Reformat orca write_input

iodata/inputs/orca.py

@@ -18,14 +18,15 @@
 # --
 """Orca Input Module."""
 
+
 from typing import TextIO
 from string import Template
 
-import attr
+from .common import populate_fields
 
+from ..docstrings import document_write_input
 from ..iodata import IOData
 from ..periodic import num2sym
-from ..utils import angstrom
 
 __all__ = []
 
@@ -38,27 +39,18 @@
 *"""
 
 
+@document_write_input("ORCA", ['atnums', 'atcoords'],
+                      ['title', 'run_type', 'lot', 'obasis_name', 'spinmult', 'charge'])
 def write_input(f: TextIO, data: IOData, template: str = None):
     """Do not edit this docstring. It will be overwritten."""
-    # load IOData dict using attr.asdict because the IOData class uses __slots__
-    fields = attr.asdict(data, recurse=False)
-
-    # store atomic coordinates in angstrom
-    fields["atcoords"] = data.atcoords / angstrom
-
-    # replace None for default values
-    fields["title"] = data.title if data.title is not None else 'Input Generated by IOData'
-    fields["run_type"] = data.run_type if data.run_type is not None else 'energy'
-    # convert spin polarization to multiplicity
-    fields["spinmult"] = int(data.spinpol) + 1 if data.spinpol is not None else 1
-    fields["charge"] = int(data.charge) if data.nelec is not None else 0
+    # initialize a dictionary with fields to replace in the template
+    fields = populate_fields(data)
+    # set format-specific defaults
     fields["lot"] = data.lot if data.lot is not None else 'HF'
     fields["obasis_name"] = data.obasis_name if data.obasis_name is not None else 'STO-3G'
-
-    # convert run type to orca keywords
+    # convert run type to Orca keywords
     run_types = {"energy": "Energy", "freq": "Freq", "opt": "Opt"}
     fields["run_type"] = run_types[fields["run_type"].lower()]
-
     # generate geometry (in angstrom)
     geometry = []
     for num, coord in zip(fields["atnums"], fields["atcoords"]):
@@ -68,10 +60,8 @@ def write_input(f: TextIO, data: IOData, template: str = None):
             sym = f"{sym:>11}"  # adding an appropiate indentation
         geometry.append(f"{sym} {coord[0]:10.6f} {coord[1]:10.6f} {coord[2]:10.6f}")
     fields["geometry"] = "\n".join(geometry)
-
     # get template
     if template is None:
         template = default_template
-
     # populate files & write input
     print(Template(template).substitute(fields), file=f)