added check for openmc version

README.md

@@ -6,6 +6,8 @@ A Python package for plotting the positions, directions or energy distributions
 
 # Installation
 
+You will need to have OpenMC version 0.14.0 or newer installed first.
+
 ```bash
 pip install openmc_source_plotter
 ```

src/openmc_source_plotter/core.py

@@ -9,8 +9,20 @@
 import openmc.lib
 import plotly.graph_objects
 
+import pkg_resources
+
+system_openmc_version = pkg_resources.parse_version(openmc.__version__)
+min_openmc_version = pkg_resources.parse_version("0.14.0")
+if system_openmc_version < min_openmc_version:
+    msg = (
+        "openmc_source_plotter requires openmc version 0.14.0 or above. "
+        f"You have openmc version {system_openmc_version} installed. "
+        "Please update the version of openmc installed"
+    )
+    raise ImportError(msg)
+
 
 def sample_initial_particles(self, n_samples: int = 1000, prn_seed: int = None):
 
     if isinstance(self, openmc.Model):
 
@@ -83,7 +95,7 @@
     e_values = [particle.E for particle in data]
 
     # Calculate pdf for source energies
     probability, bin_edges = np.histogram(e_values, bins=energy_bins, density=True)
 
     # scaling by strength
     if isinstance(self, openmc.SourceBase):