Introduction

Hi, these are my solutions to the QHack 2021 quantum machine learning hackathon.
Everything is coded in Xanadu's PennyLane quantum programming package.
The original repo with all the hackathon details can be found at /XanaduAI/QHack2021.

Hackathon Details

Site: QHack.ai
Date: February 2021

Score

Here is a screenshot of my completed hackathon scoreboard entry.
I ranked 51^st in terms of cumulative completion time for the problem sets.

Files

The QML_Challenges folder contains all the problem statements and solutions.
Each problem set is in its own sub-folder with the name <topic>_<score>_template.
In each problem set, there is a .pdf problem statement and a .py solution.
There are also given test input .in and answers .ans with can be invoked in terminal via

>> python <problem name>_template.py < 1.in  

Topics

1. PennyLane Language
   • simple_circuits_20 - 1-qubit Circuits
   • simple_circuits_30 - 1-qubit Circuits
   • simple_circuits_50 - 2-qubit Circuits
2. Quantum Gradient (of Variational Parameters)
   • quantum_gradients_100 - Parameter-shift Rule
   • quantum_gradients_200 - Hessian Matrix
   • quantum_gradients_500 - Natural Gradient
3. Training/Optimisation (of Variational Circuits)
   • circuit_training_100 - PennyLane's Optimisers
   • circuit_training_200 - Maximal Independent Set
   • circuit_training_500 - Variational Classifier
4. Variational Quantum Eigensolver
   • vqe_100 - Variational Quantum Eigensolver (VQE)
   • vqe_200 - Ansatz Design
   • vqe_500 - VQE for Excited States