Changing serialized migration parameters

Not every parameter can be changed after the creation of serialized files. The following overview is intended as high-level guidance for what changes can and cannot be made.

Migration_Model

  • ON-to-OFF: If you turn it off, there will be no human migration even if the serialized file had trips planned or people were waiting to return.

  • OFF-to-ON:

    • If the file was serialized with migration off, and you set the Migration_Model to FIXED_RATE_MIGRATION and set Migration_Pattern to SINGLE_ROUND_TRIPS/RANDOM_WALK_DIFFUSION, then the migration will work as expected.

    • If the file was serialized with migration off, and you set Migration_Pattern = WAYPOINTS_HOME, then the serialized people will be fixed at one waypoint. Newborns will get the value of Roundtrip_Waypoints, but not the serialized people.

Migration_Pattern

This cannot be serialized. Changing the value will change behavior but not in a guaranteed way. For example, if you change it from SINGLE_ROUND_TRIPS to WAYPOINTS_HOME, Roundtrip_Waypoints is always 1 for the people that were serialized. Newborns should get the new value.

Note that while the type of Migration_Pattern cannot be changed, other migration parameters can be changed under specific circumstances.

Migration_Pattern = SINGLE_ROUND_TRIPS

The following parameters can be changed as long as Migration_Pattern was serialized as SINGLE_ROUND_TRIPS. Changing this parameter will not impact those people who have determined their return trip before the file was serialized. After de-serializing, new decisions to return will use these parameters.

  • Air_Migration_Roundtrip_Probability

  • Family_Migration_Roundtrip_Probability

  • Local_Migration_Roundtrip_Probability

  • Regional_Migration_Roundtrip_Probability

  • Sea_Migration_Roundtrip_Probability

  • Air_Migration_Roundtrip_Duration

  • Family_Migration_Roundtrip_Duration

  • Local_Migration_Roundtrip_Duration

  • Regional_Migration_Roundtrip_Duration

  • Sea_Migration_Roundtrip_Duration

Enable_X_Migration

This includes the parameters Enable_Local_Migration, Enable_Region_Migration, Enable_Air_Migration, Enable_Sea_Migration, and Enable_Family_Migration.

  • ON-to-OFF: If Migration_Model = FIXED_RATE_MIGRATION and you turn these off, existing plans for migration - both out and return - will still occur. However, no new migration plans will be made.

  • OFF-to-ON: People should start migrating as designed.

Roundtrip_Waypoints

This can be changed under certain circumstances. If you serialized with Migration_Pattern set to WAYPOINTS_HOME, you can change this but it will NOT change the number of waypoints for the people that were serialized. All the people being born after de-serializing will receive the new number of waypoints.

Vector migration

Vector migration can be changed when reading from a serialized file. Vectors migrate differently then humans: each timestep a vector considers migrating; if they decide to migrate, they then go to the new node. They do not save state. Hence, if you turn it on or off, vectors will act like the new situation was always this way. NOTE however that Only female adult vectors migrate.

The following parameters can be changed:

  • Enable_Vector_Migration

  • Enable_Vector_Migration_Local

  • Enable_Vector_Migration_Regional

  • Vector_Migration_Filename_Local

  • Vector_Migration_Filename_Regional

  • Vector_Migration_Modifier_Equation

  • Vector_Migration_Food_Modifier

  • Vector_Migration_Habitat_Modifier

  • Vector_Migration_Stay_Put_Modifier

  • x_Vector_Migration_Local

  • x_Vector_Migration_Regional