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jweinst1 / 32bit_murmur_10mill.cpp
Last active January 12, 2026 04:48
hashmap for murmur3
#include <iostream>
#include <vector>
#include <unordered_map>
#include <random>
#include <chrono>
#include <cstdint>
// =======================================================
// MurmurHash3 x64 → 64-bit
// =======================================================
@jweinst1
jweinst1 / call_auction_trader.cpp
Created January 5, 2026 09:21
Call Auction implementation with traders
#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
struct Trader {
int id;
double cash;
int inventory;
};
@jweinst1
jweinst1 / lob_stocks.cpp
Created January 3, 2026 05:01
minimal LOB simulate
#include <iostream>
#include <map>
#include <deque>
#include <algorithm>
enum class Side { Buy, Sell };
struct Order {
Side side;
double price; // ignored for market orders
@jweinst1
jweinst1 / hamming_sep_dist.cpp
Last active December 26, 2025 22:52
and pop count of specific segments of bits for 8 bit dimension vectors
#include <array>
#include <cstdint>
#include <cstddef>
#include <cmath>
#include <cstdio>
#include <climits>
#include <vector>
#include <cassert>
#include <random>
#include <chrono>
@jweinst1
jweinst1 / hamming_centers.cpp
Created December 24, 2025 00:31
sorting bit sets of numbers based on hamming distance
#include <array>
#include <cstdint>
#include <cstddef>
#include <cmath>
#include <cstdio>
#include <climits>
#include <vector>
#include <cassert>
#include <random>
#include <chrono>
@jweinst1
jweinst1 / lzsort.cpp
Last active December 23, 2025 06:19
Automatic Sorting in Rust with bit RZ and LZ instructions
#include <array>
#include <cstdint>
#include <cstddef>
#include <cmath>
#include <cstdio>
#include <climits>
#include <vector>
#include <cassert>
#include <random>
#include <chrono>
@jweinst1
jweinst1 / automeantest.cpp
Created December 9, 2025 08:34
uses optimized popcount of integer series shifted right once to get very fast mean approximation
#include <array>
#include <cstdint>
#include <cstddef>
#include <cmath>
#include <cstdio>
#include <climits>
#include <vector>
#include <random>
#include <cassert>
@jweinst1
jweinst1 / bitsorter.cpp
Last active December 19, 2025 01:39
automatic bit sorting in C++
#include <array>
#include <cstdint>
#include <cstddef>
#include <cmath>
#include <cstdio>
#include <climits>
#include <vector>
#include <cassert>
#include <random>
#include <chrono>
@jweinst1
jweinst1 / murur3.rs
Created November 29, 2025 22:26
murmur3 in rust
pub fn murmur3_x64_64(data: &[u8], seed: u64) -> u64 {
let mut h1 = seed;
let mut h2 = seed;
const C1: u64 = 0x87c37b91114253d5;
const C2: u64 = 0x4cf5ad432745937f;
let mut i = 0;
let len = data.len();
while i + 16 <= len {
@jweinst1
jweinst1 / forward_back_context.py
Created November 16, 2025 00:01
forward and back contexts of a word
class WordContext(object):
def __init__(self, direction, terms):
self.direction = direction
self.terms = terms
def __repr__(self):
return f"{self.direction} - {self.terms}"
def make_context_list(seq, target):