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[英]'builtin_function_or_method' object is not iterable' error in python search?
[英]In Z3-Python, I get "builtin_function_or_method' object is not iterable" when performing model search
我正在探索在 Z3 (Python) 中執行 SAT 求解的快速方法。 為此,我試圖模仿https://theory.stanford.edu/~nikolaj/programmingz3.html#sec-blocking-evaluations的第 5.1 章的結果。
我正在使用的代碼如下:
def block_modelT(s, terms): #I used the name 'block_modelT' so as not to use 'block_model'
m = s.model()
s.add(Or([t != m.eval(t) for t in terms]))
def all_smt(s, terms):
while sat == s.check():
print(s.model())
block_modelT(s, terms)
因此,我執行它:
pip install z3-solver
from z3 import *
x, y, z = Bools('x y z')
vars = [x,y,z]
phi_0 = x #ignore that I call them phi: it is because I am used to do it like that for predicates (i.e. literals) of other theories: e.g., if x is Int, then phi_0 = (x>0)
phi_1 = y
phi_2 = z
phi = And(phi_0, Or(phi_1, phi_2))
all_smt(s, vars)
並得到以下錯誤:
1 def block_modelT(s, terms):
2 m = s.model()
----> 3 s.add(Or([t != m.eval(t) for t in terms]))
TypeError: 'builtin_function_or_method' object is not iterable
有什么幫助嗎?
編輯:
問題已經解決,所以我終於嘗試下一段代碼:
def all_smt(s, initial_terms):
def block_term(s, m, t):
s.add(t != m.eval(t))
def fix_term(s, m, t):
s.add(t == m.eval(t))
def all_smt_rec(terms):
if sat == s.check():
m = s.model()
yield m
for i in range(len(terms)):
s.push()
block_term(s, m, terms[i])
for j in range(i):
fix_term(s, m, terms[j])
for m in all_smt_rec(terms[i:]):
yield m
s.pop()
for m in all_smt_rec(list(initial_terms)):
yield m
我執行它: all_smt(s, varss) #has the same name
。 並<generator object all_smt at 0x7...
而不是有效分配(即模型)。 怎樣才能得到正確答案[z = False, y = True, x = True], [z = True, x = True]
? 我嘗試了print
和return
。
您的程序沒有定義s
; 而且您還沒有向其中添加公式。 以下對我有用:
from z3 import *
def block_modelT(s, terms): #I used the name 'block_modelT' so as not to use 'block_model'
m = s.model()
s.add(Or([t != m.eval(t) for t in terms]))
def all_smt(s, terms):
while sat == s.check():
print(s.model())
block_modelT(s, terms)
x, y, z = Bools('x y z')
vars = [x,y,z]
phi_0 = x #ignore that I call them phi: it is because I am used to do it like that for predicates (i.e. literals) of other theories: e.g., if x is Int, then phi_0 = (x>0)
phi_1 = y
phi_2 = z
phi = And(phi_0, Or(phi_1, phi_2))
s = Solver()
s.add(phi)
all_smt(s, vars)
這打印:
[z = False, y = True, x = True]
[z = True, x = True]
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