segmentation fault (core dumped)

[duylncanawan]

I tried using this to create a file index for my project. here is my code:
import hnswlib
import numpy as np

Example vectors and paths

index_data_1 = np.random.rand(1280).astype('float32')
index_path_1 = '/path_1'

Add items to the index

indexer = hnswlib.Index(space='cosine', dim=1280)
indexer.add_items([index_data_1, index_path_1])
indexer.save_index('example_index.idx')

but the error occurs when indexer.add_items executes.

error: segmentation fault (core dumped)

i try python gdb to run and this is my error:

Thread 1 "python" received signal SIGSEGV, Segmentation fault.
0x00007ffff6e3ed67 in Index<float, float>::addItems(pybind11::object, pybind11::object, int, bool) ()
from /home/anaconda3/envs/flask/lib/python3.9/site-packages/hnswlib.cpython-39-x86_64-linux-gnu.so
(gdb) bt
#0 0x00007ffff6e3ed67 in Index<float, float>::addItems(pybind11::object, pybind11::object, int, bool) ()
from /home/anaconda3/envs/flask/lib/python3.9/site-packages/hnswlib.cpython-39-x86_64-linux-gnu.so
#1 0x00007ffff6e2aa6a in pybind11::cpp_function::initialize<pybind11::cpp_function::initialize<void, Index<float, float>, pybind11::object, pybind11::object, int, bool, pybind11::name, pybind11::is_method, pybind11::sibling, pybind11::arg, pybind11::arg_v, pybind11::arg_v, pybind11::arg_v>(void (Index<float, float>::)(pybind11::object, pybind11::object, int, bool), pybind11::name const&, pybind11::is_method const&, pybind11::sibling const&, pybind11::arg const&, pybind11::arg_v const&, pybind11::arg_v const&, pybind11::arg_v const&)::{lambda(Index<float, float>, pybind11::object, pybind11::object, int, bool)#1}, void, Index<float, float>, pybind11::object, pybind11::object, int, bool, pybind11::name, pybind11::is_method, pybind11::sibling, pybind11::arg, pybind11::arg_v, pybind11::arg_v, pybind11::arg_v>(pybind11::cpp_function::initialize<void, Index<float, float>, pybind11::object, pybind11::object, int, bool, pybind11::name, pybind11::is_method, pybind11::sibling, pybind11::arg, pybind11::arg_v, pybind11::arg_v, pybind11::arg_v>(void (Index<float, float>::)(pybind11::object, pybind11::object, int, bool), pybind11::name const&, pybind11::is_method const&, pybind11::sibling const&, pybind11::arg const&, pybind11::arg_v const&, pybind11::arg_v const&, pybind11::arg_v const&)::{lambda(Index<float, float>, pybind11::object, pybind11::object, int, bool)#1}&&, void ()(Index<float, float>, pybind11::object, pybind11::object, int, bool), pybind11::name const&, pybind11::is_method const&, pybind11::sibling const&, pybind11::arg const&, pybind11::arg_v const&, pybind11::arg_v const&, pybind11::arg_v const&)::{lambda(pybind11::detail::function_call&)#3}::_FUN(pybind11::detail::function_call) ()
from /home/anaconda3/envs/flask/lib/python3.9/site-packages/hnswlib.cpython-39-x86_64-linux-gnu.so
#2 0x00007ffff6e25342 in pybind11::cpp_function::dispatcher(_object, _object*, _object*) ()
from /home/anaconda3/envs/flask/lib/python3.9/site-packages/hnswlib.cpython-39-x86_64-linux-gnu.so
#3 0x00005555556d68f4 in cfunction_call (func=0x7ffff6e6ce50, args=, kwargs=) at /opt/conda/conda-bld/python-split_1654083059479/work/Objects/methodobject.c:543
#4 0x000055555569047f in _PyObject_MakeTpCall (tstate=0x55555591ec60, callable=0x7ffff6e6ce50, args=, nargs=, keywords=)
at /opt/conda/conda-bld/python-split_1654083059479/work/Objects/call.c:191
#5 0x000055555560a20f in _PyObject_VectorcallTstate (kwnames=, nargsf=, args=0x55555597b240, callable=0x7ffff6e6ce50, tstate=0x55555591ec60)
at /opt/conda/conda-bld/python-split_1654083059479/work/Include/cpython/abstract.h:116
#6 method_vectorcall (method=, args=0x55555597b248, nargsf=, kwnames=) at /opt/conda/conda-bld/python-split_1654083059479/work/Objects/classobject.c:53
#7 0x0000555555653300 in _PyObject_VectorcallTstate (kwnames=0x0, nargsf=, args=0x55555597b248, callable=0x7ffff6e78180, tstate=)

so what is my problem?
i use python 3.9

[kerighan]

same problem here

[duylncanawan]

same problem here

I found the reason,
The reason is due to the lack of init_index function, you must init_index before adding_items to avoid this error.
this way works for me.
indexer = hnswlib.Index(space='cosine', dim=1280)
indexer.init_index(max_elements = num_elements, ef_construction = 200, M = 16)