NotImplementedError: Function convolution not implemented for backend numpy

[ewanmer20]

Before posting a bug report

• I have searched exisisting GitHub issues to make sure the issue does not already exist.

Expected behavior

Hello,
I have recently started using MrMustard and I tried to run this simple piece of code from the website to check if I installed it correctly. I attached a text file that contains all the dependencies of the python environment I have been using. To set up the environment, I just ran the following commands in the anaconda prompt:

conda create -n mrmustardtest python=3.9
conda activate mrmustardtest
pip install git+https://github.com/XanaduAI/MrMustard.git

Actual behavior

Error message

Reproduces how often

Every time

System information

name: mrmustardtest
channels:
  - defaults
dependencies:
  - ca-certificates=2023.12.12=haa95532_0
  - openssl=3.0.12=h2bbff1b_0
  - pip=23.3.1=py39haa95532_0
  - python=3.9.18=h1aa4202_0
  - setuptools=68.2.2=py39haa95532_0
  - sqlite=3.41.2=h2bbff1b_0
  - tzdata=2023d=h04d1e81_0
  - vc=14.2=h21ff451_1
  - vs2015_runtime=14.27.29016=h5e58377_2
  - wheel=0.41.2=py39haa95532_0
  - pip:
      - absl-py==2.0.0
      - astunparse==1.6.3
      - cachetools==5.3.2
      - certifi==2023.11.17
      - charset-normalizer==3.3.2
      - click==8.1.7
      - cloudpickle==3.0.0
      - colorama==0.4.6
      - commonmark==0.9.1
      - cycler==0.12.1
      - dask==2024.1.0
      - decorator==5.1.1
      - dm-tree==0.1.8
      - flatbuffers==23.5.26
      - fonttools==4.47.2
      - fsspec==2023.12.2
      - gast==0.5.4
      - google-auth==2.26.2
      - google-auth-oauthlib==1.2.0
      - google-pasta==0.2.0
      - grpcio==1.60.0
      - h5py==3.10.0
      - idna==3.6
      - importlib-metadata==7.0.1
      - julia==0.6.1
      - keras==2.15.0
      - kiwisolver==1.4.5
      - libclang==16.0.6
      - llvmlite==0.39.1
      - locket==1.0.0
      - markdown==3.5.2
      - markupsafe==2.1.3
      - matplotlib==3.5.0
      - ml-dtypes==0.2.0
      - mpmath==1.3.0
      - mrmustard==0.7.0.dev0
      - networkx==3.2.1
      - numba==0.56.4
      - numpy==1.23.5
      - oauthlib==3.2.2
      - opt-einsum==3.3.0
      - packaging==23.2
      - partd==1.4.1
      - pillow==10.2.0
      - protobuf==4.23.4
      - pyasn1==0.5.1
      - pyasn1-modules==0.3.0
      - pygments==2.17.2
      - pyparsing==3.1.1
      - python-dateutil==2.8.2
      - pyyaml==6.0.1
      - requests==2.31.0
      - requests-oauthlib==1.3.1
      - rich==10.15.1
      - rsa==4.9
      - scipy==1.8.0
      - setuptools-scm==8.0.4
      - six==1.16.0
      - sympy==1.12
      - tensorboard==2.15.1
      - tensorboard-data-server==0.7.2
      - tensorflow==2.15.0
      - tensorflow-estimator==2.15.0
      - tensorflow-intel==2.15.0
      - tensorflow-io-gcs-filesystem==0.31.0
      - tensorflow-probability==0.22.1
      - termcolor==2.4.0
      - thewalrus==0.19.0
      - tomli==2.0.1
      - toolz==0.12.0
      - tqdm==4.66.1
      - typing-extensions==4.9.0
      - urllib3==2.1.0
      - werkzeug==3.0.1
      - wrapt==1.14.1
      - zipp==3.17.0
prefix: C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest

Source code

from mrmustard.lab import *
results = Gaussian(3) << PNRDetector(efficiency = [0.9, 0.8], modes = [0,1])
print(results[2,3])

Tracebacks

Traceback (most recent call last):
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\math\backend_manager.py", line 105, in _apply
    attr = getattr(self.backend, fn)
AttributeError: 'BackendNumpy' object has no attribute 'convolution'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "c:\Users\em1120\qkdlab\Simulations\MrMustardSimulation\QKDProtocol.py", line 48, in <module>
    results = Gaussian(3) << PNRDetector(efficiency = [0.9, 0.8], modes = [0,1])
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\lab\detectors.py", line 97, in __init__
    self.recompute_stochastic_channel()
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\lab\detectors.py", line 126, in recompute_stochastic_channel
    math.convolve_probs_1d(
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\math\backend_manager.py", line 1455, in convolve_probs_1d
    return self.convolve_probs(prob, q)
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\math\backend_manager.py", line 1470, in convolve_probs
    return self.convolution(
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\math\backend_manager.py", line 430, in convolution
    return self._apply("convolution", (array, filters, padding, data_format))
  File "C:\Users\em1120\AppData\Local\anaconda3\envs\mrmustardtest\lib\site-packages\mrmustard\math\backend_manager.py", line 109, in _apply
    raise NotImplementedError(msg)
NotImplementedError: Function ``convolution`` not implemented for backend ``numpy``.

Additional information

No response

[sylviemonet]

Hi @ewanmer20 , I would suggest to add this change backend thing at the beginning of your code.
`import mrmustard.math as math

math.change_backend("tensorflow")`
Because now MrMustard supports two backends (Numpy and TensorFlow) and this is related to the backend TensorFlow originally.

One may experience a crash of code because of the Memory issue, so we also suggest to do this as a PNRDetector:
Gaussian(3) << Fock([2,3], modes=[0,1])

At the same time, our team is going to work on this issue and please let us know if you have more questions related.

[ziofil]

Adding in #517