So, I know that I’ve been harping on this a bit, but I’ve re-written my M-Set renderer in C, so it’s faster, and I’ve added a few more command line flags to make it easier to use.
Get the code here.
M-Set update
Leave a reply
Category Archives: Software
More Mandelbrot
I just recently revisited the M-Set code from my Perl Snippets post. The code I had was pretty ugly, so I decided to rewrite it in Python. The result is not only a lot cleaner and easier to understand, but it’s also a lot faster:
$ time python mandel.py > \dev\null real 0m0.051s user 0m0.036s sys 0m0.010s $ time perl mandel.pl > \dev\null real 0m3.518s user 0m3.463s sys 0m0.029s
You can find the code here.
This script works well for zooms, as long as you stay below a few thousand iterations. The following picture was generated with x=-1.1887204, y=-0.3032472, width=0.01 and 150 iterations.
Conky Calendar with Date Highlight
Since I got a new desktop a month or so ago, I’ve been running Ubuntu as my main operating system, and am using Conky for a nice heads-up-display. There are a lot of articles on the web about both Ubuntu and Conky, but one thing I couldn’t find a good, accurate how-to on was getting a calendar that highlighted the current date. While getting the calendar is easy using the cal command, actually getting the date highlighted is somewhat hard, and all of the articles I found suggested methods that broke in various situations. However, I managed to get it all worked out, and have a beautiful calendar that looks like this:
After the jump, I’ll give you the code and explain how it all works. Continue reading
GPSd under OS X
Update 7-13-11: I’ve posted an updated set of instructions on getting GPSd to compile on OS X here; this post will remain for archival purposes. For information on installing GPSDrive, see this post.
So I recently picked up a cheap GPS module on Amazon. It was about $30 with shipping, and I got a neat little dongle which connects over USB to my computer and communicates with software. It didn’t come with support for OS X (although interestingly enough it shipped with Mac OS 8 and 9 drivers), but it promised to send generic NMEA-0183, so I wasn’t too worried.
When it showed up, some quick software probing revealed that it houses a usb to serial adaptor (a Prolific PL-2303, which I’ll get to in a bit) and a gps module that’s configured to send NMEA strings through the virtual serial port. This sort of information is compatible with a host of software, but most of it is commericial, and only available at a considerable price.
Luckily, there’s a wonderful open source project called gpsd which provides support for a wide raft of devices and protocols, and talks to an even wider assortment of software. Primarily, I wanted to be able to get my gps to talk to the network scanner Kismac, and Randall Munroe’s cyborg.py script. Both of these were built to take information from gpsd, so I was in business. However, gpsd, which is designed to play nicely with Linux, takes some coaxing under OS X. This is meant to describe how I got it all running. Continue reading
Fast and Simple Stock Quotes Using Perl
One of the things that makes perl so powerful and fascinating is the huge number of modules that are available online, especially through the CPAN repository. Today I stumbled upon one called Finance::Quote, which does one thing, very simply: it retrieves stock (or mutual fund) quotes. You feed it a ticker symbol and it gives back a hash with all sorts of information, but most importantly, the price. I’m going to show how to use this to create a command line tool that will grab an up-to-the minute stock quote for any ticker symbol you give it.