refactor: moving lattice param calculations to before validator

matsciml/datasets/schema.py

@@ -776,21 +776,27 @@ def _exception_wrapper(self, exception: Exception):
             f"Data schema validation failed at sample {self.index}."
         ) from exception
 
+    @model_validator(mode="before")
+    @classmethod
+    def convert_lattice_and_parameters(cls, values: Any) -> Any:
+        lattice_params = values.get("lattice_parameters", None)
+        lattice_matrix = values.get("lattice_matrix", None)
+        if lattice_params is None and lattice_matrix is not None:
+            lattice_params = cell_to_cellpar(lattice_matrix)
+            values["lattice_parameters"] = lattice_params
+        if lattice_params is not None and lattice_matrix is None:
+            lattice_matrix = cellpar_to_cell(lattice_params)
+            values["lattice_matrix"] = lattice_matrix
+        return values
+
     @model_validator(mode="after")
     def coordinate_consistency(self) -> Self:
         """Sets fractional coordinates if parameters are available, and checks them"""
-        # convert lattice to lattice parameters if available
-        if self.lattice_matrix is not None and self.lattice_parameters is None:
-            self.lattice_parameters = cell_to_cellpar(self.lattice_matrix)
-        # convert lattice parameters to cell if available
-        if self.lattice_matrix is None and self.lattice_parameters is not None:
-            self.lattice_matrix = cellpar_to_cell(self.lattice_parameters)
-        # calculate fractional coordinates if we have lattice parameters
         if self.frac_coords is None and self.lattice_parameters is not None:
             self.frac_coords = cart_frac_conversion(
                 self.cart_coords, *self.lattice_parameters, to_fractional=True
             )
-        if self.frac_coords is not None:
+        if isinstance(self.frac_coords, NDArray):
             if self.frac_coords.shape != self.cart_coords.shape:
                 self._exception_wrapper(
                     ValueError(