Move to dependency groups approach for pip installs

.github/workflows/build_docs.yml

@@ -60,7 +60,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install ford
+          pip install --group docs
 
       - name: Build docs with FORD
         run: ford FTorch.md
@@ -109,7 +109,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install ford
+          pip install --group docs
 
       - name: Build docs with FORD
         run: ford FTorch.md

.github/workflows/preprocessing.yml

@@ -45,7 +45,7 @@ jobs:
           python-version: '3.13'  # Use 3.13 as no PyTorch wheels for 3.14 yet.
 
       - name: Install fypp, the Fortran pre-processor
-        run: pip install fypp
+        run: pip install --group preproc
 
       - name: Check ftorch_tensor.fypp matches ftorch_tensor.f90
         run: |

.github/workflows/static_analysis.yml

@@ -65,7 +65,7 @@ jobs:
           python -m pip install --upgrade pip
           python -m venv ../ftorch_venv
           . ../ftorch_venv/bin/activate
-          pip install .[dev] --extra-index-url https://download.pytorch.org/whl/cpu
+          pip install . --extra-index-url https://download.pytorch.org/whl/cpu --group lint
 
       # Run CMake build to get compile commands for clang
       - name: FTorch CMake

.github/workflows/test_suite_macos_cpu_clang.yml

@@ -81,7 +81,7 @@ jobs:
           python -m pip install --upgrade pip
           python -m venv ftorch
           . ftorch/bin/activate
-          pip install . --extra-index-url https://download.pytorch.org/whl/cpu
+          pip install . --extra-index-url https://download.pytorch.org/whl/cpu --group test
 
       - name: Install gfortran and OpenMPI
         # Install from source to avoid compiler mismatch between gfortran versions

.github/workflows/test_suite_ubuntu_cpu_gnu.yml

@@ -122,7 +122,7 @@ jobs:
           python -m pip install --upgrade pip
           python -m venv ftorch
           . ftorch/bin/activate
-          pip install . --extra-index-url https://download.pytorch.org/whl/cpu
+          pip install . --extra-index-url https://download.pytorch.org/whl/cpu --group test
 
       - name: Install OpenMPI
         run: |

.github/workflows/test_suite_ubuntu_cpu_intel.yml

@@ -66,7 +66,7 @@ jobs:
           python -m pip install --upgrade pip
           python -m venv ftorch
           . ftorch/bin/activate
-          pip install . --extra-index-url https://download.pytorch.org/whl/cpu
+          pip install . --extra-index-url https://download.pytorch.org/whl/cpu --group test
 
       - name: Install Intel tools
         uses: rscohn2/setup-oneapi@a5ae4e7697b9cd5dc8a616f94c1e56b87140999d

.github/workflows/test_suite_ubuntu_cuda_gnu.yml

@@ -74,7 +74,7 @@ jobs:
           . ftorch/bin/activate
           # CUDA v12.9 chosen as latest supported by PyTorch
           # Check this is <= what GPU-runner has installed (backwards compatible)
-          pip install . --extra-index-url https://download.pytorch.org/whl/cu129
+          pip install . --extra-index-url https://download.pytorch.org/whl/cu129 --group test
 
       - name: Install cmake and NVIDIA dev toolkit
         run: |

.github/workflows/test_suite_windows_cpu_intel.yml

@@ -65,7 +65,7 @@ jobs:
           pip install --upgrade pip
           python -m venv ftorch
           call ftorch\Scripts\activate
-          pip install .
+          pip install . --group test
 
       - name: Build FTorch
         shell: cmd

codespace/build_FTorch.sh

@@ -9,7 +9,7 @@
 python3 -m venv venv
 # shellcheck source=/dev/null
 source venv/bin/activate
-pip install . --extra-index-url https://download.pytorch.org/whl/cpu
+pip install . --extra-index-url https://download.pytorch.org/whl/cpu --group examples
 
 # Extract the location of the installed packages in the venv
 # This is typically `FTorch/build/venv/lib/python3.xx/site-packages/`

examples/01_Tensor/README.md

@@ -24,7 +24,7 @@ To run this example requires:
 ## Running
 
 To run this example, first install FTorch as described in the main
-documentation.
+documentation, making use of the `examples` dependency group.
 
 To compile the Fortran code, using the included `CMakeLists.txt`, execute the
 following code:

examples/02_SimpleNet/README.md

@@ -30,13 +30,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation.
-Then from this directory create a virtual environment and install the necessary Python
-modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check that everything is working by running `simplenet.py`:
 ```

examples/03_ResNet/README.md

@@ -26,13 +26,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation.
-Then from this directory create a virtual environment an install the neccessary Python
-modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check that everything is working by running `resnet18.py`:
 

examples/05_MultiIO/README.md

@@ -34,13 +34,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation. Then
-from this directory create a virtual environment and install the necessary
-Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check everything is working by running `multiionet.py`:
 ```

examples/06_Looping/README.md

@@ -66,13 +66,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation. Then
-from this directory create a virtual environment and install the necessary
-Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check everything is working by running `simplenet.py`:
 ```

examples/07_MultiGPU/README.md

@@ -26,12 +26,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation. Then from
-this directory create a virtual environment and install the necessary Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check that everything is working by running `simplenet.py`:
 ```

examples/08_MPI/CMakeLists.txt

@@ -28,9 +28,6 @@ if(NOT DEFINED ENV{VIRTUAL_ENV} AND NOT DEFINED ENV{CONDA_PREFIX})
   message(FATAL_ERROR "Please activate your virtualenv or conda environment")
 endif()
 
-# Install Python dependencies
-execute_process(COMMAND ${Python_EXECUTABLE} -m pip install mpi4py)
-
 # Fortran example
 add_executable(mpi_infer_fortran mpi_infer_fortran.f90)
 target_link_libraries(mpi_infer_fortran PRIVATE FTorch::ftorch)

examples/08_MPI/README.md

@@ -26,14 +26,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation. Then
-from this directory create a virtual environment and install the necessary
-Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-pip install mpi4py
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 You can check the network is set up correctly by running `simplenet.py`:
 ```

examples/09_Autograd/README.md

@@ -30,13 +30,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation.
-Then from this directory create a virtual environment and install the necessary
-Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 ### Tensor manipulation demo
 

examples/10_Optimizers/README.md

@@ -25,14 +25,8 @@ To run this example requires:
 
 ## Running
 
-To run this example install FTorch as described in the main documentation.
-Then from this directory create a virtual environment and install the necessary
-Python modules:
-```
-python3 -m venv venv
-source venv/bin/activate
-pip install -r requirements.txt
-```
+To run this example, first install FTorch as described in the main
+documentation, making use of the `examples` dependency group.
 
 Run the Python version of the demo with
 ```

pages/developer/developer.md

@@ -23,11 +23,14 @@ expected for submissions.
 ### Developer requirements
 
 Development tools for [pre-processing](#fortran-source-and-fypp),
-[code styling](#code-style) etc. are pip-installable using the
+[code styling](#code-style) etc. are pip-installable using the `dev` dependency
+group in the
 [pyproject.toml file](https://github.com/Cambridge-ICCS/FTorch/blob/main/pyproject.toml):
 ```sh
-pip install .[dev]
+pip install . --group dev
 ```
+This pulls in the packages in the `docs`, `lint`, `preproc`, and `test`
+dependency groups, which can also be used individually.
 
 In order to streamline the process of uploading we provide a pre-commit hook in
 [`.githooks/pre-commit`](https://github.com/Cambridge-ICCS/FTorch/blob/main/.githooks/pre-commit).

pages/installation/general.md

@@ -35,14 +35,20 @@ For instructions on how to install PyTorch, TorchVision, and NumPy, see the
 If LibTorch is not installed then FTorch requires PyTorch to be installed.
 FTorch's `pt2ts` utility script has PyTorch as a hard requirement, as well as
 the `ftorch_utils` Python module included in the FTorch repo. To install
-PyTorch, `ftorch_utils`, and the additional dependencies (TorchVision and NumPy)
-of FTorch's examples suite, run
+PyTorch and `ftorch_utils`, run
 ```sh
 pip install . --extra-index-url <pytorch-wheel-download-url>
 ```
 where `<pytorch-wheel-download-url>` is determined based on the
 [matrix](https://pytorch.org/get-started/locally/) on the PyTorch website.
 
+We recommend also installing the additional dependencies for FTorch's examples
+(TorchVision, NumPy, matplotlib, and mpi4py) in the same command. This can be
+achieved by including the `examples` dependency group, as follows:
+```sh
+pip install . --extra-index-url <pytorch-wheel-download-url> --group examples
+```
+
 If you don't want to install `ftorch_utils` then you can install FTorch's
 `torch` and `torchvision` dependencies using
 ```sh
@@ -51,10 +57,10 @@ pip install torch torchvision --index-url <pytorch-wheel-download-url>
 
 @note
 We recommend installing `torch` and `torchvision` in the same command such as
-would be done in the secon command above. Doing so ensures that they are
-configured in the same way. If you have installed the `ftorch_utils` module as
-in the first command above then there is no need to worry about this because
-they are both included as dependencies.
+would be done in the third command above. Doing so ensures that they are
+configured in the same way. If you have installed the `ftorch_utils` module with
+the `examples` dependency group as in the second command above then there is no
+need to worry about this because they are both included as dependencies.
 @endnote
 
 #### Additional dependencies of the test suite

pages/installation/gpu.md

@@ -28,9 +28,10 @@ HIP with a LibTorch binary.
 
 #### Installation using pip
 
-To install `ftorch_utils` and its dependencies with GPU support, use
+To install `ftorch_utils`, its dependencies, and the additional dependencies
+for the examples with GPU support, use
 ```sh
-pip install . --extra-index-url <pytorch-wheel-download-url>
+pip install . --extra-index-url <pytorch-wheel-download-url> --group examples
 ```
 or to install `torch` and `torchvision` directly use
 ```sh

pages/installation/systems.md

@@ -72,7 +72,7 @@ rem Activate the virtual environment
 call .ftorch\Scripts\activate
 
 rem Install dependencies (--extra-index-url not required on Windows)
-pip install .
+pip install . --group examples
 
 rem Enable output
 ECHO ON

pyproject.toml

@@ -28,26 +28,35 @@ keywords = [
 ]
 classifiers = [
 	"Development Status :: 5 - Production/Stable",
+  "Intended Audience :: Science/Research",
+  "License :: OSI Approved :: MIT License",
 	"Programming Language :: Fortran",
 	"Programming Language :: Python",
+  "Topic :: Scientific/Engineering",
 ]
-dependencies = [
-  "matplotlib",
-  "numpy",
-  "torch",
-  "torchvision",
-]
+dependencies = ["torch"]
 
-[project.optional-dependencies]
-dev = [
+[dependency-groups]
+examples = ["matplotlib", "mpi4py", "numpy", "torchvision"]
+test = [
+  "pytest",
+  {include-group = "examples"},
+]
+docs = ["ford>=7.0.13"]
+lint = [
   "clang-format==19.1.3",
   "clang-tidy==19.1.0",
   "cmakelang",
-  "ford>=7.0.13",
   "fortitude-lint==0.7.0",
-  "fypp==3.2",
   "ruff==0.7.3",
 ]
+preproc = ["fypp==3.2"]
+dev = [
+  {include-group = "docs"},
+  {include-group = "lint"},
+  {include-group = "preproc"},
+  {include-group = "test"},
+]
 
 [project.scripts]
 pt2ts = "ftorch_utils.pt2ts:main_cli"