How to set-up a distributed computer cluster on your home network and use it to calculate a large correlation matrix.

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Calculating a correlation matrix can very quickly consume a vast amount of computational resources. Fortunately, correlation (and covariance) calculations can be intelligently split into multiple processes and distributed across a number of computers.

In this article, we will use Dask for Python to manage the parallel computation of a large correlation matrix across a number of computers on a Local Area Network.

What is a Correlation Matrix

If…


Part I — How to retrieve the stock holdings of Hedge Funds automatically using Python and store these in an SQL database.

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Introduction

Unfortunately for most investors, simply mimicking the investments you see in a 13F is unlikely to yield you much better than…


Send timely alerts to users even when your app isn’t running. In this example, we will send a daily notification showing the most-read story of the day on the Novella app using Firebase Cloud Messaging.

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We are going to be using the Firebase SDK for PHP which you can download here: https://github.com/kreait/firebase-php/. The first step will be to install this using Composer.

Installing Firebase SDK

The easiest way to install the Firebase SDK on your server is using Composer. …


Automatically saving content as it’s written is an essential part of the user experience. It’s used everywhere from Medium to Microsoft Word. Here’s how to implement this in Kotlin for Android.

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The Plan

To do this we need three things. Firstly, a user content form. Secondly, a way of determining when the user is typing and thirdly a way of…


Build a responsive UI that shows or hides the toolbar in response to user clicks whilst allowing undisturbed user scrolling.

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Kotlin has a fantastic ability to detect user gestures on Android systems. This is important for creating smooth, functional user interfaces that respond in a consistent and intuitive way. However, it can sometimes be difficult to differentiate between similar user actions. For example, when a user scrolls down a window of text this is detected as both a click and a scroll activity. …

Matthew Grint

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