Add step option to FlatZinc driver

git-svn-id: file:///Users/tack/GecodeGitMigration/gecode-svn-mirror/gecode/trunk@14463 e85b7adc-8362-4630-8c63-7469d557c915

Author: guidotack

changelog.in

@@ -72,6 +72,14 @@ Date: 2015-03-20
 [DESCRIPTION]
 Yada! Yada!
 
+[ENTRY]
+Module: flatzinc
+What:   new
+Rank:   minor
+[DESCRIPTION]
+An option -step now can pass an improvement step for
+optimization of float problems.
+
 [ENTRY]
 Module: driver
 What:   change

gecode/flatzinc.hh

@@ -223,6 +223,7 @@ namespace Gecode { namespace FlatZinc {
       Gecode::Driver::BoolOption        _nogoods;   ///< Whether to use no-goods
       Gecode::Driver::UnsignedIntOption _nogoods_limit; ///< Depth limit for extracting no-goods
       Gecode::Driver::BoolOption        _interrupt; ///< Whether to catch SIGINT
+      Gecode::Driver::DoubleOption      _step;        ///< Step option
       //@}
 
       /// \name Execution options
@@ -255,6 +256,7 @@ namespace Gecode { namespace FlatZinc {
                      Search::Config::nogoods_limit),
       _interrupt("-interrupt","whether to catch Ctrl-C (true) or not (false)",
                  true),
+      _step("-step","step distance for float optimization",0.0),
       _mode("-mode","how to execute script",Gecode::SM_SOLUTION),
       _stat("-s","emit statistics"),
       _output("-o","file to send output to") {
@@ -274,6 +276,7 @@ namespace Gecode { namespace FlatZinc {
       add(_decay);
       add(_node); add(_fail); add(_time); add(_interrupt);
       add(_seed);
+      add(_step);
       add(_restart); add(_r_base); add(_r_scale); 
       add(_nogoods); add(_nogoods_limit);
       add(_mode); add(_stat);
@@ -306,6 +309,7 @@ namespace Gecode { namespace FlatZinc {
     unsigned int fail(void) const { return _fail.value(); }
     unsigned int time(void) const { return _time.value(); }
     int seed(void) const { return _seed.value(); }
+    double step(void) const { return _step.value(); }
     const char* output(void) const { return _output.value(); }
     Gecode::ScriptMode mode(void) const {
       return static_cast<Gecode::ScriptMode>(_mode.value());
@@ -452,6 +456,8 @@ namespace Gecode { namespace FlatZinc {
     Gecode::FloatVarArray fv_aux;
     /// Indicates whether a float variable is introduced by mzn2fzn
     std::vector<bool> fv_introduced;
+    /// Step by which a next solution has to have lower cost
+    Gecode::FloatNum step;
 #endif
     /// Whether the introduced variables still need to be copied
     bool needAuxVars;

gecode/flatzinc/flatzinc.cpp

@@ -623,6 +623,9 @@ namespace Gecode { namespace FlatZinc {
   FlatZincSpace::FlatZincSpace(bool share, FlatZincSpace& f)
     : Space(share, f), _random(f._random),
       _solveAnnotations(NULL), iv_boolalias(NULL),
+#ifdef GECODE_HAS_FLOAT_VARS
+      step(f.step),
+#endif
       needAuxVars(f.needAuxVars) {
       _optVar = f._optVar;
       _optVarIsInt = f._optVarIsInt;
@@ -1475,6 +1478,9 @@ namespace Gecode { namespace FlatZinc {
                                           true);
     o.c_d = opt.c_d();
     o.a_d = opt.a_d();
+#ifdef GECODE_HAS_FLOAT_VARS    
+    step = opt.step();
+#endif
     o.threads = opt.threads();
     o.nogoods_limit = opt.nogoods() ? opt.nogoods_limit() : 0;
     o.cutoff  = Driver::createCutoff(opt);
@@ -1603,10 +1609,10 @@ namespace Gecode { namespace FlatZinc {
 #ifdef GECODE_HAS_FLOAT_VARS
       if (_method == MIN)
         rel(*this, fv[_optVar], FRT_LE, 
-                   static_cast<const FlatZincSpace*>(&s)->fv[_optVar].val());
+                   static_cast<const FlatZincSpace*>(&s)->fv[_optVar].val()-step);
       else if (_method == MAX)
         rel(*this, fv[_optVar], FRT_GR,
-                   static_cast<const FlatZincSpace*>(&s)->fv[_optVar].val());
+                   static_cast<const FlatZincSpace*>(&s)->fv[_optVar].val()+step);
 #endif
     }
   }