persian_poem

5.persian_query
7904.persian_poem 7905.persian_poem 7906.persian_poem 7907.persian_poem 7908.persian_poem 7909.persian_poem 7910.persian_poem 7911.persian_poem 7912.persian_poem 7913.persian_poem 7914.persian_poem 7915.persian_poem 7916.persian_poem 7917.persian_poem 7918.persian_poem 7919.persian_poem 7920.persian_poem 7921.persian_poem 7922.persian_poem 7923.persian_poem 7924.persian_poem

Answer 1

The main problem is that enumerate starts counting at 0 while line_number is initialized at 1. You need to either change line_number to 0 or use enumarate(..., start=1) .

Updated code:

line_number = 1
for line in open(relevant_docs_path, "r", encoding="utf8"):
  if line.rstrip('\n') == file_name:
    with open(relevant_docs_path) as fp:
      for i, sen in enumerate(fp, start=1):
        if i == line_number+1:
          print(sen)
    break
  else:
    line_number += 1