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Remove conditional negation implementation from AllocatedNum.

This commit is contained in:
Sean Bowe 2018-02-20 16:41:33 -07:00
parent c89d47bb07
commit 4fa73efc1e
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GPG Key ID: 95684257D8F8B031
1 changed files with 0 additions and 133 deletions
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133
src/circuit/num.rs
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@ -312,38 +312,6 @@ impl<E: Engine> AllocatedNum<E> {
Ok((c, d))
}
pub fn conditionally_negate<CS>(
&self,
mut cs: CS,
condition: &Boolean
) -> Result<Self, SynthesisError>
where CS: ConstraintSystem<E>
{
let r = Self::alloc(
cs.namespace(|| "conditional negation result"),
|| {
let mut tmp = *self.value.get()?;
if *condition.get_value().get()? {
tmp.negate();
}
Ok(tmp)
}
)?;
// (1-c)(x) + (c)(-x) = r
// x - 2cx = r
// (2x) * (c) = x - r
cs.enforce(
|| "conditional negation",
|lc| lc + self.variable + self.variable,
|_| condition.lc(CS::one(), E::Fr::one()),
|lc| lc + self.variable - r.variable
);
Ok(r)
}
pub fn get_value(&self) -> Option<E::Fr> {
self.value
}
@ -433,107 +401,6 @@ mod test {
}
}
#[test]
fn test_num_conditional_negation() {
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::constant(true);
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
let mut negone = Fr::one();
negone.negate();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == negone);
assert!(n2.value.unwrap() == negone);
cs.set("conditional negation result/num", Fr::from_str("1").unwrap());
assert!(!cs.is_satisfied());
}
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::constant(false);
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == Fr::one());
assert!(n2.value.unwrap() == Fr::one());
cs.set("conditional negation result/num", Fr::from_str("2").unwrap());
assert!(!cs.is_satisfied());
}
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::from(
AllocatedBit::alloc(cs.namespace(|| "condition"), Some(true)).unwrap()
);
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
let mut negone = Fr::one();
negone.negate();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == negone);
assert!(n2.value.unwrap() == negone);
cs.set("conditional negation result/num", Fr::from_str("1").unwrap());
assert!(!cs.is_satisfied());
}
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::from(
AllocatedBit::alloc(cs.namespace(|| "condition"), Some(false)).unwrap()
);
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == Fr::one());
assert!(n2.value.unwrap() == Fr::one());
cs.set("conditional negation result/num", Fr::from_str("2").unwrap());
assert!(!cs.is_satisfied());
}
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::from(
AllocatedBit::alloc(cs.namespace(|| "condition"), Some(false)).unwrap()
).not();
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
let mut negone = Fr::one();
negone.negate();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == negone);
assert!(n2.value.unwrap() == negone);
cs.set("conditional negation result/num", Fr::from_str("1").unwrap());
assert!(!cs.is_satisfied());
}
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one())).unwrap();
let b = Boolean::from(
AllocatedBit::alloc(cs.namespace(|| "condition"), Some(true)).unwrap()
).not();
let n2 = n.conditionally_negate(&mut cs, &b).unwrap();
assert!(cs.is_satisfied());
assert!(cs.get("conditional negation result/num") == Fr::one());
assert!(n2.value.unwrap() == Fr::one());
cs.set("conditional negation result/num", Fr::from_str("2").unwrap());
assert!(!cs.is_satisfied());
}
}
#[test]
fn test_num_nonzero() {
{