Update Modify

itsubaki · Jan 13, 2025 · 4714af2 · 4714af2
1 parent 2ef7377
commit 4714af2
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Showing 3 changed files with 98 additions and 35 deletions.
diff --git a/visitor/gate.go b/visitor/gate.go
@@ -6,9 +6,9 @@ import (
 	"github.com/itsubaki/q/quantum/gate"
 )
 
-// AddControlled returns a controlled-u gate with control bit.
+// Controlled returns a controlled-u gate with control bit.
 // u is a (2**n x 2**n) unitary matrix and returns a (2**n x 2**n) matrix.
-func AddControlled(u matrix.Matrix, c []int) matrix.Matrix {
+func Controlled(u matrix.Matrix, c []int) matrix.Matrix {
 	d, _ := u.Dimension()
 	n := number.Log2(d)
 	g := gate.I(n)
@@ -31,6 +31,14 @@ func AddControlled(u matrix.Matrix, c []int) matrix.Matrix {
 	return g
 }
 
+// NegControlled returns a controlled-u gate with control bit.
+// u is a (2**n x 2**n) unitary matrix and returns a (2**n x 2**n) matrix.
+func NegControlled(u matrix.Matrix, n int, c []int) matrix.Matrix {
+	x := gate.TensorProduct(gate.X(), n, c)
+	cu := Controlled(u, c)
+	return matrix.Apply(x, cu, x)
+}
+
 func Pow(u matrix.Matrix, p float64) matrix.Matrix {
 	// TODO: support float type
 	return matrix.ApplyN(u, int(p))

diff --git a/visitor/gate_test.go b/visitor/gate_test.go
@@ -9,7 +9,7 @@ import (
 	"github.com/itsubaki/qasm/visitor"
 )
 
-func TestAddControlled(t *testing.T) {
+func TestControlled(t *testing.T) {
 	u := gate.U(rand.Float64(), rand.Float64(), rand.Float64())
 
 	cases := []struct {
@@ -70,7 +70,63 @@ func TestAddControlled(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		got := visitor.AddControlled(c.in, []int{c.bit})
+		got := visitor.Controlled(c.in, []int{c.bit})
+		if !got.Equals(c.want) {
+			t.Fail()
+		}
+	}
+}
+
+func TestNegControlled(t *testing.T) {
+	cases := []struct {
+		in     matrix.Matrix
+		want   matrix.Matrix
+		n, bit int
+	}{
+		{
+			in: gate.TensorProduct(gate.X(), 2, []int{1}),
+			want: matrix.Apply(
+				gate.TensorProduct(gate.X(), 2, []int{0}),
+				gate.ControlledNot(2, []int{0}, 1),
+				gate.TensorProduct(gate.X(), 2, []int{0}),
+			),
+			n:   2,
+			bit: 0,
+		},
+		{
+			in: gate.TensorProduct(gate.X(), 2, []int{0}),
+			want: matrix.Apply(
+				gate.TensorProduct(gate.X(), 2, []int{1}),
+				gate.ControlledNot(2, []int{1}, 0),
+				gate.TensorProduct(gate.X(), 2, []int{1}),
+			),
+			n:   2,
+			bit: 1,
+		},
+		{
+			in: gate.ControlledNot(3, []int{0}, 2),
+			want: matrix.Apply(
+				gate.TensorProduct(gate.X(), 3, []int{1}),
+				gate.ControlledNot(3, []int{0, 1}, 2),
+				gate.TensorProduct(gate.X(), 3, []int{1}),
+			),
+			n:   3,
+			bit: 1,
+		},
+		{
+			in: gate.ControlledNot(3, []int{0}, 1),
+			want: matrix.Apply(
+				gate.TensorProduct(gate.X(), 3, []int{2}),
+				gate.ControlledNot(3, []int{0, 2}, 1),
+				gate.TensorProduct(gate.X(), 3, []int{2}),
+			),
+			n:   3,
+			bit: 2,
+		},
+	}
+
+	for _, c := range cases {
+		got := visitor.NegControlled(c.in, c.n, []int{c.bit})
 		if !got.Equals(c.want) {
 			t.Fail()
 		}

diff --git a/visitor/visitor.go b/visitor/visitor.go
@@ -311,35 +311,6 @@ func (v *Visitor) Params(xlist parser.IExpressionListContext) ([]float64, error)
 	return params, nil
 }
 
-func (v *Visitor) Modify(u matrix.Matrix, qargs [][]q.Qubit, modifier []parser.IGateModifierContext) (matrix.Matrix, error) {
-	for i, mod := range modifier {
-		switch {
-		case mod.CTRL() != nil:
-			u = AddControlled(u, q.Index(qargs[i]...))
-		case mod.NEGCTRL() != nil:
-			x := gate.TensorProduct(gate.X(), v.qsim.NumberOfBit(), q.Index(qargs[i]...))
-			u = AddControlled(u, q.Index(qargs[i]...))
-			u = matrix.Apply(x, u, x)
-		case mod.INV() != nil:
-			u = u.Dagger()
-		case mod.POW() != nil:
-			var p float64
-			switch n := v.Visit(mod).(type) {
-			case float64:
-				p = n
-			case int64:
-				p = float64(n)
-			default:
-				return nil, fmt.Errorf("pow=%v: %w", n, ErrUnexpected)
-			}
-
-			u = Pow(u, p)
-		}
-	}
-
-	return u, nil
-}
-
 func (v *Visitor) Builtin(ctx *parser.GateCallStatementContext) (matrix.Matrix, bool, error) {
 	if ctx.GPHASE() != nil {
 		params, err := v.Params(ctx.ExpressionList())
@@ -368,7 +339,7 @@ func (v *Visitor) Builtin(ctx *parser.GateCallStatementContext) (matrix.Matrix,
 		u = gate.TensorProduct(u, n, q.Index(flatten(qargs)...))
 
 		// modify
-		u, err = v.Modify(u, qargs, ctx.AllGateModifier())
+		u, err = v.Modify(u, n, qargs, ctx.AllGateModifier())
 		if err != nil {
 			return nil, false, fmt.Errorf("modify: %w", err)
 		}
@@ -379,6 +350,33 @@ func (v *Visitor) Builtin(ctx *parser.GateCallStatementContext) (matrix.Matrix,
 	}
 }
 
+func (v *Visitor) Modify(u matrix.Matrix, n int, qargs [][]q.Qubit, modifier []parser.IGateModifierContext) (matrix.Matrix, error) {
+	for i, mod := range modifier {
+		switch {
+		case mod.CTRL() != nil:
+			u = Controlled(u, q.Index(qargs[i]...))
+		case mod.NEGCTRL() != nil:
+			u = NegControlled(u, n, q.Index(qargs[i]...))
+		case mod.INV() != nil:
+			u = u.Dagger()
+		case mod.POW() != nil:
+			var p float64
+			switch n := v.Visit(mod).(type) {
+			case float64:
+				p = n
+			case int64:
+				p = float64(n)
+			default:
+				return nil, fmt.Errorf("pow=%v: %w", n, ErrUnexpected)
+			}
+
+			u = Pow(u, p)
+		}
+	}
+
+	return u, nil
+}
+
 func (v *Visitor) Defined(ctx *parser.GateCallStatementContext) (matrix.Matrix, error) {
 	id := v.Visit(ctx.Identifier()).(string)
 	g, ok := v.Environ.GetGate(id)
@@ -439,7 +437,8 @@ func (v *Visitor) Defined(ctx *parser.GateCallStatementContext) (matrix.Matrix,
 	u := matrix.Apply(list...)
 
 	// modify
-	u, err := v.Modify(u, qargs, ctx.AllGateModifier())
+	n := v.qsim.NumberOfBit()
+	u, err := v.Modify(u, n, qargs, ctx.AllGateModifier())
 	if err != nil {
 		return nil, fmt.Errorf("modify: %w", err)
 	}