Adding a function to perform mesh generation only. Adding ability to combine...

Adding a function to perform mesh generation only. Adding ability to combine input filles in the PyGriffin.run method.

pygriffin/pygriffin.py

 from numbers import Integral
 from pathlib import Path
 import subprocess
+from tkinter import E
 from typing import Iterable
 import warnings
 
@@ -22,9 +23,10 @@ class PyGriffin:
     def __init__(self, input, mesh=None, n_procs=1):
         self.config = PyGriffinConfig()
         self.input = input
+        self.mesh = mesh
         self.n_procs = n_procs
 
-    def run(self, cwd=None, other_args=None):
+    def run(self, input=None, mesh=None, cwd=None, other_args=None):
         """
         Execute Griffin
 
@@ -41,6 +43,10 @@ class PyGriffin:
 
         cmd = []
 
+        # set custom values if requested in method call
+        input_file = self.input if input is None else input
+        mesh_file = self.mesh if mesh is None else mesh
+
         if self.n_procs > 1:
             if self.config.mpi_enabled:
                 cmd += ['mpirun', '-n', str(self.n_procs)]
@@ -52,7 +58,11 @@ class PyGriffin:
         # add griffin executable to command line
         cmd.append(str(self.config.griffin_exec))
 
-        cmd += ['-i', str(self.input)]
+        cmd += ['-i', str(input_file)]
+
+        # append the mesh file to the command if needed
+        if str(mesh_file).endswith('.i'):
+            cmd.append(str(mesh_file))
 
         if cwd is not None:
             cwd = Path(cwd)
@@ -72,6 +82,31 @@ class PyGriffin:
 
         return p.wait()
 
+    def generate_mesh(self, overwrite=False):
+        """
+        Generates the mesh for the griffin-problem if needed
+
+        Parameters
+        ----------
+        overwrite : bool
+            Overwrie the current mesh if needed (default False)
+
+        Returns
+        -------
+            Path to the mesh file
+        """
+        # if a mesh file was passed, no need to generate a new one
+        if str(self.mesh).endswith('.e'):
+            return self.mesh
+
+        # if a mesh input is set, generate the mesh file
+        if str(self.mesh).endswith('.i'):
+            name_parts = str(self.mesh).split('.')
+            name_parts[-1] = 'e'
+            mesh_name = '.'.join(name_parts)
+            self.run(input=self.mesh, other_args=['--mesh-only', mesh_name])
+            return Path(mesh_name).resolve().absolute()
+
     def __call__(self, cwd=None):
         return self.run(cwd)
 
@@ -91,6 +126,7 @@ class PyGriffin:
     @mesh.setter
     def mesh(self, mesh):
         cv.check_type('Griffin mesh', mesh, (str, Path))
+        self._mesh = mesh
 
     @property
     def xs(self):