August 16, 2012

debugging matlab mex

One thing I’ve been doing a bit of lately is debugging MATLAB mex files; it seemed worth documenting. The broad strokes:

recompile all mex codes with ‘-g’
quit MATLAB
From a command prompt, run

$ /Applications/MATLAB_R2012a.app/bin/matlab -Dgdb
[snip]
(gdb) run -nojvm
>> run_your_mex_file

This gives debugging output. If there is an error in the code, you’re dropped back to a gdb prompt, where you can continue debugging in a semi-normal fashion. Typically, I end up doing a ‘where’ to get a stack trace, and debug from there more-or-less like usual.

July 27, 2012

Meta post - How my blog works

A while back, Sharvil requested a quick overview of how I post stuff to my blog, so I thought I’d post a rundown of it.

At the base, I use a git repository to store files named entryNNNN.txt. Each has the basic format:

title: Meta post: How my blog works
date: 2012/07/27
category: software
---
A while back, Sharvil requested a quick overview of how I post stuff to my blog, so I thought I'd post a rundown of it.
At the base, I use a git repository to store files named entryNNNN.txt. Each has the basic format:

To start a new post and fill in some of this, I have a script called ’newentry.sh’, which determines the latest entry number and adds one to get a new filename (eg, entry0081.txt).

June 27, 2012

More cracking D-Link Files

Somehow, in the process of a router reconfiguration, I reset the password without the new password getting saved into 1Password. So I found myself locked out of my own router. I was about to reset it, thinking, “Hey, at least I have a backup of the settings from 2 nights ago!” and then realized, “I bet that settings file has the password right in it.”

Googling around a bit turned up this guy, but he only wrote VBA and a Windows binary. His pseudo-code looked pretty easy to translate into Python, so I did just that. Here’s the result: D-Link DIR615 B2 v2.25 Decoder (no encoder, yet…)

June 13, 2012

McCormick Interview - Outreach 101 + QUALS

I was interviewed and given a semi-prominent placement in Northwestern’s McCormick Magazine for the outreach work that 2011-2012 NU-IEEE President Curtis Wang and I have put together. Permalink to article. It was a really nice writeup and really great to get to throw out a mention of Joyce Stark!

In other news–I had a crazy couple of weeks due to preparing for (and eventually, taking!) my PhD qualifying examinations. They consist of a panel of three professors questioning me on intricacies of material that I’ve been learning over the last couple of years, namely: Numerical PDE methods, Analytic PDE methods, and optimization. Professor Kath had a particularly interesting question where I derived the heat equation from a minimum-energy problem. The exams went for 95 minutes, followed by a 5 minute deliberation, after which each professor came out with handshakes and congratulations.

May 26, 2012

Numerical Recipes & Scientific Libraries

I attended a talk on how to use Quest, Northwestern University’s TOP500 supercomputer(At least during June 2010). Most of it was a routine introduction to MPI, but one interesting question raised was what routines we should be using in our scientific computing codes. A lot of holdouts were still using [ Numerical Recipes] for their research-level codes, which strikes me as a backwards way about it. Numerical Recipes is a starting point, and probably not the best thing to use: it has awful licensing and might not even be that reliable!

April 13, 2012

Integrating Sparrow and Aperture/iPhoto

In my recent quest to take on digital photography, I’ve been using Apple’s Aperture to store download my pictures and do basic manipulation on them. It’s been working great, except that emailing is a pain because Apple hardcoded the email clients to:

Apple Mail.app
Eudora (really!?)
America Online(!?!)
Microsoft Entourage
Microsoft Outlook

while I’d prefer to use Sparrow, a lightweight client that Sharvil got me hooked on a while back. Rather than continue to use Mail.app to send pictures via email, I found out that Aperture actually uses some AppleScripts to do the actual sending of the email. That got me thinking: I just need to change the script to mail using Sparrow, instead of Mail.

April 2, 2012

chicago 2012 marathon

I’ve signed up for the Chicago 2012 Marathon with Team To End AIDS or my donation page–PLEASE! every bit helps!). It’s a bit of an unusual choice, probably, to not run for the American Lung Association(I have asthma) or the American Cancer Society(my dad is a survivor.) But it’s actually been a good opportunity to learn a bit more about the current state of AIDS, AIDS policy, and what it’s like to live with it. I’ve also had some really good discussions about it with people it would not have come up, so it has been nice all around.

March 29, 2012

digital photography

Recently I’ve decided to dedicate a slight bit of time to get a bit better at taking pictures. I’d always wanted to get a truly nice camera, and the opportunity presented itself, so I decided to go for it and bought a Nikon D5100 DSLR. I also ended up getting a complete steal on the Nikon 55-200mm DX VR lens, which was pretty awesome. Project 365 would be a great move from here, since I’m certainly no photographer, but it’s been fun just learning about it all the ins and outs and how it all works together. In any case, I did start a Flickr: drtraviscj account which I’ll be posting stuff.

March 29, 2012

fibonacci miles and kilometers

In my running, I have been trying to keep track in kilometers. This presents a couple problems: Somehow, my mind still thinks in miles, which is weird because I do not really have /that/ good of an idea exactly how far a mile is, either. Or someone wants to know how far a 5k is. Or, when I was running the 2011 Chicago Marathon, there would be kilometer postings between the mile markers. Anyway, it is handy to convert between them, but a bit of a pain.

March 26, 2012

tjtestharness - a language-agnostic DVCS unit-test/continuous integration tool

I’ve been wanting to have a way to visualize which unit tests(or sets of them) passed for a given commit, if for no other reason than the sense of accomplishment from watching boxes turn yellow, then green, as they pass tests. The trouble is, I write code in a lot of different languages for a lot of different projects. I also don’t want to bother with running unit tests individually–I want them to run as I perform commits.