Merge branch 'develop' into feature/openqasm

.github/workflows/publish_release.yml

@@ -1,6 +1,7 @@
 name: "Publish new release"
 
 on:
+  workflow_dispatch:
   push:
     tags:
       - v[0-9]+.*
@@ -14,78 +15,59 @@ jobs:
   packaging:
     name: Build wheels on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
-    if: startsWith(github.ref, 'refs/tags/') || (github.event_name == 'pull_request' && github.event.pull_request.merged == true)
+    if: startsWith(github.ref, 'refs/tags/') || (github.event_name == 'pull_request' && github.event.pull_request.merged == true) || github.event_name == 'workflow_dispatch'
     strategy:
       matrix:
-        os: [ubuntu-20.04, windows-2019, macos-10.15]
+        os:
+          - ubuntu-latest
 
     steps:
       - uses: actions/checkout@v2
+        if: github.event_name != 'workflow_dispatch'
+
+      - uses: actions/checkout@v2
+        if: github.event_name == 'workflow_dispatch'
+        with:
+          ref: 'master'
 
       - name: Get history and tags for SCM versioning to work
         run: |
           git fetch --prune --unshallow
           git fetch --depth=1 origin +refs/tags/*:refs/tags/*
 
-      - name: Extract version from tag name (Unix)
-        if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/') && runner.os != 'Windows'
-        run: |
-          TAG_NAME="${GITHUB_REF/refs\/tags\//}"
-          VERSION=${TAG_NAME#v}
-
-          echo "RELEASE_VERSION=$VERSION" >> $GITHUB_ENV
+      # ========================================================================
 
       - name: Extract version from branch name (for release branches) (Unix)
         if:  github.event_name == 'pull_request' && startsWith(github.event.pull_request.head.ref, 'release/') && runner.os != 'Windows'
         run: |
           BRANCH_NAME="${{ github.event.pull_request.head.ref }}"
           VERSION=${BRANCH_NAME#release/}
-
-          echo "RELEASE_VERSION=$VERSION" >> $GITHUB_ENV
-          git tag v${RELEASE_VERSION} master
+          git tag v${VERSION} master
 
       - name: Extract version from branch name (for hotfix branches) (Unix)
         if: github.event_name == 'pull_request'  && startsWith(github.event.pull_request.head.ref, 'hotfix/') && runner.os != 'Windows'
         run: |
           BRANCH_NAME="${{ github.event.pull_request.head.ref }}"
           VERSION=${BRANCH_NAME#hotfix/}
+          git tag v${VERSION} master
 
-          echo "RELEASE_VERSION=$VERSION" >> $GITHUB_ENV
-          git tag v${RELEASE_VERSION} master
-
-
-      - name: Extract version from tag name (Windows)
-        if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/') && runner.os == 'Windows'
-        run: |
-          $TAG_NAME = $GITHUB_REF -replace "refs/tags/",""
-          $VERSION = $TAG_NAME -replace "v",""
-
-          Write-Output "RELEASE_VERSION=$VERSION" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+      # ------------------------------------------------------------------------
 
       - name: Extract version from branch name (for release branches) (Windows)
         if:  github.event_name == 'pull_request' && startsWith(github.event.pull_request.head.ref, 'release/') && runner.os == 'Windows'
         run: |
           $BRANCH_NAME="${{ github.event.pull_request.head.ref }}"
           $VERSION = $BRANCH_NAME -replace "release/",""
+          git tag v${VERSION} master
 
-          Write-Output "RELEASE_VERSION=$VERSION" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
-          git tag v${RELEASE_VERSION} master
-
-      - name: Extract version from branch name (for hotfix branches) (Unix)
+      - name: Extract version from branch name (for hotfix branches) (Windows)
         if: github.event_name == 'pull_request'  && startsWith(github.event.pull_request.head.ref, 'hotfix/') && runner.os == 'Windows'
         run: |
           $BRANCH_NAME="${{ github.event.pull_request.head.ref }}"
           $VERSION = $BRANCH_NAME -replace "hotfix/",""
+          git tag v${VERSION} master
 
-          Write-Output "RELEASE_VERSION=$VERSION" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
-          git tag v${RELEASE_VERSION} master
-
-      - name: Build wheels
-        uses: joerick/[email protected]
-        env:
-          CIBW_ARCHS: auto64
-          CIBW_SKIP: cp27-* pp* cp35-*
-          CIBW_BEFORE_BUILD: python -m pip install pybind11
+      # ========================================================================
 
       - name: Build source distribution
         if: runner.os == 'Linux'
@@ -101,11 +83,21 @@ jobs:
           name: packages
           path: ./wheelhouse/*
 
+
   release:
     name: Publish new release
     runs-on: ubuntu-latest
-    needs: packaging
+    needs:
+      - packaging
     steps:
+      - name: Extract version from tag name (workflow_dispatch)
+        if: github.event_name == 'workflow_dispatch'
+        run: |
+          TAG_NAME=$(git describe --tags `git rev-list --tags --max-count=1`)
+          VERSION=${TAG_NAME#v}
+
+          echo "RELEASE_VERSION=$VERSION" >> $GITHUB_ENV
+
       - name: Extract version from tag name
         if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/')
         run: |
@@ -130,8 +122,18 @@ jobs:
 
           echo "RELEASE_VERSION=$VERSION" >> $GITHUB_ENV
 
+      # ------------------------------------------------------------------------
+      # Checkout repository to get CHANGELOG
+
       - uses: actions/checkout@v2
+        if: github.event_name != 'workflow_dispatch'
+
+      - uses: actions/checkout@v2
+        if: github.event_name == 'workflow_dispatch'
+        with:
+          ref: 'master'
 
+      # ------------------------------------------------------------------------
       # Downloads all to directories matching the artifact names
       - uses: actions/download-artifact@v2
 
@@ -164,7 +166,7 @@ jobs:
   upload_to_pypi:
     name: Upload to PyPI
     runs-on: ubuntu-latest
-    needs: release # Only upload to PyPi if everything was successful
+    needs: release
     steps:
     - uses: actions/setup-python@v2
 
@@ -181,7 +183,9 @@ jobs:
   master_to_develop_pr:
     name: Merge master back into develop
     runs-on: ubuntu-latest
-    needs: release # Only create PR if everything was successful
+    needs:
+      - release
+      - upload_to_pypi
     steps:
       - name: Merge master into develop branch
         uses: thomaseizinger/[email protected]

CHANGELOG.md

@@ -9,12 +9,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- UnitarySimulator backend for computing the unitary transformation corresponding to a quantum circuit.
 - Added OpenQASMBackend to output QASM from ProjectQ circuits
 
-
 ### Changed
 ### Deprecated
 ### Fixed
+
+-   Prevent infinite recursion errors when too many compiler engines are added to the MainEngine
+
 ### Removed
 ### Repository
 
@@ -24,6 +27,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 -   Fix GitHub workflow for publishing a new release
 
+
 ## [0.6.0] - 2021-06-23
 
 ### Added

examples/unitary_simulator.py

@@ -0,0 +1,82 @@
+# -*- coding: utf-8 -*-
+#   Copyright 2021 ProjectQ-Framework (www.projectq.ch)
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+# pylint: skip-file
+
+"""Example of using the UnitarySimulator."""
+
+
+import numpy as np
+
+from projectq.backends import UnitarySimulator
+from projectq.cengines import MainEngine
+from projectq.meta import Control
+from projectq.ops import All, X, QFT, Measure, CtrlAll
+
+
+def run_circuit(eng, n_qubits, circuit_num, gate_after_measure=False):
+    """Run a quantum circuit demonstrating the capabilities of the UnitarySimulator."""
+    qureg = eng.allocate_qureg(n_qubits)
+
+    if circuit_num == 1:
+        All(X) | qureg
+    elif circuit_num == 2:
+        X | qureg[0]
+        with Control(eng, qureg[:2]):
+            All(X) | qureg[2:]
+    elif circuit_num == 3:
+        with Control(eng, qureg[:2], ctrl_state=CtrlAll.Zero):
+            All(X) | qureg[2:]
+    elif circuit_num == 4:
+        QFT | qureg
+
+    eng.flush()
+    All(Measure) | qureg
+
+    if gate_after_measure:
+        QFT | qureg
+    eng.flush()
+    All(Measure) | qureg
+
+
+def main():
+    """Definition of the main function of this example."""
+    # Create a MainEngine with a unitary simulator backend
+    eng = MainEngine(backend=UnitarySimulator())
+
+    n_qubits = 3
+
+    # Run out quantum circuit
+    #   1 - circuit applying X on all qubits
+    #   2 - circuit applying an X gate followed by a controlled-X gate
+    #   3 - circuit applying a off-controlled-X gate
+    #   4 - circuit applying a QFT on all qubits (QFT will get decomposed)
+    run_circuit(eng, n_qubits, 3, gate_after_measure=True)
+
+    # Output the unitary transformation of the circuit
+    print('The unitary of the circuit is:')
+    print(eng.backend.unitary)
+
+    # Output the final state of the qubits (assuming they all start in state |0>)
+    print('The final state of the qubits is:')
+    print(eng.backend.unitary @ np.array([1] + ([0] * (2 ** n_qubits - 1))))
+    print('\n')
+
+    # Show the unitaries separated by measurement:
+    for history in eng.backend.history:
+        print('Previous unitary is: \n', history, '\n')
+
+
+if __name__ == '__main__':
+    main()

projectq/backends/__init__.py

@@ -36,3 +36,4 @@
 from ._aqt import AQTBackend
 from ._awsbraket import AWSBraketBackend
 from ._ionq import IonQBackend
+from ._unitary import UnitarySimulator