vptree_test.js

const VPTreeFactory = require("vptree");
const crypto = require("crypto");

function hamming_distance(str1, str2) {
    let distance = 0;
    for (let i = 0; i < str1.length; i += 1) {
      if (str1[i] !== str2[i]) {
        distance += 1;
      }
    }
    return distance;
}

const phashes=[]
for (let i=0;i<500000;i++){
    let id = crypto.randomBytes(64).toString('hex');
    phashes.push(id)
}

console.log(`Array length: ${phashes.length}`)
console.time("vp-tree build")
const vptree=VPTreeFactory.build(phashes, hamming_distance)

console.timeEnd("vp-tree build")
console.time("vp-tree")
console.log(vptree.search("91189ee70f8a857dc8d66e2fc7059cd7c36c1dc320559b0970de0fe1321d65e6",10))
console.timeEnd("vp-tree")

console.time("for loop")
let qwe=[]
for (const phash of phashes){
    qwe.push({dist:hamming_distance("91189ee70f8a857dc8d66e2fc7059cd7c36c1dc320559b0970de0fe1321d65e6",phash),phash:phash})
}
qwe.sort((a,b)=>a.dist-b.dist)
qwe=qwe.slice(0,10)
console.timeEnd("for loop")

console.time("for loop w/o sorting")
qwe=[]
for (const phash of phashes){
    qwe.push({dist:hamming_distance("91189ee70f8a857dc8d66e2fc7059cd7c36c1dc320559b0970de0fe1321d65e6",phash),phash:phash})
}
console.timeEnd("for loop w/o sorting")
// console.log(qwe)