STATIC VARIABLES

# graph type
MERGRAPH = "MERGRAPH"
HNSW = "HNSW"
NSG = "NSG"

# Methods for distance calculation
L2 = "L2"   # Euclidean distance
IP = "IP"   # Angle calculation
EUCLIDEAN = "L2"
ANGULAR = "IP"

Alaya.HNSW

__init__

def __init__(self,
            database: np.array,
            index_type: str=MERGRAPH,
            metric: str=L2,
            M: int=32,
            L: int=300,
            level: int=3,
            optimizer: int=os.cpu_count(),
            num_threads: int=os.cpu_count(),
            index_cache_dir: str="data/alaya_index",
            is_cache_index: bool=True,
            is_rebuild: bool=False
            ):

  """
  Args:
    database(np.array): 数据集, shape(n, dim)
    index_type(str): 索引类型, default=MERGRAPH
    metric(str): 距离度量, default=L2
    M(int): MERGRAPH的M参数, default=32
    L(int): MERGRAPH的L参数, default=300
    level(int): MERGRAPH的level参数, default=3
    optimizer(int): 调用优化器的线程数, default=os.cpu_count()
    num_threads(int): search时使用的线程数, default=os.cpu_count()
    index_cache_dir(str): 索引缓存目录, default="data/alaya_index"
    is_cache_index(bool): 是否缓存索引, default=True
    is_rebuild(bool): 是否重新构建索引, default=False

  Returns:
    None
  """

1. call alaya = Alaya(dataset=dataset, index_type=index_type) will create graph and save in ./data/index_index/

2. The name of the saved graph created isf'Alaya-{self.index_type}-{self.metric}-{self.M}-{self.__gene_md5()}'， e.g. Alaya-HNSW-L2-32-55ee368c93392e849c40de551b62fdb2

3. If you want to change the saved path, use index_cache_dir='/you/save/path'

4. If you don’t want to save the graph, use is_cache_index=False

5. If the graph is rebuilt regardless of whether it is cached or not, useis_rebuild=True

search

def search(self,
            query,
            ef: int=32,
            rerank_k: int=32,
            topk: int=10,
            is_trace: bool=False,
            save_json_dir: str='data/jsons'
            gt=None):
    """搜索topk个最近邻
    Args:
      query(np.array): 查询数据, shape=(n, dim)
      ef(int): ef参数, default=32
      rerank_k(int): 重排序的k, default=32
      topk(int): topk, default=10
      is_trace(bool): 是否记录搜索路径, default=False
      save_json_dir(str): 保存json的目录, default='data/jsons/
      gt(np.array): 真实的结果, default=None
    Returns:
      如果is_trace为False, 返回np.array: 返回topk个最近邻的id， shape=(n, topk)
      如果is_trace为True, 返回None, 并且将搜索路径保存到json文件
    """

Single point search

Multi point search

1. If need trace, set is_trace=True. Currently, the path is directly written into a JSON file

If not specified gt will be automatically calculated

The results of trace are saved by default in ./data/jsons/, you can change it by save_json_dir='/save/json/path/'

The content of the json file

{
  "metrics": {   # the recall of this predict
    "recall": 1.0
  },
  "searchGT": [  # the real top k ID
    255861,
    103225,
    166307,
    20817,
    225478,
    29077,
    227566,
    291213,
    20723,
    357105
  ],
  "searchRES": [  # the predict top k ID
    255861,
    103225,
    166307,
    20817,
    225478,
    29077,
    227566,
    291213,
    20723,
    357105
  ],
  "start_node": 1234,
  "traceInfo": [
    {
      "distance_s": 9.808282852172852,  # the distance from source to query(end point)
      "distance_t": 8.69454288482666,   # the distance from target to query(end point)
      "source": 0,
      "target": 435917,
      "value": 9.226316452026367.       # the distance from source to target
    },
    ...
  ]