docs: Fix ModSwitch, Update docs

sp301415 · Jun 7, 2024 · a08aaa7 · a08aaa7
1 parent ecf6c08
commit a08aaa7
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Showing 3 changed files with 8 additions and 9 deletions.
diff --git a/README.md b/README.md
@@ -139,10 +139,10 @@ fmt.Println(dec.DecryptLWEBool(ctOut)) // false
 
 ## Benchmarks
 All results were measured from Intel i5-13400F, with roughly equivalent parameters.
-|Operation|TFHE-go|TFHE-rs (v0.6.0)|
+|Operation|TFHE-go|TFHE-rs (v0.6.1)|
 |---------|-------|-------|
-|Gate Bootstrapping|8.22ms|8.82ms|
-|Programmable Bootstrapping (6 bits)|26.78ms|72.93ms|
+|Gate Bootstrapping|8.13ms|8.45ms|
+|Programmable Bootstrapping (6 bits)|26.30ms|69.22ms|
 
 ## Security
 TFHE-go has not been audited or reviewed by security experts, and may contain critical vulnerabilities. Use at your own risk. See [SECURITY](https://github.com/sp301415/tfhe-go/blob/master/SECURITY.md) for more details.

diff --git a/mktfhe/bootstrap.go b/mktfhe/bootstrap.go
@@ -80,7 +80,7 @@ func (e *Evaluator[T]) BlindRotate(ct LWECiphertext[T], lut tfhe.LookUpTable[T])
 	return ctOut
 }
 
-// BlindRotateAssign assigns the blind rotation of LWE ciphertext with respect to LUT to ctOut.
+// BlindRotateAssign computes the blind rotation of LWE ciphertext with respect to LUT and writes it to ctOut.
 func (e *Evaluator[T]) BlindRotateAssign(ct LWECiphertext[T], lut tfhe.LookUpTable[T], ctOut GLWECiphertext[T]) {
 	ctOut.Clear()
 
@@ -106,7 +106,7 @@ func (e *Evaluator[T]) BlindRotateParallel(ct LWECiphertext[T], lut tfhe.LookUpT
 	return ctOut
 }
 
-// BlindRotateParallelAssign assigns the blind rotation of LWE ciphertext with respect to LUT to ctOut in parallel.
+// BlindRotateParallelAssign computes the blind rotation of LWE ciphertext with respect to LUT and writes it to ctOut in parallel.
 func (e *Evaluator[T]) BlindRotateParallelAssign(ct LWECiphertext[T], lut tfhe.LookUpTable[T], ctOut GLWECiphertext[T]) {
 	ctOut.Clear()
 

diff --git a/tfhe/bootstrap.go b/tfhe/bootstrap.go
@@ -120,10 +120,9 @@ func (e *Evaluator[T]) BootstrapLUTAssign(ct LWECiphertext[T], lut LookUpTable[T
 	}
 }
 
-// ModSwitch computes x2N = round(2N * x / Q)
-// and returns x2N as an unsigned representation.
+// ModSwitch switches the modulus of x from Q to 2 * LookUpTableSize.
 func (e *Evaluator[T]) ModSwitch(x T) int {
-	return int(math.Round(e.modSwitchConstant * float64(x)))
+	return int(math.Round(e.modSwitchConstant*float64(x))) % (2 * e.Parameters.lookUpTableSize)
 }
 
 // BlindRotate returns the blind rotation of LWE ciphertext with respect to LUT.
@@ -133,7 +132,7 @@ func (e *Evaluator[T]) BlindRotate(ct LWECiphertext[T], lut LookUpTable[T]) GLWE
 	return ctOut
 }
 
-// BlindRotateAssign computes the blind rotation of LWE ciphertext with respect to LUT.
+// BlindRotateAssign computes the blind rotation of LWE ciphertext with respect to LUT, and writes it to ctOut.
 func (e *Evaluator[T]) BlindRotateAssign(ct LWECiphertext[T], lut LookUpTable[T], ctOut GLWECiphertext[T]) {
 	switch {
 	case e.Parameters.lookUpTableSize > e.Parameters.polyDegree: