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Dictionaries and memory error. - jarrod0987 - Feb-23-2018
Is there a limit on how big a dictionary can be? I am trying to make one of all permutations of 0-9. If I do 0-8 it works fine. If I do 0-9 it gives a long pause them a Memory Error. How do I know what the limit is?
Is there another way to store this? a list was taking way way too long.
RE: Dictionaries and memory error. - buran - Feb-23-2018
why do you want to store all the possible permutations in memory? that is inefficient
RE: Dictionaries and memory error. - jarrod0987 - Feb-23-2018
(Feb-23-2018, 11:48 AM)buran Wrote: why do you want to store all the possible permutations in memory? that is inefficient
So what is the efficient way to be able to try all possible permutations for a variable until you get one that meets the criteria?
RE: Dictionaries and memory error. - buran - Feb-23-2018
use itertools.permutations(). Create iterator, consume it one permutation at a time to work with
this is brute force, so may be slow. there may be more efficient way to solve your problem (we don't know what your problem is)
RE: Dictionaries and memory error. - jarrod0987 - Feb-23-2018
(Feb-23-2018, 12:06 PM)buran Wrote: use itertools.permutations(). Create iterator, consume it one permutation at a time to work with
this is brute force, so may be slow. there may be more efficient way to solve your problem (we don't know what your problem is)
I seemed to have fixed my issue. I tried to create a list in program to store all the permutations but it was just taking forever. Almost instant now. Must have made a bug somewhere.
Anyways, it would be nice to know how to get itertools to feed the permutations into a variable one at a time. How do I do that?
RE: Dictionaries and memory error. - buran - Feb-23-2018
import itertools
for perm in itertools.permutations(range(5), 3):
print(perm)this will print all permutations with length 3 for numbers 0-4