Starting a web server and other PHP tricks
Start PHP webserver (in current directory): php -S localhost:8080 # starts http server on port 8080 Start PHP prompt (with illustrating example):
Screen capturing with PhantomJS
PhantomJS is a headless browsers that you can use, e.g. to test web UIs and to screen capture webpages. I will focus on the last use case. Since PhantomJS knows how to execute Javascript, it can create a screen shot…
Twitter HyperLogLog monoids in Spark
Want to count unique elements in a stream without blowing up memory? In more specific words, do you want to use a HyperLogLog counter in Spark? Until today, I’d never heard the word “monoid” before. However, Twitter Algebird is a…
Easiest way to install a PostgreSQL/PostGIS database on Mac
Installing Postgres+PostGIS has never been easier on Mac. In fact, it is now an app! You download the app-file from postgresapp.com, place it in your Applications folder, and you’re done. Really. If you think that was over too fast If…
Poor man’s wget
The command wget is useful, but unfortunately doesn’t come preinstalled with Mac. Yeah, you can install it of course, but if you’re doing it from source, the process has a few steps to satisfy all the dependencies; start by configure…
How to set environment variables for single process
In bash, you simply prefix a command with one or more XXX=”YYY” pairs, e.g. $ A=”B” X=”Y” python print_env.py … A=B X=Y The code for print_env.py: import os for ev in os.environ: print “{0}={1}”.format(ev, os.environ[ev])
The purpose of language by Chomsky
In the following Google video, Noam Chomsky raises and answers the interesting question: what amazing insights into language have linguistics revealed, which the public does not know about?. He answers that human natural language was propably developed to support the…
Recursive relationship between humans, computers and human societies
This post is influenced by a talk I had with Marcos Vaz Salles and a debate that happened between Foucault and Chomsky in 1970. The relationship between humans and societies is a recursive relationship. Human beings influence societies and societies…
1970 debate between Noam Chomsky and Michel Foucault
Chomsky has written and said many things, namely on the topic of linguistics and politics. In an attempt to get an overview of it all, I searched for the term “overview of chomsky’s work” and found post on znet called…
Word-count exercise with Spark on Amazon EMR
This is a mini-workshop that shows you how to work with Spark on Amazon Elastic Map-Reduce; It’s a kind of hello world of Spark on EMR. We will solve a simple problem, namely use Spark and Amazon EMR to count…