Merge pull request #108 from TileDB-Inc/ihn/add-utils

Add vector_search.utils

Author: Shelnutt2

apis/python/src/tiledb/vector_search/__init__.py

@@ -1,3 +1,4 @@
+from . import utils
 from .index import FlatIndex, IVFFlatIndex
 from .ingestion import ingest
 from .module import load_as_array
@@ -29,4 +30,5 @@
     "ivf_index_tdb",
     "array_to_matrix",
     "partition_ivf_index",
+    "utils"
 ]

apis/python/src/tiledb/vector_search/utils.py

@@ -0,0 +1,36 @@
+import tiledb
+import numpy as np
+import io
+
+def _load_vecs_t(uri, dtype, ctx_or_config=None):
+  with tiledb.scope_ctx(ctx_or_config) as ctx:
+      dtype = np.dtype(dtype)
+      vfs = tiledb.VFS(ctx.config())
+      with vfs.open(uri, "rb") as f:
+          d = f.read(-1)
+          raw = np.frombuffer(d, dtype=np.uint8)
+          ndim = raw[:4].view(np.int32)[0]
+
+          elem_nbytes = int(4 + ndim * dtype.itemsize)
+          if raw.size % elem_nbytes != 0:
+              raise ValueError(
+                  f"Mismatched dims to bytes in file {uri}: {raw.size}, elem_nbytes"
+              )
+          # take a view on the whole array as
+          # (ndim, sizeof(t)*ndim), and return the actual elements
+          #return raw.view(np.uint8).reshape((elem_nbytes,-1))[4:,:].view(dtype).reshape((ndim,-1))
+
+          if dtype != np.uint8:
+              return raw.view(np.int32).reshape((-1,ndim + 1))[:,1:].view(dtype)
+          else:
+              return raw.view(np.uint8).reshape((-1,ndim + 1))[:,1:].view(dtype)
+          #return raw
+
+def load_ivecs(uri, ctx_or_config=None):
+  return _load_vecs_t(uri, np.int32, ctx_or_config)
+
+def load_fvecs(uri, ctx_or_config=None):
+  return _load_vecs_t(uri, np.float32, ctx_or_config)
+
+def load_bvecs(uri, ctx_or_config=None):
+  return _load_vecs_t(uri, np.uint8, ctx_or_config)