The quantum Fourier transform is a key building block of many quantum algorithms, from Shor's factoring algorithm over matrix inversion to quantum phase estimation and simulations. Time to see how this can be implemented with Qiskit. Recall that the quantum Fourier transform (or, depending on conventions, its inverse) is given by $latex |x \rangle \mapsto … Continue reading Implementing the quantum Fourier transform with Qiskit

# Category: Python

# Running the Deutsch-Jozsa algorithm on IBMs Q experience

In one of the previous posts, we have looked at the basics of the Qiskit package that allows us to create and run quantum algorithms in Python. In this post, we will apply this to model and execute a real quantum algorithm - the Deutsch-Jozsa algorithm. Recall that the Deutsch-Jozsa algorithm is designed to solve … Continue reading Running the Deutsch-Jozsa algorithm on IBMs Q experience

# Using Python to access IBMs quantum computers

In a previous post, we have looked at IBMs Q experience and the graphical composer that you can use to build simple circuits and run them on the IBM hardware. Alternatively, the quantum hardware can be addressed using an API and a Python library called Qiskit which we investigate in this post. Installation and setup … Continue reading Using Python to access IBMs quantum computers

# Shor’s quantum factoring algorithm

Until the nineties of the last century, quantum computing seemed to be an interesting theoretical possibility, but it was far from clear whether it could be useful to tackle computationally hard problems with high relevance for actual complications. This changed dramatically in 1994, when the mathematician P. Shor announced a quantum algorithm that could efficiently … Continue reading Shor’s quantum factoring algorithm

# More on Paperspace Gradient

Its been a few days since I started to play with Paperspace, and I have come across a couple of interesting features that the platform has - enough for a second post on this topic. First, GIT integration. Recall that the usual process is to zip the current working directory and submit the resulting file … Continue reading More on Paperspace Gradient

# First steps with Paperspace Gradient

So far, I have exclusively been using AWS EC2 when I needed access to a GPU - not because I have carefully compared the available offerings and taken a deliberate decision, but simply because I already had an EC2 account and know the platform. However, I though it would be interesting to try out other … Continue reading First steps with Paperspace Gradient

# The EM algorithm and Gaussian mixture models – part II

In this post, I will discuss the general form of the EM algorithm to obtain a maximum likelihood estimator for a model with latent variables. First, let us describe our model. We suppose that we are given some joint distribution of a random variable X (the observed variables) and and random variable Z (the latent … Continue reading The EM algorithm and Gaussian mixture models – part II