change precision to n_decimals

gmso/formats/gro.py

@@ -103,7 +103,7 @@ def read_gro(filename):
 
 
 @saves_as(".gro")
-def write_gro(top, filename, precision=3, shift_coord=False):
+def write_gro(top, filename, n_decimals=3, shift_coord=False):
     """Write a topology to a gro file.
 
     The Gromos87 (gro) format is a common plain text structure file used
@@ -119,7 +119,7 @@ def write_gro(top, filename, precision=3, shift_coord=False):
         The `topology` to write out to the gro file.
     filename : str or file object
         The location and name of file to save to disk.
-    precision : int, optional, default=3
+    n_decimals : int, optional, default=3
         The number of sig fig to write out the position in.
     shift_coord : bool, optional, default=False
         If True, shift the coordinates of all sites by the minimum position
@@ -147,7 +147,7 @@ def write_gro(top, filename, precision=3, shift_coord=False):
             )
         )
         out_file.write("{:d}\n".format(top.n_sites))
-        out_file.write(_prepare_atoms(top, pos_array, precision))
+        out_file.write(_prepare_atoms(top, pos_array, n_decimals))
         out_file.write(_prepare_box(top))
 
 
@@ -166,7 +166,7 @@ def _validate_positions(pos_array):
     return pos_array
 
 
-def _prepare_atoms(top, updated_positions, precision):
+def _prepare_atoms(top, updated_positions, n_decimals):
     out_str = str()
     warnings.warn(
         "Residue information is parsed from site.molecule,"
@@ -226,8 +226,8 @@ def _prepare_atoms(top, updated_positions, precision):
         atom_id = atom_id % max_val
         res_id = res_id % max_val
 
-        varwidth = 5 + precision
-        crdfmt = f"{{:{varwidth}.{precision}f}}"
+        varwidth = 5 + n_decimals
+        crdfmt = f"{{:{varwidth}.{n_decimals}f}}"
 
         # preformat pos str
         crt_x = crdfmt.format(pos[0].in_units(u.nm).value)[:varwidth]