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ModelRef Class Reference
Inheritance diagram for ModelRef:

Public Member Functions

 __init__ (self, m, ctx)
 __del__ (self)
 __repr__ (self)
 sexpr (self)
 eval (self, t, model_completion=False)
 evaluate (self, t, model_completion=False)
 __len__ (self)
 get_interp (self, decl)
 num_sorts (self)
 get_sort (self, idx)
 sorts (self)
 get_universe (self, s)
 __getitem__ (self, idx)
 decls (self)
 update_value (self, x, value)
 translate (self, target)
 project (self, vars, fml)
 project_with_witness (self, vars, fml)
 __copy__ (self)
 __deepcopy__ (self, memo={})
Public Member Functions inherited from Z3PPObject
 use_pp (self)

Data Fields

 model = m
 ctx = ctx

Additional Inherited Members

Protected Member Functions inherited from Z3PPObject
 _repr_html_ (self)

Detailed Description

Model/Solution of a satisfiability problem (aka system of constraints).

Definition at line 6581 of file z3py.py.

Constructor & Destructor Documentation

◆ __init__()

__init__ ( self,
m,
ctx )

Definition at line 6584 of file z3py.py.

6584 def __init__(self, m, ctx):
6585 assert ctx is not None
6586 self.model = m
6587 self.ctx = ctx
6588 Z3_model_inc_ref(self.ctx.ref(), self.model)
6589
void Z3_API Z3_model_inc_ref(Z3_context c, Z3_model m)
Increment the reference counter of the given model.

◆ __del__()

__del__ ( self)

Definition at line 6590 of file z3py.py.

6590 def __del__(self):
6591 if self.ctx.ref() is not None and Z3_model_dec_ref is not None:
6592 Z3_model_dec_ref(self.ctx.ref(), self.model)
6593
void Z3_API Z3_model_dec_ref(Z3_context c, Z3_model m)
Decrement the reference counter of the given model.

Member Function Documentation

◆ __copy__()

__copy__ ( self)

Definition at line 6920 of file z3py.py.

6920 def __copy__(self):
6921 return self.translate(self.ctx)
6922

◆ __deepcopy__()

__deepcopy__ ( self,
memo = {} )

Definition at line 6923 of file z3py.py.

6923 def __deepcopy__(self, memo={}):
6924 return self.translate(self.ctx)
6925
6926

◆ __getitem__()

__getitem__ ( self,
idx )
If `idx` is an integer, then the declaration at position `idx` in the model `self` is returned.
If `idx` is a declaration, then the actual interpretation is returned.

The elements can be retrieved using position or the actual declaration.

>>> f = Function('f', IntSort(), IntSort())
>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, x < 2, f(x) == 0)
>>> s.check()
sat
>>> m = s.model()
>>> len(m)
2
>>> m[0]
x
>>> m[1]
f
>>> m[x]
1
>>> m[f]
[else -> 0]
>>> for d in m: print("%s -> %s" % (d, m[d]))
x -> 1
f -> [else -> 0]

Definition at line 6802 of file z3py.py.

6802 def __getitem__(self, idx):
6803 """If `idx` is an integer, then the declaration at position `idx` in the model `self` is returned.
6804 If `idx` is a declaration, then the actual interpretation is returned.
6805
6806 The elements can be retrieved using position or the actual declaration.
6807
6808 >>> f = Function('f', IntSort(), IntSort())
6809 >>> x = Int('x')
6810 >>> s = Solver()
6811 >>> s.add(x > 0, x < 2, f(x) == 0)
6812 >>> s.check()
6813 sat
6814 >>> m = s.model()
6815 >>> len(m)
6816 2
6817 >>> m[0]
6818 x
6819 >>> m[1]
6820 f
6821 >>> m[x]
6822 1
6823 >>> m[f]
6824 [else -> 0]
6825 >>> for d in m: print("%s -> %s" % (d, m[d]))
6826 x -> 1
6827 f -> [else -> 0]
6828 """
6829 if _is_int(idx):
6830 if idx >= len(self):
6831 raise IndexError
6832 num_consts = Z3_model_get_num_consts(self.ctx.ref(), self.model)
6833 if (idx < num_consts):
6834 return FuncDeclRef(Z3_model_get_const_decl(self.ctx.ref(), self.model, idx), self.ctx)
6835 else:
6836 return FuncDeclRef(Z3_model_get_func_decl(self.ctx.ref(), self.model, idx - num_consts), self.ctx)
6837 if isinstance(idx, FuncDeclRef):
6838 return self.get_interp(idx)
6839 if is_const(idx):
6840 return self.get_interp(idx.decl())
6841 if isinstance(idx, SortRef):
6842 return self.get_universe(idx)
6843 if z3_debug():
6844 _z3_assert(False, "Integer, Z3 declaration, or Z3 constant expected")
6845 return None
6846
Z3_func_decl Z3_API Z3_model_get_func_decl(Z3_context c, Z3_model m, unsigned i)
Return the declaration of the i-th function in the given model.
unsigned Z3_API Z3_model_get_num_consts(Z3_context c, Z3_model m)
Return the number of constants assigned by the given model.
Z3_func_decl Z3_API Z3_model_get_const_decl(Z3_context c, Z3_model m, unsigned i)
Return the i-th constant in the given model.

◆ __len__()

__len__ ( self)
Return the number of constant and function declarations in the model `self`.

>>> f = Function('f', IntSort(), IntSort())
>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, f(x) != x)
>>> s.check()
sat
>>> m = s.model()
>>> len(m)
2

Definition at line 6658 of file z3py.py.

6658 def __len__(self):
6659 """Return the number of constant and function declarations in the model `self`.
6660
6661 >>> f = Function('f', IntSort(), IntSort())
6662 >>> x = Int('x')
6663 >>> s = Solver()
6664 >>> s.add(x > 0, f(x) != x)
6665 >>> s.check()
6666 sat
6667 >>> m = s.model()
6668 >>> len(m)
6669 2
6670 """
6671 num_consts = int(Z3_model_get_num_consts(self.ctx.ref(), self.model))
6672 num_funcs = int(Z3_model_get_num_funcs(self.ctx.ref(), self.model))
6673 return num_consts + num_funcs
6674
unsigned Z3_API Z3_model_get_num_funcs(Z3_context c, Z3_model m)
Return the number of function interpretations in the given model.

◆ __repr__()

__repr__ ( self)

Definition at line 6594 of file z3py.py.

6594 def __repr__(self):
6595 return obj_to_string(self)
6596

◆ decls()

decls ( self)
Return a list with all symbols that have an interpretation in the model `self`.
>>> f = Function('f', IntSort(), IntSort())
>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, x < 2, f(x) == 0)
>>> s.check()
sat
>>> m = s.model()
>>> m.decls()
[x, f]

Definition at line 6847 of file z3py.py.

6847 def decls(self):
6848 """Return a list with all symbols that have an interpretation in the model `self`.
6849 >>> f = Function('f', IntSort(), IntSort())
6850 >>> x = Int('x')
6851 >>> s = Solver()
6852 >>> s.add(x > 0, x < 2, f(x) == 0)
6853 >>> s.check()
6854 sat
6855 >>> m = s.model()
6856 >>> m.decls()
6857 [x, f]
6858 """
6859 r = []
6860 for i in range(Z3_model_get_num_consts(self.ctx.ref(), self.model)):
6861 r.append(FuncDeclRef(Z3_model_get_const_decl(self.ctx.ref(), self.model, i), self.ctx))
6862 for i in range(Z3_model_get_num_funcs(self.ctx.ref(), self.model)):
6863 r.append(FuncDeclRef(Z3_model_get_func_decl(self.ctx.ref(), self.model, i), self.ctx))
6864 return r
6865

◆ eval()

eval ( self,
t,
model_completion = False )
Evaluate the expression `t` in the model `self`.
If `model_completion` is enabled, then a default interpretation is automatically added
for symbols that do not have an interpretation in the model `self`.

>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, x < 2)
>>> s.check()
sat
>>> m = s.model()
>>> m.eval(x + 1)
2
>>> m.eval(x == 1)
True
>>> y = Int('y')
>>> m.eval(y + x)
1 + y
>>> m.eval(y)
y
>>> m.eval(y, model_completion=True)
0
>>> # Now, m contains an interpretation for y
>>> m.eval(y + x)
1

Definition at line 6601 of file z3py.py.

6601 def eval(self, t, model_completion=False):
6602 """Evaluate the expression `t` in the model `self`.
6603 If `model_completion` is enabled, then a default interpretation is automatically added
6604 for symbols that do not have an interpretation in the model `self`.
6605
6606 >>> x = Int('x')
6607 >>> s = Solver()
6608 >>> s.add(x > 0, x < 2)
6609 >>> s.check()
6610 sat
6611 >>> m = s.model()
6612 >>> m.eval(x + 1)
6613 2
6614 >>> m.eval(x == 1)
6615 True
6616 >>> y = Int('y')
6617 >>> m.eval(y + x)
6618 1 + y
6619 >>> m.eval(y)
6620 y
6621 >>> m.eval(y, model_completion=True)
6622 0
6623 >>> # Now, m contains an interpretation for y
6624 >>> m.eval(y + x)
6625 1
6626 """
6627 r = (Ast * 1)()
6628 if Z3_model_eval(self.ctx.ref(), self.model, t.as_ast(), model_completion, r):
6629 return _to_expr_ref(r[0], self.ctx)
6630 raise Z3Exception("failed to evaluate expression in the model")
6631
bool Z3_API Z3_model_eval(Z3_context c, Z3_model m, Z3_ast t, bool model_completion, Z3_ast *v)
Evaluate the AST node t in the given model. Return true if succeeded, and store the result in v.

Referenced by evaluate().

◆ evaluate()

evaluate ( self,
t,
model_completion = False )
Alias for `eval`.

>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, x < 2)
>>> s.check()
sat
>>> m = s.model()
>>> m.evaluate(x + 1)
2
>>> m.evaluate(x == 1)
True
>>> y = Int('y')
>>> m.evaluate(y + x)
1 + y
>>> m.evaluate(y)
y
>>> m.evaluate(y, model_completion=True)
0
>>> # Now, m contains an interpretation for y
>>> m.evaluate(y + x)
1

Definition at line 6632 of file z3py.py.

6632 def evaluate(self, t, model_completion=False):
6633 """Alias for `eval`.
6634
6635 >>> x = Int('x')
6636 >>> s = Solver()
6637 >>> s.add(x > 0, x < 2)
6638 >>> s.check()
6639 sat
6640 >>> m = s.model()
6641 >>> m.evaluate(x + 1)
6642 2
6643 >>> m.evaluate(x == 1)
6644 True
6645 >>> y = Int('y')
6646 >>> m.evaluate(y + x)
6647 1 + y
6648 >>> m.evaluate(y)
6649 y
6650 >>> m.evaluate(y, model_completion=True)
6651 0
6652 >>> # Now, m contains an interpretation for y
6653 >>> m.evaluate(y + x)
6654 1
6655 """
6656 return self.eval(t, model_completion)
6657

◆ get_interp()

get_interp ( self,
decl )
Return the interpretation for a given declaration or constant.

>>> f = Function('f', IntSort(), IntSort())
>>> x = Int('x')
>>> s = Solver()
>>> s.add(x > 0, x < 2, f(x) == 0)
>>> s.check()
sat
>>> m = s.model()
>>> m[x]
1
>>> m[f]
[else -> 0]

Definition at line 6675 of file z3py.py.

6675 def get_interp(self, decl):
6676 """Return the interpretation for a given declaration or constant.
6677
6678 >>> f = Function('f', IntSort(), IntSort())
6679 >>> x = Int('x')
6680 >>> s = Solver()
6681 >>> s.add(x > 0, x < 2, f(x) == 0)
6682 >>> s.check()
6683 sat
6684 >>> m = s.model()
6685 >>> m[x]
6686 1
6687 >>> m[f]
6688 [else -> 0]
6689 """
6690 if z3_debug():
6691 _z3_assert(isinstance(decl, FuncDeclRef) or is_const(decl), "Z3 declaration expected")
6692 if is_const(decl):
6693 decl = decl.decl()
6694 try:
6695 if decl.arity() == 0:
6696 _r = Z3_model_get_const_interp(self.ctx.ref(), self.model, decl.ast)
6697 if _r.value is None:
6698 return None
6699 r = _to_expr_ref(_r, self.ctx)
6700 if is_as_array(r):
6701 fi = self.get_interp(get_as_array_func(r))
6702 if fi is None:
6703 return fi
6704 e = fi.else_value()
6705 if e is None:
6706 return fi
6707 if fi.arity() != 1:
6708 return fi
6709 srt = decl.range()
6710 dom = srt.domain()
6711 e = K(dom, e)
6712 i = 0
6713 sz = fi.num_entries()
6714 n = fi.arity()
6715 while i < sz:
6716 fe = fi.entry(i)
6717 e = Store(e, fe.arg_value(0), fe.value())
6718 i += 1
6719 return e
6720 else:
6721 return r
6722 else:
6723 return FuncInterp(Z3_model_get_func_interp(self.ctx.ref(), self.model, decl.ast), self.ctx)
6724 except Z3Exception:
6725 return None
6726
Z3_ast Z3_API Z3_model_get_const_interp(Z3_context c, Z3_model m, Z3_func_decl a)
Return the interpretation (i.e., assignment) of constant a in the model m. Return NULL,...
Z3_func_interp Z3_API Z3_model_get_func_interp(Z3_context c, Z3_model m, Z3_func_decl f)
Return the interpretation of the function f in the model m. Return NULL, if the model does not assign...

Referenced by __getitem__(), and get_interp().

◆ get_sort()

get_sort ( self,
idx )
Return the uninterpreted sort at position `idx` < self.num_sorts().

>>> A = DeclareSort('A')
>>> B = DeclareSort('B')
>>> a1, a2 = Consts('a1 a2', A)
>>> b1, b2 = Consts('b1 b2', B)
>>> s = Solver()
>>> s.add(a1 != a2, b1 != b2)
>>> s.check()
sat
>>> m = s.model()
>>> m.num_sorts()
2
>>> m.get_sort(0)
A
>>> m.get_sort(1)
B

Definition at line 6742 of file z3py.py.

6742 def get_sort(self, idx):
6743 """Return the uninterpreted sort at position `idx` < self.num_sorts().
6744
6745 >>> A = DeclareSort('A')
6746 >>> B = DeclareSort('B')
6747 >>> a1, a2 = Consts('a1 a2', A)
6748 >>> b1, b2 = Consts('b1 b2', B)
6749 >>> s = Solver()
6750 >>> s.add(a1 != a2, b1 != b2)
6751 >>> s.check()
6752 sat
6753 >>> m = s.model()
6754 >>> m.num_sorts()
6755 2
6756 >>> m.get_sort(0)
6757 A
6758 >>> m.get_sort(1)
6759 B
6760 """
6761 if idx >= self.num_sorts():
6762 raise IndexError
6763 return _to_sort_ref(Z3_model_get_sort(self.ctx.ref(), self.model, idx), self.ctx)
6764
Z3_sort Z3_API Z3_model_get_sort(Z3_context c, Z3_model m, unsigned i)
Return a uninterpreted sort that m assigns an interpretation.

Referenced by sorts().

◆ get_universe()

get_universe ( self,
s )
Return the interpretation for the uninterpreted sort `s` in the model `self`.

>>> A = DeclareSort('A')
>>> a, b = Consts('a b', A)
>>> s = Solver()
>>> s.add(a != b)
>>> s.check()
sat
>>> m = s.model()
>>> m.get_universe(A)
[A!val!1, A!val!0]

Definition at line 6782 of file z3py.py.

6782 def get_universe(self, s):
6783 """Return the interpretation for the uninterpreted sort `s` in the model `self`.
6784
6785 >>> A = DeclareSort('A')
6786 >>> a, b = Consts('a b', A)
6787 >>> s = Solver()
6788 >>> s.add(a != b)
6789 >>> s.check()
6790 sat
6791 >>> m = s.model()
6792 >>> m.get_universe(A)
6793 [A!val!1, A!val!0]
6794 """
6795 if z3_debug():
6796 _z3_assert(isinstance(s, SortRef), "Z3 sort expected")
6797 try:
6798 return AstVector(Z3_model_get_sort_universe(self.ctx.ref(), self.model, s.ast), self.ctx)
6799 except Z3Exception:
6800 return None
6801
Z3_ast_vector Z3_API Z3_model_get_sort_universe(Z3_context c, Z3_model m, Z3_sort s)
Return the finite set of distinct values that represent the interpretation for sort s.

Referenced by __getitem__().

◆ num_sorts()

num_sorts ( self)
Return the number of uninterpreted sorts that contain an interpretation in the model `self`.

>>> A = DeclareSort('A')
>>> a, b = Consts('a b', A)
>>> s = Solver()
>>> s.add(a != b)
>>> s.check()
sat
>>> m = s.model()
>>> m.num_sorts()
1

Definition at line 6727 of file z3py.py.

6727 def num_sorts(self):
6728 """Return the number of uninterpreted sorts that contain an interpretation in the model `self`.
6729
6730 >>> A = DeclareSort('A')
6731 >>> a, b = Consts('a b', A)
6732 >>> s = Solver()
6733 >>> s.add(a != b)
6734 >>> s.check()
6735 sat
6736 >>> m = s.model()
6737 >>> m.num_sorts()
6738 1
6739 """
6740 return int(Z3_model_get_num_sorts(self.ctx.ref(), self.model))
6741
unsigned Z3_API Z3_model_get_num_sorts(Z3_context c, Z3_model m)
Return the number of uninterpreted sorts that m assigns an interpretation to.

Referenced by get_sort(), and sorts().

◆ project()

project ( self,
vars,
fml )
Perform model-based projection on fml with respect to vars.
Assume that the model satisfies fml. Then compute a projection fml_p, such
that vars do not occur free in fml_p, fml_p is true in the model and
fml_p => exists vars . fml

Definition at line 6896 of file z3py.py.

6896 def project(self, vars, fml):
6897 """Perform model-based projection on fml with respect to vars.
6898 Assume that the model satisfies fml. Then compute a projection fml_p, such
6899 that vars do not occur free in fml_p, fml_p is true in the model and
6900 fml_p => exists vars . fml
6901 """
6902 ctx = self.ctx.ref()
6903 _vars = (Ast * len(vars))()
6904 for i in range(len(vars)):
6905 _vars[i] = vars[i].as_ast()
6906 return _to_expr_ref(Z3_qe_model_project(ctx, self.model, len(vars), _vars, fml.ast), self.ctx)
6907

◆ project_with_witness()

project_with_witness ( self,
vars,
fml )
Perform model-based projection, but also include realizer terms for the projected variables

Definition at line 6908 of file z3py.py.

6908 def project_with_witness(self, vars, fml):
6909 """Perform model-based projection, but also include realizer terms for the projected variables"""
6910 ctx = self.ctx.ref()
6911 _vars = (Ast * len(vars))()
6912 for i in range(len(vars)):
6913 _vars[i] = vars[i].as_ast()
6914 defs = AstMap()
6915 result = Z3_qe_model_project_with_witness(ctx, self.model, len(vars), _vars, fml.ast, defs.map)
6916 result = _to_expr_ref(result, self.ctx)
6917 return result, defs
6918
6919

◆ sexpr()

sexpr ( self)
Return a textual representation of the s-expression representing the model.

Definition at line 6597 of file z3py.py.

6597 def sexpr(self):
6598 """Return a textual representation of the s-expression representing the model."""
6599 return Z3_model_to_string(self.ctx.ref(), self.model)
6600
Z3_string Z3_API Z3_model_to_string(Z3_context c, Z3_model m)
Convert the given model into a string.

◆ sorts()

sorts ( self)
Return all uninterpreted sorts that have an interpretation in the model `self`.

>>> A = DeclareSort('A')
>>> B = DeclareSort('B')
>>> a1, a2 = Consts('a1 a2', A)
>>> b1, b2 = Consts('b1 b2', B)
>>> s = Solver()
>>> s.add(a1 != a2, b1 != b2)
>>> s.check()
sat
>>> m = s.model()
>>> m.sorts()
[A, B]

Definition at line 6765 of file z3py.py.

6765 def sorts(self):
6766 """Return all uninterpreted sorts that have an interpretation in the model `self`.
6767
6768 >>> A = DeclareSort('A')
6769 >>> B = DeclareSort('B')
6770 >>> a1, a2 = Consts('a1 a2', A)
6771 >>> b1, b2 = Consts('b1 b2', B)
6772 >>> s = Solver()
6773 >>> s.add(a1 != a2, b1 != b2)
6774 >>> s.check()
6775 sat
6776 >>> m = s.model()
6777 >>> m.sorts()
6778 [A, B]
6779 """
6780 return [self.get_sort(i) for i in range(self.num_sorts())]
6781

◆ translate()

translate ( self,
target )
Translate `self` to the context `target`. That is, return a copy of `self` in the context `target`.

Definition at line 6888 of file z3py.py.

6888 def translate(self, target):
6889 """Translate `self` to the context `target`. That is, return a copy of `self` in the context `target`.
6890 """
6891 if z3_debug():
6892 _z3_assert(isinstance(target, Context), "argument must be a Z3 context")
6893 model = Z3_model_translate(self.ctx.ref(), self.model, target.ref())
6894 return ModelRef(model, target)
6895
Z3_model Z3_API Z3_model_translate(Z3_context c, Z3_model m, Z3_context dst)
translate model from context c to context dst.

Referenced by __copy__(), and __deepcopy__().

◆ update_value()

update_value ( self,
x,
value )
Update the interpretation of a constant

Definition at line 6866 of file z3py.py.

6866 def update_value(self, x, value):
6867 """Update the interpretation of a constant"""
6868 if is_expr(x):
6869 x = x.decl()
6870 if is_func_decl(x) and x.arity() != 0 and isinstance(value, FuncInterp):
6871 fi1 = value.f
6872 fi2 = Z3_add_func_interp(x.ctx_ref(), self.model, x.ast, value.else_value().ast);
6873 fi2 = FuncInterp(fi2, x.ctx)
6874 for i in range(value.num_entries()):
6875 e = value.entry(i)
6876 n = Z3_func_entry_get_num_args(x.ctx_ref(), e.entry)
6877 v = AstVector()
6878 for j in range(n):
6879 v.push(e.arg_value(j))
6880 val = Z3_func_entry_get_value(x.ctx_ref(), e.entry)
6881 Z3_func_interp_add_entry(x.ctx_ref(), fi2.f, v.vector, val)
6882 return
6883 if not is_func_decl(x) or x.arity() != 0:
6884 raise Z3Exception("Expecting 0-ary function or constant expression")
6885 value = _py2expr(value)
6886 Z3_add_const_interp(x.ctx_ref(), self.model, x.ast, value.ast)
6887
Z3_func_interp Z3_API Z3_add_func_interp(Z3_context c, Z3_model m, Z3_func_decl f, Z3_ast default_value)
Create a fresh func_interp object, add it to a model for a specified function. It has reference count...
unsigned Z3_API Z3_func_entry_get_num_args(Z3_context c, Z3_func_entry e)
Return the number of arguments in a Z3_func_entry object.
Z3_ast Z3_API Z3_func_entry_get_value(Z3_context c, Z3_func_entry e)
Return the value of this point.
void Z3_API Z3_add_const_interp(Z3_context c, Z3_model m, Z3_func_decl f, Z3_ast a)
Add a constant interpretation.
void Z3_API Z3_func_interp_add_entry(Z3_context c, Z3_func_interp fi, Z3_ast_vector args, Z3_ast value)
add a function entry to a function interpretation.

Field Documentation

◆ ctx

◆ model