Data, solutions, and machines. https://lettier.github.io/rss.xml (C) 2017 David Lettier. All rights reserved. David Lettier Mon, 23 Oct 2017 00:00:00 EST Using PureScript, Pure11, C++, and SFML, we programmatically create a recursive animation. https://lettier.github.io/posts/2017-10-23-animation-purescript-cpp-sfml.html https://lettier.github.io/posts/2017-10-23-animation-purescript-cpp-sfml.html David Lettier Wed, 30 Aug 2017 00:00:00 EST Using Haskell, GTK+, GStreamer, xlib, and the haskell-gi bindings, we build a video player complete with seek and volume controls. https://lettier.github.io/posts/2017-08-30-haskell-gtk-video-player.html https://lettier.github.io/posts/2017-08-30-haskell-gtk-video-player.html David Lettier Sat, 25 Feb 2017 00:00:00 EST Using PureScript and the Halogen library, we build a matrix inverse calculator from the ground up. https://lettier.github.io/posts/2017-02-25-matrix-inverse-purescript.html https://lettier.github.io/posts/2017-02-25-matrix-inverse-purescript.html David Lettier Sun, 15 Jan 2017 00:00:00 EST Using PureScript, Halogen, and Chart.js, we implement linear regression, gradient descent, and the PRESS statistic from the ground up. https://lettier.github.io/posts/2017-01-15-linear-regression-and-the-amazing-beard.html https://lettier.github.io/posts/2017-01-15-linear-regression-and-the-amazing-beard.html David Lettier Tue, 25 Oct 2016 00:00:00 EST Using Vue.js, we build a JavaScript based search engine capable of using tf-idf VSM and Okapi BM25 simultaneously. https://lettier.github.io/posts/2016-10-25-tf-idf-vsm-vs-bm25-with-vuejs.html https://lettier.github.io/posts/2016-10-25-tf-idf-vsm-vs-bm25-with-vuejs.html David Lettier Mon, 10 Oct 2016 00:00:00 EST Using Haskell, R, Python, SQLite, and Elasticsearch, we data mine Hacker News front page stories and their back page counterparts for patterns. https://lettier.github.io/posts/2016-10-10-data-mining-hacker-news-front-vs-back.html https://lettier.github.io/posts/2016-10-10-data-mining-hacker-news-front-vs-back.html David Lettier Mon, 15 Aug 2016 00:00:00 EST Using Haskell's Blaze, Fay, and Clay, we build an Electron desktop video player application. https://lettier.github.io/posts/2016-08-15-making-movie-monad.html https://lettier.github.io/posts/2016-08-15-making-movie-monad.html David Lettier Fri, 05 Aug 2016 00:00:00 EST Using a fictitious scenario, we explore the Matthews Correlation Coefficient quality measure of binary classification. https://lettier.github.io/posts/2016-08-05-matthews-correlation-coefficient.html https://lettier.github.io/posts/2016-08-05-matthews-correlation-coefficient.html David Lettier Fri, 15 Jul 2016 00:00:00 EST Using the Snap framework, we build a web server API that creates, reads, updates, and deletes web bookmarks. https://lettier.github.io/posts/2016-07-15-building-a-haskell-web-api.html https://lettier.github.io/posts/2016-07-15-building-a-haskell-web-api.html David Lettier Mon, 04 Jul 2016 00:00:00 EST Using Reflex-FRP, we generate a stylized push button interface widget written in Haskell and playable in a web browser. https://lettier.github.io/posts/2016-07-04-haskell-to-javascript.html https://lettier.github.io/posts/2016-07-04-haskell-to-javascript.html David Lettier Fri, 10 Jun 2016 00:00:00 EST Using JavaScript, we implement the k-Nearest Neighbors algorithm from the bottom up. https://lettier.github.io/posts/2016-06-10-k-nearest-neighbors-from-scratch.html https://lettier.github.io/posts/2016-06-10-k-nearest-neighbors-from-scratch.html David Lettier Wed, 01 Jun 2016 00:00:00 EST Using Haskell, we collect, process, and plot NYC 311 complaints. https://lettier.github.io/posts/2016-06-01-data-visualization-with-haskell-nyc-public-urination.html https://lettier.github.io/posts/2016-06-01-data-visualization-with-haskell-nyc-public-urination.html David Lettier Thu, 12 May 2016 00:00:00 EST Using FuntionalJS, PhysicsJS, PubSubJS, and EaselJS, we develop a HTML5 canvas game called Dubul Rubul. https://lettier.github.io/posts/2016-05-12-make-a-html5-canvas-game-with-physics.html https://lettier.github.io/posts/2016-05-12-make-a-html5-canvas-game-with-physics.html David Lettier Fri, 29 Apr 2016 00:00:00 EST Using Haskell, we implement the breadth-first search algorithm. https://lettier.github.io/posts/2016-04-29-breadth-first-search-in-haskell.html https://lettier.github.io/posts/2016-04-29-breadth-first-search-in-haskell.html David Lettier Tue, 26 Apr 2016 00:00:00 EST Using C, we build a Network Time Protocol client capable of getting the current time from a remote NTP server. https://lettier.github.io/posts/2016-04-26-lets-make-a-ntp-client-in-c.html https://lettier.github.io/posts/2016-04-26-lets-make-a-ntp-client-in-c.html David Lettier Sun, 24 Apr 2016 00:00:00 EST Using vanilla JavaScript, we build an interactive k-means clustering application from scratch and test the clusters using the silhouette coefficient metric. https://lettier.github.io/posts/2016-04-24-k-means-from-scratch.html https://lettier.github.io/posts/2016-04-24-k-means-from-scratch.html David Lettier Fri, 22 Apr 2016 00:00:00 EST Using Haskell, we implement the Fibonacci sequence, Least Common Multiple (LCM), and the Greatest Common Divisor (GCD). https://lettier.github.io/posts/2016-04-22-fibonacci-lcm-and-gcd-in-haskell.html https://lettier.github.io/posts/2016-04-22-fibonacci-lcm-and-gcd-in-haskell.html David Lettier Thu, 14 Apr 2016 00:00:00 EST Using Haskell, we implement the linear time algorithm that solves the max subarray problem. https://lettier.github.io/posts/2016-04-14-max-subarray-in-haskell.html https://lettier.github.io/posts/2016-04-14-max-subarray-in-haskell.html David Lettier Sun, 10 Apr 2016 00:00:00 EST Using scikit-learn, we build a binary classifier model capable of classifying greeting cards as either birthday or condolences. https://lettier.github.io/posts/2016-04-10-birthday-condolences-greeting-card-classifier.html https://lettier.github.io/posts/2016-04-10-birthday-condolences-greeting-card-classifier.html David Lettier Mon, 28 Mar 2016 00:00:00 EST Using a fictitious scenario, we explore the Receiver Operating Characteristic metric. https://lettier.github.io/posts/2016-03-28-reelin-and-rocin-receiver-operating-characteristic.html https://lettier.github.io/posts/2016-03-28-reelin-and-rocin-receiver-operating-characteristic.html David Lettier Mon, 29 Feb 2016 00:00:00 EST Using only the WebGL, we implement an explorable environment containing two 3D Sierpinski tetrahedrons lit by per fragment lighting. https://lettier.github.io/posts/2016-02-29-triforce-overload-sierpinski-pyramids.html https://lettier.github.io/posts/2016-02-29-triforce-overload-sierpinski-pyramids.html David Lettier Wed, 17 Feb 2016 00:00:00 EST Analyzing the Texas Department of Criminal Justice death row inmate data, we text mine death row inmates' prior occupations. https://lettier.github.io/posts/2016-02-17-text-mining-in-r-death-row-prior-occupations.html https://lettier.github.io/posts/2016-02-17-text-mining-in-r-death-row-prior-occupations.html