In a tight loop (50-100ns/cycle) I am using a dict filled with randomly generated UInt64 keys. I think that they could be used directly in a hashmap, without hashing, so I am looking for a hashmap with a custom (here the identity) hash function. I hope to gain 2.5ns per cycle: julia> @btime hash(…

[image] tisztamo: I was not able to quickly find a package that allows that. Is there any? Just wrap your keys in a new type: struct MyKey val::UInt end Base.hash(a::MyKey, h::UInt) = xor(a.val, h) Base.(==)(a::MyKey, b::MyKey) = a.val == b.val

Dictionary with custom hash function

General Usage

stevengj Split this topic November 23, 2023, 1:37pm 8

3 posts were split to a new topic: Trouble defining hash/isequal for an interval type

Topic		Replies	Views
Fast hash for custom type General Usage question , performance , hash	10	868	September 17, 2021
Hash of Dict with custom type as keys General Usage dictionary	4	1325	September 20, 2021
Custom hash function in dict is very slow? Performance	3	888	April 20, 2021
Performance issues when working with dict Performance dictionary	11	1593	November 16, 2022
Really Fast Hash Set and Map Internals & Design	20	6041	August 29, 2018

Dictionary with custom hash function

Related topics