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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 6983 of file z3py.py.

Constructor & Destructor Documentation

◆ __init__()

__init__ ( self,
m,
ctx )

Definition at line 6986 of file z3py.py.

6986 def __init__(self, m, ctx):
6987 assert ctx is not None
6988 self.model = m
6989 self.ctx = ctx
6990 Z3_model_inc_ref(self.ctx.ref(), self.model)
6991
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 6992 of file z3py.py.

6992 def __del__(self):
6993 if self.ctx.ref() is not None and Z3_model_dec_ref is not None:
6994 Z3_model_dec_ref(self.ctx.ref(), self.model)
6995
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 7324 of file z3py.py.

7324 def __copy__(self):
7325 return self.translate(self.ctx)
7326

◆ __deepcopy__()

__deepcopy__ ( self,
memo = {} )

Definition at line 7327 of file z3py.py.

7327 def __deepcopy__(self, memo={}):
7328 return self.translate(self.ctx)
7329
7330

◆ __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 7204 of file z3py.py.

7204 def __getitem__(self, idx):
7205 """If `idx` is an integer, then the declaration at position `idx` in the model `self` is returned.
7206 If `idx` is a declaration, then the actual interpretation is returned.
7207
7208 The elements can be retrieved using position or the actual declaration.
7209
7210 >>> f = Function('f', IntSort(), IntSort())
7211 >>> x = Int('x')
7212 >>> s = Solver()
7213 >>> s.add(x > 0, x < 2, f(x) == 0)
7214 >>> s.check()
7215 sat
7216 >>> m = s.model()
7217 >>> len(m)
7218 2
7219 >>> m[0]
7220 x
7221 >>> m[1]
7222 f
7223 >>> m[x]
7224 1
7225 >>> m[f]
7226 [else -> 0]
7227 >>> for d in m: print("%s -> %s" % (d, m[d]))
7228 x -> 1
7229 f -> [else -> 0]
7230 """
7231 if _is_int(idx):
7232 if idx < 0:
7233 idx += len(self)
7234 if idx < 0 or idx >= len(self):
7235 raise IndexError
7236 num_consts = Z3_model_get_num_consts(self.ctx.ref(), self.model)
7237 if (idx < num_consts):
7238 return FuncDeclRef(Z3_model_get_const_decl(self.ctx.ref(), self.model, idx), self.ctx)
7239 else:
7240 return FuncDeclRef(Z3_model_get_func_decl(self.ctx.ref(), self.model, idx - num_consts), self.ctx)
7241 if isinstance(idx, FuncDeclRef):
7242 return self.get_interp(idx)
7243 if is_const(idx):
7244 return self.get_interp(idx.decl())
7245 if isinstance(idx, SortRef):
7246 return self.get_universe(idx)
7247 if z3_debug():
7248 _z3_assert(False, "Integer, Z3 declaration, or Z3 constant expected. Use model.eval instead for complicated expressions")
7249 return None
7250
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 7060 of file z3py.py.

7060 def __len__(self):
7061 """Return the number of constant and function declarations in the model `self`.
7062
7063 >>> f = Function('f', IntSort(), IntSort())
7064 >>> x = Int('x')
7065 >>> s = Solver()
7066 >>> s.add(x > 0, f(x) != x)
7067 >>> s.check()
7068 sat
7069 >>> m = s.model()
7070 >>> len(m)
7071 2
7072 """
7073 num_consts = int(Z3_model_get_num_consts(self.ctx.ref(), self.model))
7074 num_funcs = int(Z3_model_get_num_funcs(self.ctx.ref(), self.model))
7075 return num_consts + num_funcs
7076
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 6996 of file z3py.py.

6996 def __repr__(self):
6997 return obj_to_string(self)
6998

◆ 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 7251 of file z3py.py.

7251 def decls(self):
7252 """Return a list with all symbols that have an interpretation in the model `self`.
7253 >>> f = Function('f', IntSort(), IntSort())
7254 >>> x = Int('x')
7255 >>> s = Solver()
7256 >>> s.add(x > 0, x < 2, f(x) == 0)
7257 >>> s.check()
7258 sat
7259 >>> m = s.model()
7260 >>> m.decls()
7261 [x, f]
7262 """
7263 r = []
7264 for i in range(Z3_model_get_num_consts(self.ctx.ref(), self.model)):
7265 r.append(FuncDeclRef(Z3_model_get_const_decl(self.ctx.ref(), self.model, i), self.ctx))
7266 for i in range(Z3_model_get_num_funcs(self.ctx.ref(), self.model)):
7267 r.append(FuncDeclRef(Z3_model_get_func_decl(self.ctx.ref(), self.model, i), self.ctx))
7268 return r
7269

◆ 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 7003 of file z3py.py.

7003 def eval(self, t, model_completion=False):
7004 """Evaluate the expression `t` in the model `self`.
7005 If `model_completion` is enabled, then a default interpretation is automatically added
7006 for symbols that do not have an interpretation in the model `self`.
7007
7008 >>> x = Int('x')
7009 >>> s = Solver()
7010 >>> s.add(x > 0, x < 2)
7011 >>> s.check()
7012 sat
7013 >>> m = s.model()
7014 >>> m.eval(x + 1)
7015 2
7016 >>> m.eval(x == 1)
7017 True
7018 >>> y = Int('y')
7019 >>> m.eval(y + x)
7020 1 + y
7021 >>> m.eval(y)
7022 y
7023 >>> m.eval(y, model_completion=True)
7024 0
7025 >>> # Now, m contains an interpretation for y
7026 >>> m.eval(y + x)
7027 1
7028 """
7029 r = (Ast * 1)()
7030 if Z3_model_eval(self.ctx.ref(), self.model, t.as_ast(), model_completion, r):
7031 return _to_expr_ref(r[0], self.ctx)
7032 raise Z3Exception("failed to evaluate expression in the model")
7033
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 7034 of file z3py.py.

7034 def evaluate(self, t, model_completion=False):
7035 """Alias for `eval`.
7036
7037 >>> x = Int('x')
7038 >>> s = Solver()
7039 >>> s.add(x > 0, x < 2)
7040 >>> s.check()
7041 sat
7042 >>> m = s.model()
7043 >>> m.evaluate(x + 1)
7044 2
7045 >>> m.evaluate(x == 1)
7046 True
7047 >>> y = Int('y')
7048 >>> m.evaluate(y + x)
7049 1 + y
7050 >>> m.evaluate(y)
7051 y
7052 >>> m.evaluate(y, model_completion=True)
7053 0
7054 >>> # Now, m contains an interpretation for y
7055 >>> m.evaluate(y + x)
7056 1
7057 """
7058 return self.eval(t, model_completion)
7059

◆ 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 7077 of file z3py.py.

7077 def get_interp(self, decl):
7078 """Return the interpretation for a given declaration or constant.
7079
7080 >>> f = Function('f', IntSort(), IntSort())
7081 >>> x = Int('x')
7082 >>> s = Solver()
7083 >>> s.add(x > 0, x < 2, f(x) == 0)
7084 >>> s.check()
7085 sat
7086 >>> m = s.model()
7087 >>> m[x]
7088 1
7089 >>> m[f]
7090 [else -> 0]
7091 """
7092 if z3_debug():
7093 _z3_assert(isinstance(decl, FuncDeclRef) or is_const(decl), "Z3 declaration expected")
7094 if is_const(decl):
7095 decl = decl.decl()
7096 try:
7097 if decl.arity() == 0:
7098 _r = Z3_model_get_const_interp(self.ctx.ref(), self.model, decl.ast)
7099 if _r.value is None:
7100 return None
7101 r = _to_expr_ref(_r, self.ctx)
7102 if is_as_array(r):
7103 fi = self.get_interp(get_as_array_func(r))
7104 if fi is None:
7105 return fi
7106 e = fi.else_value()
7107 if e is None:
7108 return fi
7109 if fi.arity() != 1:
7110 return fi
7111 srt = decl.range()
7112 dom = srt.domain()
7113 e = K(dom, e)
7114 i = 0
7115 sz = fi.num_entries()
7116 n = fi.arity()
7117 while i < sz:
7118 fe = fi.entry(i)
7119 e = Store(e, fe.arg_value(0), fe.value())
7120 i += 1
7121 return e
7122 else:
7123 return r
7124 else:
7125 return FuncInterp(Z3_model_get_func_interp(self.ctx.ref(), self.model, decl.ast), self.ctx)
7126 except Z3Exception:
7127 return None
7128
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 7144 of file z3py.py.

7144 def get_sort(self, idx):
7145 """Return the uninterpreted sort at position `idx` < self.num_sorts().
7146
7147 >>> A = DeclareSort('A')
7148 >>> B = DeclareSort('B')
7149 >>> a1, a2 = Consts('a1 a2', A)
7150 >>> b1, b2 = Consts('b1 b2', B)
7151 >>> s = Solver()
7152 >>> s.add(a1 != a2, b1 != b2)
7153 >>> s.check()
7154 sat
7155 >>> m = s.model()
7156 >>> m.num_sorts()
7157 2
7158 >>> m.get_sort(0)
7159 A
7160 >>> m.get_sort(1)
7161 B
7162 """
7163 if idx >= self.num_sorts():
7164 raise IndexError
7165 return _to_sort_ref(Z3_model_get_sort(self.ctx.ref(), self.model, idx), self.ctx)
7166
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!0, A!val!1]

Definition at line 7184 of file z3py.py.

7184 def get_universe(self, s):
7185 """Return the interpretation for the uninterpreted sort `s` in the model `self`.
7186
7187 >>> A = DeclareSort('A')
7188 >>> a, b = Consts('a b', A)
7189 >>> s = Solver()
7190 >>> s.add(a != b)
7191 >>> s.check()
7192 sat
7193 >>> m = s.model()
7194 >>> m.get_universe(A)
7195 [A!val!0, A!val!1]
7196 """
7197 if z3_debug():
7198 _z3_assert(isinstance(s, SortRef), "Z3 sort expected")
7199 try:
7200 return AstVector(Z3_model_get_sort_universe(self.ctx.ref(), self.model, s.ast), self.ctx)
7201 except Z3Exception:
7202 return None
7203
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 7129 of file z3py.py.

7129 def num_sorts(self):
7130 """Return the number of uninterpreted sorts that contain an interpretation in the model `self`.
7131
7132 >>> A = DeclareSort('A')
7133 >>> a, b = Consts('a b', A)
7134 >>> s = Solver()
7135 >>> s.add(a != b)
7136 >>> s.check()
7137 sat
7138 >>> m = s.model()
7139 >>> m.num_sorts()
7140 1
7141 """
7142 return int(Z3_model_get_num_sorts(self.ctx.ref(), self.model))
7143
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 7300 of file z3py.py.

7300 def project(self, vars, fml):
7301 """Perform model-based projection on fml with respect to vars.
7302 Assume that the model satisfies fml. Then compute a projection fml_p, such
7303 that vars do not occur free in fml_p, fml_p is true in the model and
7304 fml_p => exists vars . fml
7305 """
7306 ctx = self.ctx.ref()
7307 _vars = (Ast * len(vars))()
7308 for i in range(len(vars)):
7309 _vars[i] = vars[i].as_ast()
7310 return _to_expr_ref(Z3_qe_model_project(ctx, self.model, len(vars), _vars, fml.ast), self.ctx)
7311

◆ 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 7312 of file z3py.py.

7312 def project_with_witness(self, vars, fml):
7313 """Perform model-based projection, but also include realizer terms for the projected variables"""
7314 ctx = self.ctx.ref()
7315 _vars = (Ast * len(vars))()
7316 for i in range(len(vars)):
7317 _vars[i] = vars[i].as_ast()
7318 defs = AstMap()
7319 result = Z3_qe_model_project_with_witness(ctx, self.model, len(vars), _vars, fml.ast, defs.map)
7320 result = _to_expr_ref(result, self.ctx)
7321 return result, defs
7322
7323

◆ sexpr()

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

Definition at line 6999 of file z3py.py.

6999 def sexpr(self):
7000 """Return a textual representation of the s-expression representing the model."""
7001 return Z3_model_to_string(self.ctx.ref(), self.model)
7002
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 7167 of file z3py.py.

7167 def sorts(self):
7168 """Return all uninterpreted sorts that have an interpretation in the model `self`.
7169
7170 >>> A = DeclareSort('A')
7171 >>> B = DeclareSort('B')
7172 >>> a1, a2 = Consts('a1 a2', A)
7173 >>> b1, b2 = Consts('b1 b2', B)
7174 >>> s = Solver()
7175 >>> s.add(a1 != a2, b1 != b2)
7176 >>> s.check()
7177 sat
7178 >>> m = s.model()
7179 >>> m.sorts()
7180 [A, B]
7181 """
7182 return [self.get_sort(i) for i in range(self.num_sorts())]
7183

◆ translate()

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

Definition at line 7292 of file z3py.py.

7292 def translate(self, target):
7293 """Translate `self` to the context `target`. That is, return a copy of `self` in the context `target`.
7294 """
7295 if z3_debug():
7296 _z3_assert(isinstance(target, Context), "argument must be a Z3 context")
7297 model = Z3_model_translate(self.ctx.ref(), self.model, target.ref())
7298 return ModelRef(model, target)
7299
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 7270 of file z3py.py.

7270 def update_value(self, x, value):
7271 """Update the interpretation of a constant"""
7272 if is_expr(x):
7273 x = x.decl()
7274 if is_func_decl(x) and x.arity() != 0 and isinstance(value, FuncInterp):
7275 fi1 = value.f
7276 fi2 = Z3_add_func_interp(x.ctx_ref(), self.model, x.ast, value.else_value().ast);
7277 fi2 = FuncInterp(fi2, x.ctx)
7278 for i in range(value.num_entries()):
7279 e = value.entry(i)
7280 n = Z3_func_entry_get_num_args(x.ctx_ref(), e.entry)
7281 v = AstVector()
7282 for j in range(n):
7283 v.push(e.arg_value(j))
7284 val = Z3_func_entry_get_value(x.ctx_ref(), e.entry)
7285 Z3_func_interp_add_entry(x.ctx_ref(), fi2.f, v.vector, val)
7286 return
7287 if not is_func_decl(x) or x.arity() != 0:
7288 raise Z3Exception("Expecting 0-ary function or constant expression")
7289 value = _py2expr(value)
7290 Z3_add_const_interp(x.ctx_ref(), self.model, x.ast, value.ast)
7291
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