Calculate SNAP descriptors

.ci_support/environment-lammps.yml

@@ -0,0 +1,4 @@
+channels:
+- conda-forge
+dependencies:
+- lammps =2023.11.21

.github/workflows/unittests.yml

@@ -46,6 +46,9 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
+    - name: Merge conda environment
+      if:  matrix.operating-system != 'windows-latest'
+      run: tail --lines=+4 .ci_support/environment-lammps.yml >> .ci_support/environment.yml
     - name: Setup Mambaforge
       uses: conda-incubator/setup-miniconda@v2
       with:

structuretoolkit/analyse/__init__.py

@@ -23,6 +23,11 @@
     get_voronoi_vertices,
 )
 from structuretoolkit.analyse.strain import get_strain
+from structuretoolkit.analyse.snap import (
+    get_snap_descriptor_names,
+    get_snap_descriptors_per_atom,
+    get_snap_descriptor_derivatives,
+)
 
 
 def get_symmetry(