Add documentation to build GauXC (#14)

- add installation instructions for GauXC library
  - with OpenMP
  - with MPI
  - with CUDA
- list dependencies of GauXC (libtorch, ExchCXX, IntegratorXX, HDF5, HighFive, nlohmann_json, gau2grid, BLAS, ...)
- add instructions for obtaining checkpoints from Huggingface
- provide minimal example on how to use GauXC Skala library

Author: awvwgk

.github/workflows/examples.yml

@@ -0,0 +1,90 @@
+name: Examples
+
+on:
+  push:
+    branches: [ main, dev ]
+  pull_request:
+    branches: [ main, dev ]
+
+permissions:
+  contents: read
+
+jobs:
+  gauxc:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        toolchain: ["openmp", "mpi"]
+        gauxc: ["release", "main"]
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        path: skala
+
+    - name: Setup micromamba
+      uses: mamba-org/setup-micromamba@v1
+      with:
+        environment-file: skala/examples/cpp/gauxc_integration/environment-${{ matrix.toolchain }}.yml
+        environment-name: gauxc-dev
+        cache-environment: true
+        cache-downloads: true
+
+    - uses: actions/checkout@v4
+      with:
+        repository: wavefunction91/gauxc
+        ref: skala
+        path: gauxc
+
+    - name: Configure GauXC
+      if: ${{ matrix.gauxc == 'release' }}
+      run: >-
+        cmake
+        -B build_gauxc
+        -S gauxc
+        -G Ninja
+        -DGAUXC_ENABLE_OPENMP=${{ matrix.toolchain == 'openmp' }}
+        -DGAUXC_ENABLE_MPI=${{ matrix.toolchain == 'mpi' }}
+        -DGAUXC_ENABLE_CUDA=${{ matrix.toolchain == 'cuda' }}
+        -DGAUXC_ENABLE_ONEDFT=ON
+        -DBUILD_SHARED_LIBS=ON
+        -DCMAKE_INSTALL_PREFIX=$CONDA_PREFIX
+      shell: micromamba-shell {0}
+
+    - name: Build GauXC
+      if: ${{ matrix.gauxc == 'release' }}
+      run: cmake --build build_gauxc
+      shell: micromamba-shell {0}
+
+    - name: Install GauXC
+      if: ${{ matrix.gauxc == 'release' }}
+      run: cmake --install build_gauxc
+      shell: micromamba-shell {0}
+
+    - name: Configure project
+      run: >-
+        cmake
+        -B build_example
+        -S skala/examples/cpp/gauxc_integration
+        -G Ninja
+        -DSkala_GauXC_ENABLE_OPENMP=${{ matrix.toolchain == 'openmp' }}
+        -DSkala_GauXC_ENABLE_MPI=${{ matrix.toolchain == 'mpi' }}
+        -DSkala_GauXC_ENABLE_CUDA=${{ matrix.toolchain == 'cuda' }}
+        -DCMAKE_INSTALL_PREFIX=$CONDA_PREFIX
+      shell: micromamba-shell {0}
+
+    - name: Build project
+      run: cmake --build build_example
+      shell: micromamba-shell {0}
+
+    - name: Install project
+      run: cmake --install build_example
+      shell: micromamba-shell {0}
+
+    - name: Run example
+      run: >-
+         Skala
+         ./gauxc/tests/ref_data/onedft_he_def2qzvp_tpss_uks.hdf5
+         --model TPSS
+      shell: micromamba-shell {0}

docs/_static/bib/gauxc.bib

@@ -0,0 +1,47 @@
+@article{becke1988,
+  title={A multicenter numerical integration scheme for polyatomic molecules},
+  author={Becke, Axel D},
+  journal={The Journal of chemical physics},
+  volume={88},
+  number={4},
+  pages={2547--2553},
+  year={1988},
+  doi={10.1063/1.454033},
+  publisher={American Institute of Physics}
+}
+
+@article{mura1996,
+  title={Improved radial grids for quadrature in molecular density-functional calculations},
+  author={Mura, Michael E and Knowles, Peter J},
+  journal={The Journal of Chemical Physics},
+  volume={104},
+  number={24},
+  pages={9848--9858},
+  year={1996},
+  doi={10.1063/1.471749},
+  publisher={AIP Publishing}
+}
+
+@article{murray1993,
+  title={Quadrature schemes for integrals of density functional theory},
+  author={Murray, Christopher W and Handy, Nicholas C and Laming, Gregory J},
+  journal={Molecular Physics},
+  volume={78},
+  number={4},
+  pages={997--1014},
+  year={1993},
+  doi={10.1080/00268979300100651},
+  publisher={Taylor \& Francis}
+}
+
+@article{treutler1995,
+  title={Efficient molecular numerical integration schemes},
+  author={Treutler, Oliver and Ahlrichs, Reinhart},
+  journal={The Journal of Chemical Physics},
+  volume={102},
+  number={1},
+  pages={346--354},
+  year={1995},
+  doi={10.1063/1.469408},
+  publisher={American Institute of Physics}
+}

docs/conf.py

@@ -7,12 +7,18 @@
 extensions = [
     "myst_nb",
     "sphinx_book_theme",
+    "sphinx_design",
     "sphinx.ext.autodoc",
+    "sphinxcontrib.bibtex",
 ]
 
 nb_execution_timeout = 300  # 5 minutes, set to -1 for no timeout
 nb_merge_streams = True  # Merge multiple outputs from the same cell into one box
 
+bibtex_bibfiles = [
+    "_static/bib/gauxc.bib",
+]
+
 html_theme = "sphinx_book_theme"
 html_title = project
 html_logo = "_static/img/density.png"