I am new to Python and I'm trying to optimize this code for large numbers. However I'm struggling to find an optimized way. If I run it as it is, it takes almost 4 minutes. I know it has something to do with loop and the max and randint function. I tried to use random.random as I read that is quicker but I got almost the same result. Can you think of a better way so it doesn't take that long?
from random import randint
def func(iters, n):
# Function to add max random numbers to a list.
l = [0]
for i in range(iters):
r = randint(0, n)
max_l = max(l)
if r > max_l:
l.append(r)
else:
l.append(max_l + 1)
return l
func(100000, 50)
a'r
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2 Answers 2
Yes as mentioned by @quamrana the last index of the list contains the max so just access instead of calculating it every time.
from random import randint
def func(iters, n):
#Function to add max random numbers to a list.
l = [0]
for i in range(iters):
r = randint(0, n)
max_l = l[-1]
if r > max_l:
l.append(r)
else:
l.append(max_l + 1)
return l
func(100000, 50)
answered May 16, 2020 at 10:43
Raghavendra Sugeeth
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1 Comment
a'r
On my system, this changed the runtime from ~50 seconds to <1 second.
You can try using random.choice function which is a bit faster:
from random import choice
def func(iters, n):
# Function to add max random numbers to a list.
l = [0]
max_l = 0
random_numbers = list(range(n))
for _ in range(iters):
r = choice(random_numbers)
if r > max_l:
l.append(r)
max_l = r
else:
l.append(max_l + 1)
max_l += 1
return l
print(func(100000, 50))
And also you don't need to calculate max every time. The last value you insert is always the max_l value.
answered May 16, 2020 at 10:50
Mushif Ali Nawaz
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Comments
lang-py
max_l = max(l)which you calculate each time round. Instead you have the information formax_lat the end of each loop.