Coto - Abstract Additive Quantum Decision Diagrams

Theoretical research, experiments and implementation of abstract additive quantum decision diagrams, as part of a student research project.

Scientific manuscript and artifacts

The author-facing ACM manuscript, reproducibility commands, and known-limitations report are in paper/. Checked-in raw benchmark/fidelity data and paper figures are under analysis/results/; the longer-form theoretical notes remain in doc/.

Building

To build the project, you must have Clang, CMake and Ninja installed. The code uses some C++23 features, so a recent version of clang++ is required. Other versions probably work, but I personally use the following on my machine:

• Clang 19.1.7
• CMake 3.31.6
• Ninja 1.12.1

1. Configure the project

   git submodule update --init --recursive
   export CXX=$(which clang++)
   cmake -S . -B build -GNinja

2. Build the project

   cmake --build build

3. To run the tests (optional)

   cd build
   ctest

QASM interactive interpreter

After building the project (steps 1. and 2. above), simply run ./build/prompt. You can then enter QASM instructions, for example

qubit a;
qubit b;
h a;
p(pi/3) b;
cx a b;
h b;

This prompt utility comes with a few available run statements that should be ;-terminated:

• @build, @inst, @instantiate - create a new diagram
• @list, @actions - list the actions (gate applicaitons) to be performed
• @display, @evaluate, @eval - display the evaluation of the current diagram
• @intervals - emit machine-readable certified interval amplitudes (limited to 16 qubits)
• @describe, @desc - display the description of the current diagram
• @memory, @mem - display the memory usage of the current diagram
• @reduce(N) - enable approximate simulation and cap each nonterminal level at N nodes after every gate
• @exact - disable automatic reduction (the default)
• @help, @man, @manual - display a help message

Applying gates to qubits is deferred until a statement needs the diagram. @display, @describe, and @memory all simulate every queued gate first.

The prompt executable can also take a .qasm file path as an argument, in this case it quits after executing all statements in the file, without entering interactive mode.

Repository architecture

Presentation of this repository's main directories:

• .github/workflows GitHub actions continuous integration (CI) and continous deployment (CD) configuration files
  • Runs the unit tests that are in the test directory and marked as ready for testing in CMakeLists.txt
  • Generate the docs using Doxygen and publish them to maloleroy.github.io/coto using GitHub Pages
• archives Legacy documents or code, that still should be indexed
• doc Theory documents (basically, LaTeX)
• include Code header files (.h C++ files)
• ref References, code or case studies that can be used as examples
• s6 Final report and presentation for semester 6 (in French)
• s7 Final report and presentation for semester 6 (in French)
• src Source code (.cpp C++ files, not headers)
• test Test code (.cpp C++ files)