This is the open-source repository for the book Quantum Computing for Programmers by Robert Hundt, Cambridge University Press (QCC4CP for short). The book describes this implementation in great detail, including all the underlying math and derivations. Note, however, that this code base is evolving - not all algorithms found here are discussed in the book.
To get started quickly on the Python sources, you may find the Quickstart Guide helpful.
This project builds vendor-independent infrastructure from the ground up and implements standard algorithms, such as Quantum Teleportation, Superdense coding, Deutsch-Jozsa, Bernstein-Vazirani, Quantum Phase estimation (QPE), Grover's Search (with application to Quantum counting, amplitude estimation, Mean and Median estimation, 3SAT, Graph Coloring, and Minimum finding), Quantum random walks, VQE, Max-Cut, Subset-Sum, Quantum Fourier Transform (QFT), Shor's integer factorization, Solovay-Kitaev, Principal Component Analysis, and a few more. It also implements high performance quantum simulation and a transpilation technique to compile circuits to other infrastructures, such as Qiskit or Cirq.
The code is organized as follows:
src is the main source directory. All algorithms are in this directory.src/lib contains the library functions for tensors, states, operators, circuits, and so on, as well as their corresponding tests. All algorithms depend on these library functions.src/libq contains the sparse implementation.src/benchmarks contains a few benchmarks, as they are mentioned in the book.resources contains additional text, sections and chapters.errata contains the errata for the book - corrections and clarifications.external contains the *.BUILD files to point bazel to python and numpy.There are several ways to get started on this code base:
The main algorithms are all in src.
To run individual algorithms via bazel, run any of these command lines. Note the missing .py extensions when using bazel). Alternatively, run each Python file with python <file> (PYTHONPATH must point to the root directory):
# Algorithms discussed in the book:
bazel run arith_classic
bazel run arith_quantum
bazel run bernstein
bazel run counting
bazel run deutsch
bazel run deutsch_jozsa
bazel run entanglement_swap
bazel run grover
bazel run max_cut
bazel run order_finding
bazel run phase_estimation
bazel run phase_kick
bazel run quantum_walk
bazel run shor_classic
bazel run simon
bazel run simon_general
bazel run solovay_kitaev
bazel run subset_sum
bazel run superdense
bazel run supremacy
bazel run swap_test
bazel run teleportation
bazel run vqe_simple
# Additional algorithms and techniques, to clarify, or
# in preparation of a new edition of the book:
bazel run amplitude_estimation
bazel run bell_basis
bazel run chsh
bazel run estimate_pi
bazel run euclidean_distance
bazel run graph_coloring
bazel run hadamard_test
bazel run hamiltonian_encoding
bazel run hhl
bazel run hhl_2x2
bazel run inversion_test
bazel run minimum_finding
bazel run oracle_synth
bazel run pauli_rep
bazel run purification
bazel run qram
bazel run quantum_mean
bazel run quantum_median
bazel run quantum_pca
bazel run sat3
bazel run schmidt_decomp
bazel run spectral_decomp
bazel run state_prep
bazel run state_prep_mottonen
bazel run zy_decomp
To test aspects of the sparse implementation:
cd src/libq
bazel test ...To run the benchmarks:
cd src/benchmarks
bazel run larose_benchmark
bazel run tensor_mathTo experiment with transpilation, a few things must work together:
Specify a target output. For example, to generate a libq C++ file, use --libq=./test.cc
The code should only contain a single circuit.qc()-generated circuit. This circuit will not
be eagerly executed. Instead, all gates and qubits will be collected in an internal IR.
There must be a single call to qc.dump_to_file(). The circuit as that point
will be transpiled to the target platform (an example of this can be found in
order_finding.py).
For the given example, the generated file test.cc can be compiled and linked with libq
with a command-line similar to this one:
$ cd qcc/src
$ cc -O2 -Ilibq test.cc libq/qureg.cc libq/apply.cc libq/gates.cc -o a.out -lc++
$ a.outThis code and book were written by Robert Hundt. At the time of this writing, Robert is a Distinguished Enginer at Google. However, this is a private project, developed on personal infrastructure and in private time. It is completely independent of Robert's work at Google.
Reach Robert at