Example 1: Using a for loop
The content of the file my_file.txt is
honda 1948 mercedes 1926 ford 1903
Source Code
def file_len(fname):
with open(fname) as f:
for i, l in enumerate(f):
pass
return i + 1
print(file_len("my_file.txt"))
Output
3
Using a for loop, the number of lines of a file can be counted.
- Open the file in read-only mode.
- Using a for loop, iterate through the object
f. - In each iteration, a line is read; therefore, increase the value of loop variable after each iteration.
Example 2: Using list comprehension
num_of_lines = sum(1 for l in open('my_file.txt'))
print(num_of_lines)
Output
3
- Open the file in read-only mode.
- Using a for loop, iterate through
open('my_file.txt'). - After each iteration, return 1.
- Find the sum of the returned values.