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What is the normal procedure of z3 handle axiom with quantifier?
I've read some part of this book, this tutorial, and this tutorial, and would like to find out how Z3 handles quantified formula.
No matter with the book or in the web, it would like to map the term (...
-1
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1
answer
45
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write encodings in Z3 Solver python for string functions like concat
write encodings in z3 solver python for string functions like concat, charAt, contains
Like for concat I have
formula= ForAll([fs1, fs2],
Implies(
...
1
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3
answers
922
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Why cant we check satisfiability in polynomial time by converting the expression to CNF?
we know that any expression can be converted to a CNF in linear time where the CNF result is not 'logically equivalent' to the original expression but the 'satisfiability' is invariant meaning that ...
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1
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155
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How can I perform validity of ∃∀.φ, if I use quantifier elimination for ∀.φ and get φ'? I hypothetise ∃φ' solves satisfiability, not validity
I want to check validity of a formula with the following quantifier alternation: ∃∀.φ
Do I check validity of this formula if I solve Exists(exist_vars, ForAll(forall_vars, Phi)) in Z3Py? What is the ...
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2
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432
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Specifying modular arithmetic conditions in Z3
How do I specify a modular artithmetic condition such as
f1 := (b[0]*2^0 + b[1]*2^1 + b[2]*2^2 + b[3]*2^3 + b[4]*2^4 ≡ 1 (mod 5)) ∨
(b[0]*2^0 + b[1]*2^1 + b[2]*2^2 + b[3]*2^3 + b[4]*2^4 ≡ 2 (...
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4
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789
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Example of unique 3sat solution
I am searching for 3sat problems having unique solution. Till now, I only found one site https://www.cs.ubc.ca/~hoos/SATLIB/benchm.html
There are good examples of 3sat instance on that site but the ...
2
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1
answer
257
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z3 solver using Sympy symbols
I'm trying to use Z3 to determine if an expression is satisfiable.I have created all equations that I want to use it as constraints using SymPy and the variables are Symbols.
the equations for example
...
2
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1
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83
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What does a model mean in a universally quantified formula? Is it a function?
Consider these two formulae:
Exists y. Forall x. (y>x), which is unsat.
Forall x. Exists y. (y>x), which is sat.
Note that we cannot find "models" for the sat formula, e.g., using Z3 it ...
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1
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364
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In Z3, I cannot understand result of quantifier elimination of Exists y. Forall x. (x>=2) => ((y>1) /\ (y<=x))
In Z3-Py, I am performing quantifier elimination (QE) over the following formulae:
Exists y. Forall x. (x>=2) => ((y>1) /\ (y<=x))
Forall x. Exists y. (x>=2) => ((y>1) /\ (y<=...
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1
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325
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Some questions about dReal: delta-satisfiability, parameter with 0.0, doing the same in Z3 and obtaining sat/unsat result
I am starting with dReal and I have a set of questions about it.
These questions are based on the tutorial we can find in https://github.com/dreal/dreal4, section "Python bindings", with the ...
1
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1
answer
250
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How can I specify a function in Minizinc that returns True if a boolean array contains at least one True element, and False otherwise?
The problem
In a Minizinc model where I want to minimize a linear cost function, I can say the following:
set of int: foos = 1..8;
set of int: bars = 1..5;
array[foos] of float: cost;
array[foos, ...
0
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1
answer
130
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Derivation in the Resolution Proof System
The clauses of our problem: {x,y},{x,z},{y,z},{¬x,¬y},{¬x,¬z},{¬y,¬z}
How can we conclude from these clauses to {}?
I can see that this cannot be satisfied, but I am unable to find a solution in the ...
0
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1
answer
226
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Dimacs cnf expression not satisfiable, why?
I am a new cs student and I have a hard time understanding satisfiability fully.
I have made 2 expressions for a SAT solver.
Seperately, they are satisfiable, but together they're not.
I don't ...
0
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1
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89
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Satisfiability 3-towers assignment
I have stared at this assignment for far too long now and I simply don't understand what I am supposed to do exactly. We are given a 3x3 chess board and have to produce some propositonal clauses to ...
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2
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487
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Converting circuit benchmark to CNF formula to use to solve with SAT solvers
Is there any tool that can convert circuit benchmarks (ISCAS) to CNF so that it can be used in SAT solver? The main goal is to find some input patterns for the circuit which will give some predefined ...