Merge pull request Pyomo#3227 from emma58/sequence-var

contrib.cp: Adding SequenceVar and other logical expressions for scheduling

pyomo/contrib/cp/__init__.py

@@ -17,6 +17,19 @@
     IntervalVarPresence,
 )
 from pyomo.contrib.cp.repn.docplex_writer import DocplexWriter, CPOptimizerSolver
+from pyomo.contrib.cp.sequence_var import SequenceVar
+from pyomo.contrib.cp.scheduling_expr.sequence_expressions import (
+    no_overlap,
+    first_in_sequence,
+    last_in_sequence,
+    before_in_sequence,
+    predecessor_to,
+)
+from pyomo.contrib.cp.scheduling_expr.scheduling_logic import (
+    alternative,
+    spans,
+    synchronize,
+)
 from pyomo.contrib.cp.scheduling_expr.step_function_expressions import (
     AlwaysIn,
     Step,

pyomo/contrib/cp/interval_var.py

@@ -11,6 +11,7 @@
 
 from pyomo.common.collections import ComponentSet
 from pyomo.common.pyomo_typing import overload
+from pyomo.contrib.cp.scheduling_expr.scheduling_logic import SpanExpression
 from pyomo.contrib.cp.scheduling_expr.precedence_expressions import (
     BeforeExpression,
     AtExpression,
@@ -24,6 +25,7 @@
 from pyomo.core.base.indexed_component import IndexedComponent, UnindexedComponent_set
 from pyomo.core.base.initializer import BoundInitializer, Initializer
 from pyomo.core.expr import GetItemExpression
+from pyomo.core.expr.logical_expr import _flattened
 
 
 class IntervalVarTimePoint(ScalarVar):
@@ -49,15 +51,15 @@ class IntervalVarStartTime(IntervalVarTimePoint):
     """This class defines a single variable denoting a start time point
     of an IntervalVar"""
 
-    def __init__(self):
+    def __init__(self, *args, **kwd):
         super().__init__(domain=Integers, ctype=IntervalVarStartTime)
 
 
 class IntervalVarEndTime(IntervalVarTimePoint):
     """This class defines a single variable denoting an end time point
     of an IntervalVar"""
 
-    def __init__(self):
+    def __init__(self, *args, **kwd):
         super().__init__(domain=Integers, ctype=IntervalVarEndTime)
 
 
@@ -67,7 +69,7 @@ class IntervalVarLength(ScalarVar):
 
     __slots__ = ()
 
-    def __init__(self):
+    def __init__(self, *args, **kwd):
         super().__init__(domain=Integers, ctype=IntervalVarLength)
 
     def get_associated_interval_var(self):
@@ -80,7 +82,9 @@ class IntervalVarPresence(ScalarBooleanVar):
 
     __slots__ = ()
 
-    def __init__(self):
+    def __init__(self, *args, **kwd):
+        # TODO: adding args and kwd above made Reference work, but we
+        # probably shouldn't just swallow them, right?
         super().__init__(ctype=IntervalVarPresence)
 
     def get_associated_interval_var(self):
@@ -122,6 +126,9 @@ def optional(self, val):
         else:
             self.is_present.fix(True)
 
+    def spans(self, *args):
+        return SpanExpression([self] + list(_flattened(args)))
+
 
 @ModelComponentFactory.register("Interval variables for scheduling.")
 class IntervalVar(Block):