A landmark factory specification is either a newly created instance or a landmark factory that has been defined previously. This page describes how one can specify a new landmark factory instance. For re-using landmark factories, see Landmark Predefinitions.

This plugin type can be predefined using --landmarks.

Exhaustive Landmarks

Exhaustively checks for each fact if it is a landmark.This check is done using relaxed planning.

lm_exhaust(verbosity=normal, only_causal_landmarks=false)

Language features supported:

h^m Landmarks

The landmark generation method introduced by Keyder, Richter & Helmert (ECAI 2010).

lm_hm(m=2, conjunctive_landmarks=true, verbosity=normal, use_orders=true)

Merged Landmarks

Merges the landmarks and orderings from the parameter landmarks

lm_merged(lm_factories, verbosity=normal)

Precedence: Fact landmarks take precedence over disjunctive landmarks, orderings take precedence in the usual manner (gn > nat > reas > o_reas).

Note: Does not currently support conjunctive landmarks

Language features supported:

HPS Orders

Adds reasonable orders and obedient reasonable orders described in the following paper

lm_reasonable_orders_hps(lm_factory, verbosity=normal)

Language features supported:

RHW Landmarks

The landmark generation method introduced by Richter, Helmert and Westphal (AAAI 2008).

lm_rhw(disjunctive_landmarks=true, verbosity=normal, use_orders=true, only_causal_landmarks=false)

Language features supported:

Zhu/Givan Landmarks

The landmark generation method introduced by Zhu & Givan (ICAPS 2003 Doctoral Consortium).

lm_zg(verbosity=normal, use_orders=true)

Language features supported:

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