Measuring time II
As we discussed in the lectures, in the majority of cases, a list comprehension is faster than a for loop.
In this demonstration, you will see a case where a list comprehension and a for loop have so small difference in efficiency that choosing either method will perform this simple task instantly.
In the list words, there are random words downloaded from the Internet. We are interested to create another list called listlet in which we only keep the words that start with the letter b.
In case you are not familiar with dealing with strings in Python, each string has the .startswith() attribute, which returns a True/False statement whether the string starts with a specific letter/phrase or not.
Este exercício faz parte do curso
Writing Efficient Code with pandas
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Store the time before the execution
start_time = time.___()
# Execute the operation
letlist = [wrd for wrd in words if wrd.startswith('b')]
# Store and print the difference between the start and the current time
total_time_lc = time.time() - ___
print('Time using list comprehension: {} sec'.format(total_time_lc))