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#include "../../hnswlib/hnswlib.h"
typedef unsigned int docidtype;
typedef float dist_t;
int main() {
int dim = 16; // Dimension of the elements
int max_elements = 10000; // Maximum number of elements, should be known beforehand
int M = 16; // Tightly connected with internal dimensionality of the data
// strongly affects the memory consumption
int ef_construction = 200; // Controls index search speed/build speed tradeoff
int min_num_candidates = 100; // Minimum number of candidates to search in the epsilon region
// this parameter is similar to ef
int num_queries = 5;
float epsilon2 = 2.0; // Squared distance to query
// Initing index
hnswlib::L2Space space(dim);
hnswlib::HierarchicalNSW<dist_t>* alg_hnsw = new hnswlib::HierarchicalNSW<dist_t>(&space, max_elements, M, ef_construction);
// Generate random data
std::mt19937 rng;
rng.seed(47);
std::uniform_real_distribution<> distrib_real;
size_t data_point_size = space.get_data_size();
char* data = new char[data_point_size * max_elements];
for (int i = 0; i < max_elements; i++) {
char* point_data = data + i * data_point_size;
for (int j = 0; j < dim; j++) {
char* vec_data = point_data + j * sizeof(float);
float value = distrib_real(rng);
*(float*)vec_data = value;
}
}
// Add data to index
for (int i = 0; i < max_elements; i++) {
hnswlib::labeltype label = i;
char* point_data = data + i * data_point_size;
alg_hnsw->addPoint(point_data, label);
}
// Query random vectors
for (int i = 0; i < num_queries; i++) {
char* query_data = new char[data_point_size];
for (int j = 0; j < dim; j++) {
size_t offset = j * sizeof(float);
char* vec_data = query_data + offset;
float value = distrib_real(rng);
*(float*)vec_data = value;
}
std::cout << "Query #" << i << "\n";
hnswlib::EpsilonSearchStopCondition<dist_t> stop_condition(epsilon2, min_num_candidates, max_elements);
std::vector<std::pair<float, hnswlib::labeltype>> result =
alg_hnsw->searchStopConditionClosest(query_data, stop_condition);
size_t num_vectors = result.size();
std::cout << "Found " << num_vectors << " vectors\n";
delete[] query_data;
}
delete[] data;
delete alg_hnsw;
return 0;
}
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