Count globals rebased #245
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| @@ -582,3 +585,65 @@ def deepcopy(self, memodict={}): | |||
| return Cumulative(*copied_args) | |||
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| class GlobalCardinalityCount(GlobalConstraint): | |||
| """ | |||
| GlobalCardinalityCount(a,gcc): Collect the number of occurrences of each value 0..a.ub in gcc. | |||
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Can a contain arbitrary expressions, not only pure values? I guess yes, right?
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I do not yet see why we have this upper bound invariant (len(gcc) == ub + 1). Whether gcc is large or small compared to a does not really matter, len(gcc) just tells us something about the number of simple cardinality constraints implied by this global one. E.g., a=[1,2,5,4], gcc=[0,1,1] would simply be equivalent to Count(a,0)=0 & Count(a,1)=1 & Count(a,2)=1. And a=[1,2,5,4], gcc=[0,1,1,0,1,1] would simply be Count(a,0)=0 & Count(a,1)=1 & Count(a,2)=1 & Count(a,3)=0 & Count(a,4)=1 & Count(a,5)=1. What would be the problem here?
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with the bounds calculations pr that would be possible, as is only values or intvars are allowed
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with the bounds calculations pr that would be possible, as is only values or intvars are allowed
Can you elaborate what you mean?
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@Wout4 Review finished, let me know what you think! |
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I added a change to the bounds_calucation pr to calculate a.ub appropriatly for gcc |
| def value(self): | ||
| a, gcc = self.args | ||
| gval = [argval(y) for y in gcc] | ||
| return all([gval[i] == Count(a,i).value() for i in range(len(gcc))]) |
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I guess you could do all(self.decompose()).value()? Would be cleaner? or not possible?
| Count(arr,val) can only be decomposed if it's part of a comparison | ||
| """ | ||
| arr, val = self.args | ||
| return [eval_comparison(cmp_op, Operator('sum',[ai==val for ai in arr]), cmp_rhs)] |
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bit clumsy formulation.
why not using 'sum' as in value?
smth like cnt = sum(ai == val for ai in arr); eval_comparison(cmp_op, cnt, cmp_rhs)?
could be more readable...
| @@ -582,3 +585,65 @@ def deepcopy(self, memodict={}): | |||
| return Cumulative(*copied_args) | |||
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| class GlobalCardinalityCount(GlobalConstraint): | |||
| """ | |||
| GlobalCardinalityCount(a,gcc): Collect the number of occurrences of each value 0..a.ub in gcc. | |||
There was a problem hiding this comment.
I do not yet see why we have this upper bound invariant (len(gcc) == ub + 1). Whether gcc is large or small compared to a does not really matter, len(gcc) just tells us something about the number of simple cardinality constraints implied by this global one. E.g., a=[1,2,5,4], gcc=[0,1,1] would simply be equivalent to Count(a,0)=0 & Count(a,1)=1 & Count(a,2)=1. And a=[1,2,5,4], gcc=[0,1,1,0,1,1] would simply be Count(a,0)=0 & Count(a,1)=1 & Count(a,2)=1 & Count(a,3)=0 & Count(a,4)=1 & Count(a,5)=1. What would be the problem here?
| def value(self): | ||
| a, gcc = self.args | ||
| gval = [argval(y) for y in gcc] | ||
| return all([gval[i] == Count(a,i).value() for i in range(len(gcc))]) |
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Simpler, based on line 601: return all([Count(a, i).value() == argval(v) for i, v in enumerate(gcc)])
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| def deepcopy(self, memodict={}): | ||
| """ | ||
| Return a deep copy of the AllDifferentExceptO global constraint |
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GlobalCardinalityCount instead of AllDifferentExcept0
tests/test_globalconstraints.py
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| bv = cp.boolvar(5) | ||
| self.assertTrue(cp.Model(cp.Xor(bv)).solve()) | ||
| self.assertTrue(cp.Xor(bv).value()) | ||
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Do these tests belong here? I'm happy to let them piggy-back, but maybe something went wrong when splitting features / rebasing the branch.
| @@ -582,3 +585,65 @@ def deepcopy(self, memodict={}): | |||
| return Cumulative(*copied_args) | |||
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| class GlobalCardinalityCount(GlobalConstraint): | |||
| """ | |||
| GlobalCardinalityCount(a,gcc): Collect the number of occurrences of each value 0..a.ub in gcc. | |||
There was a problem hiding this comment.
with the bounds calculations pr that would be possible, as is only values or intvars are allowed
Can you elaborate what you mean?
No description provided.