QuantumOptics.jl Development Guide

Expert guide for developing and contributing to QuantumOptics.jl, a numerical framework for simulating quantum systems including time evolution, master equations, stochastic processes, and more.

Project Overview

QuantumOptics.jl is built on QuantumOpticsBase.jl and provides dynamic solvers for closed and open quantum systems. It supports GPU acceleration (CUDA, AMDGPU, OpenCL) and automatic differentiation.

When to Use This Skill

Instructions

1. Environment Setup

**First, check if you're in the correct directory:**

**Install dependencies:**

```bash

julia --project=. -e "using Pkg; Pkg.instantiate()"

```

**Verify installation:**

```bash

julia --project=. -e "using Pkg; Pkg.status()"

```

2. Running Tests

**Run full test suite:**

```bash

julia --project=. -e "using Pkg; Pkg.test()"

```

**Run specific test categories:**

```bash

Schrödinger equation tests

julia --project=. -e "using TestItemRunner; @run_package_tests filter=ti->contains(string(ti.name), \"schroedinger\")"

Master equation tests

julia --project=. -e "using TestItemRunner; @run_package_tests filter=ti->contains(string(ti.name), \"master\")"

GPU tests (set appropriate environment variable)

CUDA_TEST=true julia --project=. -e "using Pkg; Pkg.test()"

AMDGPU_TEST=true julia --project=. -e "using Pkg; Pkg.test()"

Code quality tests

JET_TEST=true julia --project=. -e "using Pkg; Pkg.test()"

```

**Always run full test suite before creating/updating PRs.**

3. Code Structure Navigation

**Key source files:**

**Test files mirror source structure in `test/` directory.**

4. Code Formatting

**Before committing, format code:**

```bash

Remove trailing whitespaces

find . -type f -name '*.jl' -exec sed --in-place 's/[[:space:]]\+$//' {} \+

Ensure files end with newline

find . -type f -name '*.jl' -exec sed -i '$a\' {} \+

```

**Formatting guidelines:**

5. Git Workflow

**Always follow this workflow:**

1. **Pull latest changes first:**

```bash

git pull origin master

```

2. **Create feature branch:**

```bash

git checkout -b feature/your-feature-name

```

3. **Before continuing work on existing branch:**

```bash

git pull origin feature/your-feature-name

```

4. **Make changes and commit:**

```bash

git add <files>

git commit -m "Description of changes"

```

5. **Push to remote:**

```bash

git push origin feature/your-feature-name

```

6. **Run full test suite before PR:**

```bash

julia --project=. -e "using Pkg; Pkg.test()"

```

6. Development Best Practices

**Contributing guidelines:**

**Testing considerations:**

7. Package Management

**Update dependencies:**

```bash

julia --project=. -e "using Pkg; Pkg.update()"

```

**Run benchmarks:**

```bash

julia --project=benchmark benchmark/benchmarks.jl

```

Important Notes

Constraints

Example Usage

```bash

Setup new development environment

cd QuantumOptics.jl

julia --project=. -e "using Pkg; Pkg.instantiate()"

Create feature branch

git pull origin master

git checkout -b feature/improve-master-solver

Make changes to src/master.jl

Write tests in test/test_master.jl

Format code

find . -type f -name '*.jl' -exec sed --in-place 's/[[:space:]]\+$//' {} \+

Run tests

julia --project=. -e "using Pkg; Pkg.test()"

Commit and push

git add src/master.jl test/test_master.jl

git commit -m "Improve master equation solver performance"

git push origin feature/improve-master-solver

```