return_maps_only arg in sparse_quantize

[matteo-st]

Describe the bug
A clear and concise description of what the bug is.

The return_maps_only argument in sparse_quantize function does not seem to work as expected. If labels are used, the function return the tuple (discrete_coordinates[unique_map], features[unique_map], labels[unique_map], unique_map) but we expect just unique_map.

• Please complete all sections of this template if applicable. For installation, you must report the environment. Otherwise, your issue will be closed automatically.

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To Reproduce
Steps to reproduce the behavior. If the code is not attached and cannot be reproduced easily, the bug report will be closed without any comments.

• a minimally reproducible code.

python -c "import MinkowskiEngine as ME;import numpy as np; coords = np.array([[1,2,3], [4,5,6]]); feats = np.array([[1,1,1], [2,2,2]]);labels = np.array([[1], [2]]); print(len(ME.utils.sparse_quantize(
coords,
feats,
labels,
return_index=True,
return_maps_only=True, # This argument does not work as expected
)))"

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Expected behavior
A clear and concise description of what you expected to happen.

We expect that the function returns only unique_map, not a tuple of length 4.

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Desktop (please complete the following information):

• OS: Debian GNU/Linux 11 (bullseye)
• Python version: 3.8
• Pytorch version: 2.1.1
• CUDA version: 11.8
• NVIDIA Driver version: 12.0
• Minkowski Engine version 0.5.4

python -c "import MinkowskiEngine as ME; ME.print_diagnostics()

"
==========System==========
Linux-5.10.0-28-cloud-amd64-x86_64-with-glibc2.10
cat: /etc/lsb-release: No such file or directory
3.8.19 | packaged by conda-forge | (default, Mar 20 2024, 12:47:35)
[GCC 12.3.0]
==========Pytorch==========
2.1.1
torch.cuda.is_available(): True
==========NVIDIA-SMI==========
/usr/bin/nvidia-smi
Driver Version 525.105.17
CUDA Version 12.0
VBIOS Version 90.04.A7.00.01
Image Version G183.0200.00.02
GSP Firmware Version 525.105.17
==========NVCC==========
/usr/local/cuda/bin/nvcc
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2022 NVIDIA Corporation
Built on Wed_Sep_21_10:33:58_PDT_2022
Cuda compilation tools, release 11.8, V11.8.89
Build cuda_11.8.r11.8/compiler.31833905_0
==========CC==========
/usr/bin/c++
c++ (Debian 10.2.1-6) 10.2.1 20210110
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

==========MinkowskiEngine==========
0.5.4
MinkowskiEngine compiled with CUDA Support: True
NVCC version MinkowskiEngine is compiled: 11080
CUDART version MinkowskiEngine is compiled: 11080

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Additional context
Add any other context about the problem here.

[Vanessa-F]

Hi, how do you successfully installedMinkowski Engine ? I tried pip install, conda install and python local install and all failed.
When using pip install, it shows ERROR: Could not build wheels for MinkowskiEngine, which is required to install pyproject.toml-based projects

[EvgenyUgolkov]

@Vanessa-F Hello! I have the same issue. Did you manage to solve it? If yes, could you tell me, what was the problem?