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Can you help me with this memoization simple example?

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From: mk1853...@gmail.com (marc nicole)
Newsgroups: comp.lang.python
Subject: Can you help me with this memoization simple example?
Date: Sun, 31 Mar 2024 01:09:43 +0100
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by: marc nicole - Sun, 31 Mar 2024 00:09 UTC

I am creating a memoization example with a function that adds up / averages
the elements of an array and compares it with the cached ones to retrieve
them in case they are already stored.

In addition, I want to store only if the result of the function differs
considerably (passes a threshold e.g. 500000 below).

I created an example using a decorator to do so, the results using the
decorator is slightly faster than without the memoization which is OK, but
is the logic of the decorator correct ? anybody can tell me ?

My code is attached below:

import time

def memoize(f):
cache = {}

def g(*args):
if args[1] == "avg":
sum_key_arr = sum(list(args[0])) / len(list(args[0]))
elif args[1] == "sum":
sum_key_arr = sum(list(args[0]))
if sum_key_arr not in cache:
for (
key,
value,
) in (
cache.items()
): # key in dict cannot be an array so I use the sum of the
array as the key
if (
abs(sum_key_arr - key) <= 500000
): # threshold is great here so that all values are
approximated!
# print('approximated')
return cache[key]
else:
# print('not approximated')
cache[sum_key_arr] = f(args[0], args[1])
return cache[sum_key_arr]

return g

@memoize
def aggregate(dict_list_arr, operation):
if operation == "avg":
return sum(list(dict_list_arr)) / len(list(dict_list_arr))
if operation == "sum":
return sum(list(dict_list_arr))
return None

t = time.time()
for i in range(200, 15000):
res = aggregate(list(range(i)), "avg")

elapsed = time.time() - t
print(res)
print(elapsed)

Kill Ugly Processor Architectures -- Karl Lehenbauer

devel / comp.lang.python / Can you help me with this memoization simple example?

Subject	Author
Can you help me with this memoization simple example?	marc nicole