conda create environment ResolvePackageNotFound when pip is successful

Question

I am trying to create a conda environment using the following environment.yml file:

conda env create -n med -f environment.yml

File contents:

name: med

channels: 
  - defaults
  - conda-forge

dependencies: 
  - python=3.8
  - batchgenerators==0.23
  - pandas==1.1.5
  - SimpleITK==2.2.1
  - tensorboard==2.11.0
  - tqdm
  - pip
  - pip: 
    - --extra-index-url https://download.pytorch.org/whl/cu117
    - torch==1.13.1+cu117
    - torchvision==0.14.1+cu117

The setup fails with:

ResolvePackageNotFound:

- batchgenerators

If I delete batchgenerators from the yml file, create the environment, conda activate it and try pip install batchgenerators - it is successful.

Further, using pip also works

conda create -n med 
conda activate med
pip install -r requirements.txt

batchgenerators==0.23
pandas==1.1.5
SimpleITK==2.2.1
tensorboard==2.11.0
torch==1.13.1+cu117
torchvision==0.14.1+cu117
tqdm

Any suggestions to make conda work directly? Thanks, Bogdan

Answer 1

Thanks to @griko. Adding batchgenerators to the yml file fixed the issue because the package is available on pypi but not in conda defaults or conda forge.

- pip: 
  - --extra-index-url https://download.pytorch.org/whl/cu117
  - torch==1.13.1+cu117
  - torchvision==0.14.1+cu117
  - batchgenerators==0.23