I have a list of words in a dictionary with the value = the repetition of the keyword but I only want a list of distinct words so I wanted to count the number of keywords. I
Some modifications were made on posted answer UnderWaterKremlin to make it python3 proof. A surprising result below as answer.
System specs:
import timeit
d = {x: x**2 for x in range(1000)}
#print (d)
print (len(d))
# 1000
print (len(d.keys()))
# 1000
print (timeit.timeit('len({x: x**2 for x in range(1000)})', number=100000)) # 1
print (timeit.timeit('len({x: x**2 for x in range(1000)}.keys())', number=100000)) # 2
Result:
1) = 37.0100378
2) = 37.002148899999995
So it seems that len(d.keys()) is currently faster than just using len().