如何使用 Add Multiplication Equality 添加约束？
How to use AddMultiplicationEquality to add constrain?
例如，我有下面的数字列表。并且限制是相邻两个数的差距应该是正数或负数，或者两个数之一等于零，也就是说一正一负（例如3和-1）是不可接受的。
List numbers: [15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 18, 17, 20, 19,
22, 25, 25, 25, 25, 25, 25, 25, 25, 22, 20, 23, 22, 21, 18, 15, 15,
15, 15, 15, 15, 15, 18, 21, 24, 24, 24, 27, 30]
Numbers' gap: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, -1, 3, -1, 3, 3, 0, 0, 0, 0,
0, 0, 0, -3, -2, 3, -1, -1, -3, -3, 0, 0, 0, 0, 0, 0, 3, 3, 3, 0, 0,
3, 3]
所以我尝试使用AddMultiplicationEquality来添加约束
target=model.NewIntVar(-999999,999999,'target_%s_%s'%(i, i+1))
model.AddMultiplicationEquality(target, [gap[i],gap[i+1]])
model.Add(target>=0)
但是我得到了下面的结果。我该如何解决这个问题？提前致谢。
Not supported
*** Check failure stack trace: ***
@ 0x10956c8ed google::LogMessage::Fail()
@ 0x10956b29e google::LogMessage::SendToLog()
@ 0x10956bebf google::LogMessage::Flush()
@ 0x109570c19 google::LogMessageFatal::~LogMessageFatal()
@ 0x10956cf55 google::LogMessageFatal::~LogMessageFatal()
@ 0x10a7948e4 _ZZN19operations_research3sat17ProductConstraintEN3gtl7IntTypeINS0_20IntegerVariable_tag_EiEES4_S4_ENKUlPNS0_5ModelEE_clES6_
@ 0x10a787dfc operations_research::sat::LoadIntProdConstraint()
@ 0x10a7916da operations_research::sat::LoadConstraint()
@ 0x10a7c36e1 operations_research::sat::CpModelPresolver::Probe()
@ 0x10a7ceba8 operations_research::sat::CpModelPresolver::Presolve()
@ 0x10a7ce756 operations_research::sat::PresolveCpModel()
@ 0x10a7e3f7a operations_research::sat::SolveCpModel()
如评论中所见，7.7 后已修复此问题
现在，如果不使用乘法的结果，使用AddMultiplicationEquality是低效的。
对于每个间隙编号，我会创建两个布尔变量。
is_gt_zero[i] = model.NewBoolVar('')
model.Add(gap[i] > 0).OnlyEnforceIf(is_gt_zero[i])
model.Add(gap[i] <= 0).OnlyEnforceIf(is_gt_zero[i].Not())
is_lt_zero[i] = model.NewBoolVar('')
model.Add(gap[i] < 0).OnlyEnforceIf(is_lt_zero[i])
model.Add(gap[i] >= 0).OnlyEnforceIf(is_lt_zero[i].Not())
然后强制兼容性。
model.AddImplication(is_gt_zero[i], is_lt_zero[i + 1].Not())
model.AddImplication(is_lt_zero[i], is_gt_zero[i + 1].Not())
例如，我有下面的数字列表。并且限制是相邻两个数的差距应该是正数或负数，或者两个数之一等于零，也就是说一正一负（例如3和-1）是不可接受的。
List numbers: [15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 18, 17, 20, 19, 22, 25, 25, 25, 25, 25, 25, 25, 25, 22, 20, 23, 22, 21, 18, 15, 15, 15, 15, 15, 15, 15, 18, 21, 24, 24, 24, 27, 30]
Numbers' gap: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, -1, 3, -1, 3, 3, 0, 0, 0, 0, 0, 0, 0, -3, -2, 3, -1, -1, -3, -3, 0, 0, 0, 0, 0, 0, 3, 3, 3, 0, 0, 3, 3]
所以我尝试使用AddMultiplicationEquality来添加约束
target=model.NewIntVar(-999999,999999,'target_%s_%s'%(i, i+1))
model.AddMultiplicationEquality(target, [gap[i],gap[i+1]])
model.Add(target>=0)
但是我得到了下面的结果。我该如何解决这个问题？提前致谢。
Not supported
*** Check failure stack trace: ***
@ 0x10956c8ed google::LogMessage::Fail()
@ 0x10956b29e google::LogMessage::SendToLog()
@ 0x10956bebf google::LogMessage::Flush()
@ 0x109570c19 google::LogMessageFatal::~LogMessageFatal()
@ 0x10956cf55 google::LogMessageFatal::~LogMessageFatal()
@ 0x10a7948e4 _ZZN19operations_research3sat17ProductConstraintEN3gtl7IntTypeINS0_20IntegerVariable_tag_EiEES4_S4_ENKUlPNS0_5ModelEE_clES6_
@ 0x10a787dfc operations_research::sat::LoadIntProdConstraint()
@ 0x10a7916da operations_research::sat::LoadConstraint()
@ 0x10a7c36e1 operations_research::sat::CpModelPresolver::Probe()
@ 0x10a7ceba8 operations_research::sat::CpModelPresolver::Presolve()
@ 0x10a7ce756 operations_research::sat::PresolveCpModel()
@ 0x10a7e3f7a operations_research::sat::SolveCpModel()
如评论中所见，7.7 后已修复此问题
现在，如果不使用乘法的结果，使用AddMultiplicationEquality是低效的。
对于每个间隙编号，我会创建两个布尔变量。
is_gt_zero[i] = model.NewBoolVar('')
model.Add(gap[i] > 0).OnlyEnforceIf(is_gt_zero[i])
model.Add(gap[i] <= 0).OnlyEnforceIf(is_gt_zero[i].Not())
is_lt_zero[i] = model.NewBoolVar('')
model.Add(gap[i] < 0).OnlyEnforceIf(is_lt_zero[i])
model.Add(gap[i] >= 0).OnlyEnforceIf(is_lt_zero[i].Not())
然后强制兼容性。
model.AddImplication(is_gt_zero[i], is_lt_zero[i + 1].Not())
model.AddImplication(is_lt_zero[i], is_gt_zero[i + 1].Not())