main.cpp

#include "hnsw.h"

#include <algorithm>
#include <ctime>
#include <iostream>
#include <random>
#include <vector>
using namespace std;

void randomTest(int numItems, int dim, int numQueries, int K) {
	default_random_engine generator;
	uniform_real_distribution<double> distribution(0.0,1.0);
	vector<Item> randomItems;
	for (int i = 0; i < numItems; i++) {
		vector<double> temp(dim);
		for (int d = 0; d < dim; d++) {
			temp[d] = distribution(generator);
		}
		randomItems.emplace_back(temp);


	}
	
	random_shuffle(randomItems.begin(), randomItems.end());

	// construct graph
	HNSWGraph myHNSWGraph(100, 30, 30, 10, 2, 12);
	for (int i = 0; i < numItems; i++) {
		if (i % 10000 == 0) cout << i << endl;
		//cout<<"===="<<randomItems[i].values.size();
		//exit(0);
		myHNSWGraph.Insert(randomItems[i]);
	}
	
	double total_brute_force_time = 0.0;
	double total_hnsw_time = 0.0;

	cout << "START QUERY" << endl;
	int numHits = 0;
	for (int i = 0; i < numQueries; i++) {
		// Generate random query
		vector<double> temp(dim);
		for (int d = 0; d < dim; d++) {
			temp[d] = distribution(generator);
		}
		Item query(temp);

		// Brute force
		clock_t begin_time = clock();
		vector<pair<double, int>> distPairs;
		for (int j = 0; j < numItems; j++) {
			if (j == i) continue;
			distPairs.emplace_back(query.dist(randomItems[j]), j);
		}
		sort(distPairs.begin(), distPairs.end());
		total_brute_force_time += double( clock () - begin_time ) /  CLOCKS_PER_SEC;

		begin_time = clock();
		vector<int> knns = myHNSWGraph.KNNSearch(query, K);
		total_hnsw_time += double( clock () - begin_time ) /  CLOCKS_PER_SEC;

		if (knns[0] == distPairs[0].second) numHits++;
	}
	myHNSWGraph.printGraph();
	cout << numHits << " " << total_brute_force_time / numQueries  << " " << total_hnsw_time / numQueries << endl;
}

int main() {
	//cout<<"This";
	randomTest(1000, 4, 100, 5);
	return 0;
}