CircuitSimulator

To build the simulator execute, build the ddsim_simple (the name stuck due to historical reasons ;) ) CMake target and run the resulting executable with options according to your needs.

The standalone executable is launched in the following way, showing available options:

$ ./ddsim_simple --help
MQT DDSIM by https://www.cda.cit.tum.de/ -- Allowed options:
-h [ --help ]                         produce help message
--seed arg (=0)                       seed for random number generator (default zero is possibly directly used as seed!)
--shots arg (=0)                      number of measurements (if the algorithm does not contain non-unitary gates, weak simulation is used)
--pv                                  display the state vector as list of pairs (real and imaginary parts)
--ps                                  print simulation stats (applied gates, sim. time, and maximal size of the DD)
--pm                                  print measurement results
--pcomplex                            print print additional statistics on complex numbers
--verbose                             Causes some simulators to print additional information to STDERR
--simulate_file arg                   simulate a quantum circuit given by file (detection by the file extension)
--simulate_file_hybrid arg            simulate a quantum circuit given by file (detection by the file extension) using the hybrid Schrodinger-Feynman simulator
--hybrid_mode arg                     mode used for hybrid Schrodinger-Feynman simulation (*amplitude*, dd)
--nthreads arg (=2)                   #threads used for hybrid simulation
--simulate_qft arg                    simulate Quantum Fourier Transform for given number of qubits
--simulate_ghz arg                    simulate state preparation of GHZ state for given number of qubits
--step_fidelity arg (=1)              target fidelity for each approximation run (>=1 = disable approximation)
--steps arg (=1)                      number of approximation steps
--simulate_grover arg                 simulate Grover's search for given number of qubits with random oracle
--simulate_grover_emulated arg        simulate Grover's search for given number of qubits with random oracle and emulation
--simulate_grover_oracle_emulated arg simulate Grover's search for given number of qubits with given oracle and emulation
--simulate_shor arg                   simulate Shor's algorithm factoring this number
--simulate_shor_coprime arg (=0)      coprime number to use with Shor's algorithm (zero randomly generates a coprime)
--simulate_shor_no_emulation          Force Shor simulator to do modular exponentiation instead of using emulation (you'll usually want emulation)
--simulate_fast_shor arg              simulate Shor's algorithm factoring this number with intermediate measurements
--simulate_fast_shor_coprime arg (=0) coprime number to use with Shor's algorithm (zero randomly generates a coprime)

The output is JSON-formatted as shown below (with hopefully intuitive naming).

$ cmake -DCMAKE_BUILD_TYPE=Release -S . -B build
$ cmake --build build --config Release --target ddsim_simple
$ ./build/ddsim_simple --simulate_ghz 4 --shots 1000 --ps --pm
{
  "measurement_results": {
    "0000": 484,
    "1111": 516
  },
  "statistics": {
    "applied_gates": 4,
    "approximation_runs": "0",
    "benchmark": "entanglement_4",
    "distinct_results": 2,
    "final_fidelity": "1.000000",
    "max_nodes": 9,
    "n_qubits": 4,
    "seed": "0",
    "shots": 1000,
    "simulation_time": 0.00013726699398830533,
    "single_shots": "1",
    "step_fidelity": "1.000000"
  }
}

Quickstart Guide

Execute the following lines to get the simulator running in no time:

$ git clone --recurse-submodules https://github.com/cda-tum/ddsim/
[...]

$ cd ddsim

ddsim/ $ cmake -S . -B build
-- Build files have been written to: /.../build

ddsim/ $ cmake --build build --config Release --target ddsim_simple
[...]
[100%] Built target ddsim_simple

ddsim/ $ build/ddsim_simple --help
MQT DDSIM by https://www.cda.cit.tum.de/ -- Allowed options:
  -h [ --help ]                         produce help message
[...]

If you are using this simulator, please cite [Zulehner and Wille, 2019].