Structure and Interpretation of Computer Programs

Siminal MIT book; is licensed under Creative Commons.

PDF version here:


HTML5 version:


Older version (not updated since 2010) by Ian Eure:; download:


Meetup e-mail

Social media

We're on Facebook! And Twitter! And Google Plus…

• Facebook: • Twitter: • Google+:


While may be free for you, it's not free for organizers (me especially). Myself and the other organizers volunteer our time because we all like hiking, but at $150/yr, Meetup is quite a hit to the pocketbook, especially for what they provide. You can help cover the costs for the group by donating: either feel free to donate some cash next time you see an organizer (drop a mention to me so I remember to bug them for it), or donate online through Meetup:

IPv6 for your home network

In /etc/nsswitch.conf: Replace mdns4_minimal with mdns_minimal Add mdns to the end of that line

Downtown Desert Yoga review

My first experience w/ Bikram yoga (AKA hot yoga) was at DDY. I had taken a few non-heated classes before,

I’ve been at both the old studio on Main Street and the new one on Alameda, and while I liked the old place better the new one has grown on me. The heating/cooling system is significantly better—it gets hotter for the hot yoga classes and cooler for non-heated classes. There are hardwood floors throughout, and you don’t feel gross walking barefoot throughout the studio.

Virtualenv with Python 3.3's venv

However, Python 3.3's venv module is easily used to create custom venv setup scripts. Vinay Sajip has done just that with Use the script as you would

ThinkPad T530 first thoughts

No indicator lights for AC power, battery status, or charging status on front.

No caps lock indicator (only noticed while in Windows).

Large, bulky. But surprisingly lightweight, compared to tablets like iPad or Nook Color.

Hate the lack of grouping on function keys, no color on Enter, Function keys, or escape. Cannot feel bumps on F and J keys.

Really fast wake from suspend.

Took Linux disk from X61 tablet, installed into T530 w/out problems! Turned off UEFI and enabled legacy boot. Did not need to reconfigure trackpad, screen, etc.

tp-smapi-dkms does not work. Missing being able to set battery charging thresholds, etc.

An Albuquerque Code 66 2012 debrief

A couple months ago, I participated in Albuquerque's Code 66 Hackathon.

What's a hackathon? My one sentence definition: a weekend where the goal is to go from idea to demoable product (usually a MVP, but not exactly) as quickly as possible.

One of the progressive civic movements in the past decade is that of civic open data. That is, data about your city & government should be freely accessible for use by citizens, who are free to do. After all, it is citizen tax dollars that pay for it!

This June, the city of Albuquerque was one the latest cities in the country to start its open data initiative (Dear Las Cruces, Ruidoso, Roswell, El Paso, et al—what exactly are all of you doing?), and they've published several open data sets.

Oh, and if you figure out a creative way to use this data, Albuquerque has a $30,000 apps challenge with, as you might have guessed, a $30,000 grand prize!

At the hackathon this past summer, Zerek Welz, Chris Huges, and myself met at the event and eventually came up with Where's the bus!? Albuquerque.

A week with Verizon's HomeFusion

Living in the tree-less high desert, I have line of sight to two different cellular towers, one to the direct north and one to the south–southeast.

Generate entropy for your server

Discuss ekeyd, haveged, etc

How many times a week do I use such and search search engine?

Write post here.

Backing up your account

To backup my Twitter account, I use ThinkUp, which also happens to backup my now-dormant Facebook account. Take that, corporate data silos!

Because of the recent (late-2011) downtime on, and with the release of StatusNet 1.0, I figured now was as good a time as any to seriously setting up my own federated µ-blogging instance. With the heavy focus on federation and autononous Web principles, I always assumed that it'd be both easy & obvious to get data back out of

One word: meh. has a backup feature, but it doesn't work quite right. For example, I could only fetch dents going back 4 months.

Preview of changes to | StatusNet

Camera at a mountain Webcam on the Web

Theming Apache's mod_autoindex

Doing WHATEVER URLs the right way w/ jQuery Mobile

A JSON proxy for the OpenStreetMap API

Developer Discussion - JSON-output for xapi

Multiprocess in modern browsers

Internet Explorer

First multi-process browser? MSIE4?



Getting through Python 2's Unicode problems

Color on the Console

dstat grep htop pydf


bash - less emulate a TTY to preserve piped color output - Super User

Movie Review: Michael Madsen's Into Eternity

With Chernobyl's 25th anniversary a few weeks past (ignored, for the most part, by Western media), and the Fukushima nuclear disaster fresh in everyone's minds, now is as good a time as any think about nuclear energy's role in our civilization. Into Eternity, a Finnish documentary released in 2010, takes a very unique look at the nuclear power industry, one not typically thought about. Rather than nuclear proliferation or the plants themselves, it focuses on the geologic storage of spent nuclear fuel (aka SNF), in particular, Finland's Onkalo repository.

The movie skimps on technical details, some of which I will talk about here.

Nuclear waste can be divided into two levels: high-level and low-level. Low-level nuclear wastes include things such as clothing, plant construction materials (e.g. concrete) and machinery that have come in contact with anything nuclear.

High-level nuclear wastes include spent nuclear fuel and chemicals used to process and create nuclear fuel. The movie focuses on spent nuclear fuel, which in most nuclear power plants are things called fuel rods. Fuel rods

At the moment, the US does not have a storage plan for spent nuclear fuel. There is one geologic storage site, the Waste Isolation Pilot Plant in southeastern New Mexico, but the site is relatively small and destined for storing the generation I nuclear wastes of America's nuclear weapons programs, not that of commercial reactors. A larger site, Yucca Mountain, well isolated in the Nevada Test Range (where nuclear weapons were tested for decades, and much contamination remains), was shelved in 2010 by the Obama administration, leaving America's nuclear energy industry without secure storage for its spent nuclear fuel.

Much of the topics Into Eternity touches, such as communicating the dangers of nuclear wastes stored at sites via markers and monuments, has similarly been discussed for the US' Waste Isolation Pilot Plant.

Drupal 7 upgrade post-mortem

This weekend, I upgraded Samat Says (this blog, in case you missed the memo) to Drupal 7.

For my Drupal 4.6/4.7-based site, I had created my own theme, Sands. Lack of time prevented me from porting Sands to Drupal 5 or 6, and it's unlikely it will be ported forward. I'm probably going to recreate it with one Drupal 7's many starter themes, however.

Patient care in the ICU in terms of vectors and topological spaces

Biomedical Informatics, Medicine

A few weeks ago, Timothy G. Buchman gave a talk at the Columbia DBMI weekly research seminar. During the QA session, someone asked why patients in intensive care units (ICUs) were given such “extreme” treatments, often causing them to develop new health problems and complications, keeping them in the hospital. He replied with this wonderful mathematical metaphor about patient care.

You are a point in an n-dimensional space. Each dimension is some vital sign or homeostatic attribute, e.g. blood pressure, blood glucose, temperature, etc. Homeostasis is defined a polytope in that space. As you do the various things of life, your point moves within the space defined by that polytope. For example, when you eat, your blood sugar goes up, and the point moves along in the blood sugar dimension; when you take a cold shower, your body temperature is reduced, and you move along in that dimension. Young people have a large space inside their homeostatic polytope

When you leave this homeostatic polytope, you're considered “sick.” If you travel to far from it, you die.

People who enter the ICU have points that are moving away from their homeostatic polytope. Their movement away can be represented as a vector, representing how quickly their condition is deteriorating.

Treatments in the ICU represent vectors that try to point you back towards your homeostatic polytope.

SamatsWiki: DraftBlogs (last edited 2016-08-19 22:04:14 by SamatJain)