Trip Destination Alternatives Preprocessor

activitysim/abm/models/trip_destination.py

@@ -60,6 +60,7 @@ class TripDestinationSettings(LocationComponentSettings, extra="forbid"):
     PRIMARY_DEST: str = "tour_leg_dest"  # must be created in preprocessor
     REDUNDANT_TOURS_MERGED_CHOOSER_COLUMNS: list[str] | None = None
     preprocessor: PreprocessorSettings | None = None
+    alts_preprocessor: PreprocessorSettings | None = None
     CLEANUP: bool
     fail_some_trips_for_testing: bool = False
     """This setting is used by testing code to force failed trip_destination."""
@@ -1245,6 +1246,7 @@ def run_trip_destination(
             state.filesystem, model_settings_file_name
         )
     preprocessor_settings = model_settings.preprocessor
+    alts_preprocessor_settings = model_settings.alts_preprocessor
     logsum_settings = state.filesystem.read_model_settings(
         model_settings.LOGSUM_SETTINGS
     )
@@ -1334,8 +1336,6 @@ def run_trip_destination(
     # returns a series of size_terms for each chooser's dest_zone_id and purpose with chooser index
     size_term_matrix = DataFrameMatrix(alternatives)
 
-    # don't need size terms in alternatives, just zone_id index
-    alternatives = alternatives.drop(alternatives.columns, axis=1)
     alternatives.index.name = model_settings.ALT_DEST_COL_NAME
 
     sample_list = []
@@ -1369,6 +1369,15 @@ def run_trip_destination(
                     trace_label=nth_trace_label,
                 )
 
+            if alts_preprocessor_settings:
+                expressions.assign_columns(
+                    state,
+                    df=alternatives,
+                    model_settings=alts_preprocessor_settings,
+                    locals_dict=locals_dict,
+                    trace_label=tracing.extend_trace_label(nth_trace_label, "alts"),
+                )
+
             if isinstance(
                 nth_trips["trip_period"].dtype, pd.api.types.CategoricalDtype
             ):

activitysim/abm/models/vehicle_allocation.py

@@ -259,6 +259,8 @@ def vehicle_allocation(
             choices.loc[choices["alt_choice"] == alt, "choice"] = choosers.loc[
                 choices["alt_choice"] == alt, alt
             ]
+
+        # set choice for non-household vehicle option
         choices.loc[
             choices["alt_choice"] == alts_from_spec[-1], "choice"
         ] = alts_from_spec[-1]

activitysim/core/interaction_sample.py

@@ -259,6 +259,15 @@ def _interaction_sample(
             sharrow_enabled=sharrow_enabled,
         )
 
+        alternatives = util.drop_unused_columns(
+            alternatives,
+            spec,
+            locals_d,
+            custom_chooser=None,
+            sharrow_enabled=sharrow_enabled,
+            additional_columns=["tdd", "origin_destination"],
+        )
+
     if sharrow_enabled:
         (
             interaction_utilities,

activitysim/core/interaction_sample_simulate.py

@@ -160,6 +160,15 @@ def _interaction_sample_simulate(
             sharrow_enabled=sharrow_enabled,
         )
 
+        alternatives = util.drop_unused_columns(
+            alternatives,
+            spec,
+            locals_d,
+            custom_chooser=None,
+            sharrow_enabled=sharrow_enabled,
+            additional_columns=["tdd", "origin_destination"],
+        )
+
     interaction_df = alternatives.join(choosers, how="left", rsuffix="_chooser")
     logger.info(
         f"{trace_label} end merging choosers and alternatives to create interaction_df"