Python（Cirq）について（１５）

概要

Cirq について, Optimizers, Decompositions に関するサンプルをいくつか動かしてみた.
動作環境は, Google Colaboratory で行った

感想

量子物理学に関する知識(用語, 数式の意味ほか)は, 徐々に身につけていく必要があると感じた.
時間を見つけて, 今後も, ドキュメントの残りの部分を進めていこうと思う.

Circuit optimizers

Momentの個数を削減することが出来る場合があるとのこと

Circuit optimizers を使うサンプル

[編集内容(Circuit optimizers)]
import cirq

# Moment の 個数 を 削減できるケース.
c = cirq.Circuit()
c.append(cirq.Moment([]))
c.append(cirq.Moment([cirq.X(cirq.GridQubit(1, 1))]))
c.append(cirq.Moment([]))
print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)
print(f'After optimization, Circuit has {len(c)} moments')

[編集内容(Circuit optimizers)]

import cirq

# Moment の個数を削減できるケース.

c = cirq.Circuit()

c.append(cirq.Moment([]))

c.append(cirq.Moment([cirq.X(cirq.GridQubit(1, 1))]))

c.append(cirq.Moment([]))

print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)

print(f'After optimization, Circuit has {len(c)} moments')

[出力結果]
Before optimization, Circuit has 3 moments
After optimization, Circuit has 1 moments

[出力結果]

Before optimization, Circuit has 3 moments

After optimization, Circuit has 1 moments

Circuit optimizers を使うサンプル

[編集内容(Circuit optimizers)]
import cirq

# Moment の 個数 を 削減できないケース.
c = cirq.Circuit()

q0, q1 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)

c.append(cirq.Moment(cirq.SWAP(q0, q1)))
c.append(cirq.Moment(cirq.SWAP(q0, q1)))
c.append(cirq.Moment(cirq.SWAP(q0, q1)))
print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)
print(f'After optimization, Circuit has {len(c)} moments')

[編集内容(Circuit optimizers)]

import cirq

# Moment の個数を削減できないケース.

c = cirq.Circuit()

q0, q1 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)

c.append(cirq.Moment(cirq.SWAP(q0, q1)))

print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)

print(f'After optimization, Circuit has {len(c)} moments')

[出力結果]
Before optimization, Circuit has 3 moments
After optimization, Circuit has 3 moments

[出力結果]

Before optimization, Circuit has 3 moments

After optimization, Circuit has 3 moments

Circuit optimizers を使うサンプル

[編集内容(Circuit optimizers)]
import cirq

# Moment の 個数 を 削減できるケース.
c = cirq.Circuit()

c.append(cirq.SWAP(q, q + 1) for q in cirq.LineQubit.range(3))
c.append([cirq.Moment()])
c.append([cirq.Moment()])
print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)
print(f'After optimization, Circuit has {len(c)} moments')

[編集内容(Circuit optimizers)]

import cirq

# Moment の個数を削減できるケース.

c = cirq.Circuit()

c.append(cirq.SWAP(q, q + 1) for q in cirq.LineQubit.range(3))

c.append([cirq.Moment()])

print(f'Before optimization, Circuit has {len(c)} moments')

cirq.DropEmptyMoments().optimize_circuit(circuit=c)

print(f'After optimization, Circuit has {len(c)} moments')

[出力結果]
Before optimization, Circuit has 5 moments
After optimization, Circuit has 3 moments

[出力結果]

Before optimization, Circuit has 5 moments

After optimization, Circuit has 3 moments

Decompositions

量子回路を変形することができる

Decompositions を使うサンプル

[編集内容(Decompositions)]
import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0 = cirq.GridQubit(0, 0)

c1.append(cirq.H(q0))
print('Before Decompositions:\n', c1)

c2.append(cirq.H(q0))
print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[編集内容(Decompositions)]

import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0 = cirq.GridQubit(0, 0)

c1.append(cirq.H(q0))

print('Before Decompositions:\n', c1)

c2.append(cirq.H(q0))

print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[出力結果]
Before Decompositions:
 (0, 0): ───H───
After Decompositions:
 (0, 0): ───Y^0.5───X───

[出力結果]

Before Decompositions:

(0, 0): ───H───

After Decompositions:

(0, 0): ───Y^0.5───X───

Decompositions を使うサンプル

[編集内容(Decompositions)]
import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0, q1 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)

c1.append(cirq.X(q0))
c1.append(cirq.CNOT(q0, q1))
print('Before Decompositions:\n', c1)

c2.append(cirq.X(q0))
c2.append(cirq.CNOT(q0, q1))
print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[編集内容(Decompositions)]

import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0, q1 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)

c1.append(cirq.X(q0))

c1.append(cirq.CNOT(q0, q1))

print('Before Decompositions:\n', c1)

c2.append(cirq.X(q0))

c2.append(cirq.CNOT(q0, q1))

print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[出力結果]
Before Decompositions:
 (0, 0): ───X───@───
               │
(0, 1): ───────X───
After Decompositions:
 (0, 0): ───X────────@───────────
                    │
(0, 1): ───Y^-0.5───@───Y^0.5───

[出力結果]

Before Decompositions:

(0, 0): ───X───@───

│

(0, 1): ───────X───

After Decompositions:

(0, 0): ───X────────@───────────

│

(0, 1): ───Y^-0.5───@───Y^0.5───

Decompositions を使うサンプル

[編集内容(Decompositions)]
import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0, q1, q2 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1), cirq.GridQubit(0, 2)

c1.append(cirq.X(q0))
c1.append(cirq.X(q1))
c1.append(cirq.CCNOT(q0, q1, q2))
print('Before Decompositions:\n', c1)

c2.append(cirq.X(q0))
c2.append(cirq.X(q1))
c2.append(cirq.CCNOT(q0, q1, q2))
print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[編集内容(Decompositions)]

import cirq

c1, c2 = cirq.Circuit(), cirq.Circuit()

q0, q1, q2 = cirq.GridQubit(0, 0), cirq.GridQubit(0, 1), cirq.GridQubit(0, 2)

c1.append(cirq.X(q0))

c1.append(cirq.X(q1))

c1.append(cirq.CCNOT(q0, q1, q2))

print('Before Decompositions:\n', c1)

c2.append(cirq.X(q0))

c2.append(cirq.X(q1))

c2.append(cirq.CCNOT(q0, q1, q2))

print('After Decompositions:\n', cirq.Circuit(cirq.decompose(c2)))

[出力結果]
Before Decompositions:
 (0, 0): ───X───@───
               │
(0, 1): ───X───@───
               │
(0, 2): ───────X───
After Decompositions:
 (0, 0): ───X───────T────────────@─────────────────────────────────────@─────────────────────────────@────────────────────────────@───────────────────────────────────────
                                │                                     │                             │                            │
(0, 1): ───X───────T───Y^-0.5───@────────Y^0.5───@───T^-1────Y^-0.5───@────────Y^0.5───@───Y^-0.5───@──────Y^0.5────@───Y^-0.5───@──────Y^0.5────@───────────────────────
                                                 │                                     │                            │                            │
(0, 2): ───Y^0.5───X───T────────Y^-0.5───────────@───Y^0.5───T────────Y^-0.5───────────@───Y^0.5────T^-1───Y^-0.5───@───Y^0.5────T^-1───Y^-0.5───@───Y^0.5───Y^0.5───X───

[出力結果]

Before Decompositions:

(0, 0): ───X───@───

│

(0, 1): ───X───@───

│

(0, 2): ───────X───

After Decompositions:

(0, 0): ───X───────T────────────@─────────────────────────────────────@─────────────────────────────@────────────────────────────@───────────────────────────────────────

│ │ │ │

(0, 1): ───X───────T───Y^-0.5───@────────Y^0.5───@───T^-1────Y^-0.5───@────────Y^0.5───@───Y^-0.5───@──────Y^0.5────@───Y^-0.5───@──────Y^0.5────@───────────────────────

│ │ │ │

(0, 2): ───Y^0.5───X───T────────Y^-0.5───────────@───Y^0.5───T────────Y^-0.5───────────@───Y^0.5────T^-1───Y^-0.5───@───Y^0.5────T^-1───Y^-0.5───@───Y^0.5───Y^0.5───X───

Create your own optimizers

例えば, 測定を後から外すことも出来るとのこと

Create your own optimizers を使うサンプル

[編集内容(Create your own optimizers)]
import cirq

class RemoveMeasurements(cirq.PointOptimizer):
    def optimization_at(self, circuit: cirq.Circuit, index: int, op: cirq.Operation):
      if isinstance(op.gate, cirq.MeasurementGate):
        return cirq.PointOptimizationSummary(clear_span=1,
                                             new_operations=[],
                                             clear_qubits=op.qubits)
      else:
        return None

q0, q1, q2 = cirq.LineQubit(0), cirq.LineQubit(1), cirq.LineQubit(2)
c = cirq.Circuit()
c.append(cirq.X(q0))
c.append(cirq.X(q1))
c.append(cirq.CCNOT(q0, q1, q2))
c.append(cirq.CSWAP(q1, q2, q0))
c.append(cirq.measure(q0, key='result 0'))
c.append(cirq.measure(q1, key='result 1'))
c.append(cirq.measure(q2, key='result 2'))
print('Before optimization')
print(c)
RemoveMeasurements().optimize_circuit(c)
print('After optimization')
print(c)

[編集内容(Create your own optimizers)]

import cirq

class RemoveMeasurements(cirq.PointOptimizer):

def optimization_at(self, circuit: cirq.Circuit, index: int, op: cirq.Operation):

if isinstance(op.gate, cirq.MeasurementGate):

return cirq.PointOptimizationSummary(clear_span=1,

new_operations=[],

clear_qubits=op.qubits)

else:

return None

q0, q1, q2 = cirq.LineQubit(0), cirq.LineQubit(1), cirq.LineQubit(2)

c = cirq.Circuit()

c.append(cirq.X(q0))

c.append(cirq.X(q1))

c.append(cirq.CCNOT(q0, q1, q2))

c.append(cirq.CSWAP(q1, q2, q0))

c.append(cirq.measure(q0, key='result 0'))

c.append(cirq.measure(q1, key='result 1'))

c.append(cirq.measure(q2, key='result 2'))

print('Before optimization')

print(c)

RemoveMeasurements().optimize_circuit(c)

print('After optimization')

print(c)

[出力結果]
Before optimization
0: ───X───@───×───M('result 0')───
          │   │
1: ───X───@───@───M('result 1')───
          │   │
2: ───────X───×───M('result 2')───
After optimization
0: ───X───@───×───────
          │   │
1: ───X───@───@───────
          │   │
2: ───────X───×───────

[出力結果]

Before optimization

0: ───X───@───×───M('result 0')───

│ │

1: ───X───@───@───M('result 1')───

│ │

2: ───────X───×───M('result 2')───

After optimization

0: ───X───@───×───────

│ │

1: ───X───@───@───────

│ │

2: ───────X───×───────

Python（Cirq）について（１５）

概要

感想

Circuit optimizers

Decompositions

Create your own optimizers

参照サイト

コメントを残すコメントをキャンセル

概要

感想

Circuit optimizers

Decompositions

Create your own optimizers

参照サイト

コメントを残す コメントをキャンセル

コメントを残すコメントをキャンセル