[python] merge pytoulbar2 from master and add vaclin option

pytoulbar2/pytoulbar2.py

@@ -20,6 +20,7 @@ class CFN:
         ubinit (decimal cost or None): initial upper bound.
         resolution (int): decimal precision of costs.
         vac (int): if non zero, maximum solver depth minus one where virtual arc consistency algorithm is applied (1: VAC only in preprocessing).
+        vaclin (bool): if true and vac is non-zero then virtual arc consistency algorithm is also applied on (generalized) linear constraints
         configuration (bool): if True then special settings for preference learning using incremental solving (see car configuration tutorial).
         vns (int or None): if None then solves using branch-and-bound methods else using variable neighborhood search heuristic
                            (-1: initial solution at random, -2: minimum domain values, -3: maximum domain values, 
@@ -47,11 +48,12 @@ class CFN:
     See pytoulbar2test.py example in src repository.
     
     """
-    def __init__(self, ubinit = None, resolution = 0, vac = 0, configuration = False, vns = None, seed = 1, verbose = -1):
+    def __init__(self, ubinit = None, resolution = 0, vac = 0, configuration = False, vns = None, seed = 1, verbose = -1, vaclin = True):
         tb2.init()
         
         tb2.option.decimalPoint = resolution   # decimal precision of costs
         tb2.option.vac = vac   # if no zero, maximum search depth-1 where VAC algorithm is performed (use 1 for preprocessing only)
+        tb2.option.VAClin = vaclin # if true then VAC is also applied on linear constraints
         tb2.option.seed = seed    # random seed number (use -1 if a pseudo-randomly generated seed is wanted)
         tb2.option.verbose = verbose   # verbosity level of toulbar2 (-1:no message, 0:search statistics, 1:search tree, 2-7: propagation information)
 
@@ -163,10 +165,16 @@ class CFN:
                 raise RuntimeError("Out of range variable index:"+str(v))
             iscope.append(v) 
             
-        if (len(iscope) == 0):
-            assert(isinstance(costs, (int, float)))
+        if (len(iscope) == 0 and isinstance(costs, (int, float))):
             self.CFN.wcsp.postNullaryConstraint(costs)
-        elif (len(iscope) == 1):
+            return
+        mincost = min(costs)
+        maxcost = max(costs)
+        if (mincost == maxcost):
+            self.CFN.wcsp.postNullaryConstraint(mincost)
+            return
+        assert(len(iscope) >= 1)
+        if (len(iscope) == 1):
             assert(self.CFN.wcsp.getDomainInitSize(iscope[0]) == len(costs))
             self.CFN.wcsp.postUnaryConstraint(iscope[0], costs, incremental)
         elif (len(iscope) == 2):
@@ -178,11 +186,7 @@ class CFN:
         else:
             if incremental:
                 raise NameError('Sorry, incremental ' + str(len(iscope)) + '-arity cost functions not implemented yet in toulbar2.')
-            mincost = min(costs)
-            maxcost = max(costs)
             self.CFN.wcsp.postNullaryConstraint(mincost)
-            if (mincost == maxcost):
-                return
             idx = self.CFN.wcsp.postNaryConstraintBegin(iscope, 0, len(costs) - costs.count(0))
             tuple = [self.CFN.wcsp.toValue(v, 0) for v in iscope]
             for cost in costs:
@@ -231,7 +235,14 @@ class CFN:
         if (len(iscope) == 0):
             assert(len(tuples) == 0)
             self.CFN.wcsp.postNullaryConstraint(defcost)
-        elif (len(iscope) == 1):
+            return
+        mincost = min(defcost, min(tcosts))
+        maxcost = max(defcost, max(tcosts))
+        if (mincost == maxcost):
+            self.CFN.wcsp.postNullaryConstraint(mincost)
+            return
+        assert(len(iscope) >= 1)
+        if (len(iscope) == 1):
             costs = [defcost] * self.CFN.wcsp.getDomainInitSize(iscope[0])
             for i, tuple in enumerate(tuples):
                 costs[self.CFN.wcsp.toIndex(iscope[0], tuple[0])] = tcosts[i]
@@ -249,11 +260,8 @@ class CFN:
         else:
             if incremental:
                 raise NameError('Sorry, incremental ' + str(len(iscope)) + '-arity cost functions not implemented yet in toulbar2.')
-            mincost = min(defcost, min(tcosts))
-            maxcost = max(defcost, max(tcosts))
+            
             self.CFN.wcsp.postNullaryConstraint(mincost)
-            if (mincost == maxcost):
-                return
             idx = self.CFN.wcsp.postNaryConstraintBegin(iscope, int((defcost - mincost) * 10 ** tb2.option.decimalPoint), len(tcosts))
             for i, tuple in enumerate(tuples):
                 self.CFN.wcsp.postNaryConstraintTuple(idx, [self.CFN.wcsp.toValue(iscope[x], self.CFN.wcsp.toIndex(iscope[x], v)) for x,v in enumerate(tuple)], int((tcosts[i] - mincost) * 10 ** tb2.option.decimalPoint))

src/pytoulbar2.cpp

@@ -165,6 +165,7 @@ PYBIND11_MODULE(pytb2, m)
         .def_readwrite_static("opb", &ToulBar2::opb)
         .def_readwrite_static("addAMOConstraints", &ToulBar2::addAMOConstraints)
         .def_readwrite_static("knapsackDP", &ToulBar2::knapsackDP)
+        .def_readwrite_static("VAClin", &ToulBar2::VAClin)
         .def_readwrite_static("divNbSol", &ToulBar2::divNbSol)
         .def_readwrite_static("divBound", &ToulBar2::divBound)
         .def_readwrite_static("divWidth", &ToulBar2::divWidth)