Python-read-file

Some examples of reading a file with Python:

Without any additional python packages or modules

with open('test.txt', 'r') as file:
lines = file.readlines()
print(lines[9]) # Print the 10th line
print(lines[0:3]) # Print the first three lines

with open('test.txt', 'r') as file:
specified_lines = [0, 7, 11]
for pos, line in enumerate(file):
if pos in specified_lines:
print(line.strip())

pip install linecache

import linecache
line = linecache.getline('test.txt', 4)
print(line) # Print the 4th line

with open('test.txt', 'r') as file:
specified_lines = [0, 7, 11]
for pos, line in enumerate(file):
if pos in specified_lines:
print(line.strip())

Memory Usage: Using readlines() loads the entire file into memory, which may not be efficient for large files¹.
Performance: The linecache module is optimized for reading specific lines and is suitable for large files².