Merge pull request #390 from pyiron/atomsk4

Allow hcp 4-axes indices as well

pyiron_atomistics/atomistics/structure/factories/atomsk.py

@@ -52,9 +52,9 @@ def create(cls, lattice, a, *species, c=None, hkl=None):
         a_and_c = str(a) if c is None else f"{a} {c}"
         line = f"--create {lattice} {a_and_c} {' '.join(species)}"
         if hkl is not None:
-            if np.asarray(hkl).shape != (3, 3):
-                raise ValueError(f"hkl must have shape 3x3 if provided, not {hkl}!")
-            line += f" orient {' '.join(hkl[0])} {' '.join(hkl[1])} {' '.join(hkl[2])}"
+            if np.asarray(hkl).shape not in ( (3, 3), (3, 4) ):
+                raise ValueError(f"hkl must have shape 3x3 or 3x4 if provided, not {hkl}!")
+            line += "orient" + "  ".join("[" + "".join(map(str, a)) + "]" for a in hkl)
         # TODO: check len(species) etc. with the document list of supported phases
         self._options.append(line)
         return self
@@ -178,7 +178,7 @@ def create(self, lattice, a, *species, c=None, hkl=None):
             *species (list of str): chemical short symbols for the type of atoms to create, length depends on lattice
                                     type
             c (float, optional): third lattice parameter, only necessary for some lattice types
-            hkl (array of int, (3,3)): three hkl vectors giving the crystallographic axes that should point along the x,
+            hkl (array of int, (3,3) or (3,4)): three hkl vectors giving the crystallographic axes that should point along the x,
                                        y, z directions
 
         Returns: