New Blog

I've started a new blog titled JeffComputes. Some of the old content from this blog has been ported over and all future content will be exclusive to the new blog. Thanks for reading!

Vim Highlight Shortcuts

Highlighting in Vim is super useful when trying to quickly see where something is being used. The following commands can be added to your vimrc file to make highlighting a breeze:

"{-- Commands to highlight the word under the cursor without moving the buffer
" view or cursor. --
" Case sensitive, partial match inclusive.
noremap hi :set hlsearch:let @/=''
" Case sensitive, no partial match.
noremap ho :set hlsearch:let @/='\<\>'
" Case insensitive, partial match inclusive.
noremap hu :set hlsearch:let @/='\c'
" Case insensitive, no partial match.
noremap hy :set hlsearch:let @/='\<\>\c'
"----}
" Command to remove highlighting.
noremap noh :noh

Podcasts for Software Developers

Some great podcasts covering topics related to software development:

• Ruby Rogues - The topics covered by this show are fairly broad and are applicable even if you are not a Ruby or even a web developer. For example, a recent episode discussed how to learn new skills as a developer. Conversational format; new episodes weekly.
• Coder Radio - Topics tend to be fairly non-technical and mainly revolve around recent news, mobile development and contracting. Conversational format; new episodes weekly.
• Hanselminutes - Scott Hanselman (well known Microsoft developer) interviews other developers in this podcast that covers a wide variety of topics. Interview format; new episodes weekly.
• FLOSS Weekly - Each episode focuses on a single open source project. The majority of each episode consists of an interview with a programmer or lead associated with the project. Interview format; new episodes weekly.
• Programming Throwdown - Each episode covers a single topic such as a specific programming language or technology. The discussion is kept fairly high-level and provides a good overview of the topic. Conversational format; new episodes monthly.

Vim Plugin Picks

The following are a few Vim plugins that really boost productivity with this fantastic editor:

• EasyMotion - Makes moving to a specific location a breeze; see it in action here.
• Buffet - My favorite plugin for moving between open buffers.
• CtrlP - Quickly open files within a project directory structure via fuzzy search.
• FuzzyFinder - Fuzzy searching for buffers, files, tags, etc.
• MRU - Simple plugin that shows a list of the most recently used files.

Quick note on using CtrlP with Fossil, modify the g:ctrlp_root_markers variable to include '_FOSSIL_' (and '*.fossil' if repos are kept locally with that extension). Now you can easily jump to any file in the open repo.

Parsing with Parsimonious

Recently I've been playing around with a parsing library for Python called Parsimonious. So far, I've been very impressed with it. Examples can be a bit hard to find; the following is a simple CSV parser:


The resulting output is the following:

{'gender': 'male', 'age': '26', 'name': 'Bob'}
{'gender': 'female', 'age': '30', 'name': 'Kim'}
{'gender': 'male', 'name': 'Joe'}

Hidden Fossil Features

The Fossil version control software has a few cool features that are somewhat hidden:

• RSS Timeline - Add .rss after a project's timeline URL to get an RSS feed; example.
• Link To Line Number - Add ?ln= to an artifact's URL to link directly to a given line number; example.

Thoughts on the PS4 Specs

The news broke about Sony's next-generation console last month. As expected, it will officially be dubbed the PlayStation 4. Unlike the PS3, the new console architecture closely resembles a typical gaming PC. The system will sport an 8-core AMD Jaguar CPU along with 8 GB of GDDR5 RAM and a next-gen AMD Radeon GPU.

Sony seems to be taking a safe route with this console. The PlayStation brand has had a history of being difficult to develop for, however, Sony is clearly focused on improving the process with this console iteration. Just take a look at the press release announcing the console; the very first section is titled "Gamer Focused, Developer Inspired" and touches upon the system's "ease of development". Good move Sony!

The 8 GB of GDDR5 RAM stands out as a major boon for game developers. Consider for a moment that the PS3 only had 256 MB of RAM, imagine what developers will be able to accomplish with a 32x improvement in memory. Additionally, the GDDR5 used by the PS4 will have a memory bandwidth of 176 GB/second compared to the 25.6 GB/second of the PS3.

Furnace Debugging

A few days ago, the blower motor on my Carrier Weathermaker 9200 furnace stopped working. Luckily, this model of furnace provides quite a bit of debugging information printed on the inside of the door. It was very straightforward to test the blower motor and confirm that it was not the source of the problem. After a bit of poking around with a multimeter, the only remaining possibility was the blower motor relay.

Resoldered Relay Trace on Control PCB

This furnace is equipped with a HK42FZ008 control board. This board holds the blower motor relay along with the control circuitry. There is a clamshell style case that snaps in place around the board; the relay is not accessible without removing this case. Once removed, the source of the issue was obvious. It appeared as if the solder around one of the legs of the relay burned up. The damage was enough to burn the PCB copper around the leg so that there was no electrical connection between the board and the relay. After testing the relay to make sure it still function properly, the solution was to expose enough copper of the trace leading up to the relay so that a large amount of solder could be added. Hopefully, the solder will be enough to handle the large motor currents that likely caused the issue in the first place.

The blower motor has been running fine ever since the repair. It is possible that an issue with the motor resulted in an unusually large amount of current draw causing the relay connection to fail. However, there is a 3 amp fuse on the motor supply line that was still intact. To my knowledge, the control board is original to the furnace which is about 20 years old. It may simply be a case of failure over time.

Vim For Health

Today I was watching a video on using Vim as a Python IDE when a comment about the health benefits of Vim caught my attention. Oddly enough, one of the reasons I decided to learn Vim was because of hand pain. After switching to Vim full-time, I have experienced less pain and could not imagine going back.

One additional step I took was to remap the left Ctrl key to Caps Lock. This has made a huge impact since I use the Ctrl key frequently and find the position of the key to be awkward. Hitting the normal key requires either a left hand movement or curling up the pinky finger; it's a recipe for hand cramps! The Caps Lock key being on the home row feels more natural. I use SharpKeys to handle the remapping on my Windows machines.

Qt 4.8.4 and MinGW Quick Start

The following are instructions for installing Qt and compiling a demo application using the MinGW toolchain:

1. Download the Qt 4.8.4 libraries installer here.
2. Run the installer. If a warning message about the version of the w32api.h file appears ignore it and continue the installation (my install is version 3.17 and appears to work fine).
3. By default, the installer does not add the Qt toolchain to the PATH. Instead, it provides a custom command prompt environment called the "Qt 4.8.4 Command Prompt"; launch this command prompt from the Start menu.
4. Now we can try compiling an example; from the Qt command prompt, navigate to C:\Qt\4.8.4\demos\textedit.
5. Execute the command qmake; this should generate a makefile.
6. Build the example using the command make.
7. If everything goes correctly, textedit.exe should now exist in the debug directory; launch the demo application.

That’s it! Your machine is now ready to build Qt apps using MinGw.

Vim Zoom Hack

When writing large documents with a text editor, it is sometimes useful to zoom out and get a high-level view of the file (I believe Sublime Text has a feature called minimap that does this). This functionality can be added to gVim with a simple vimrc addition (to my knowledge, this will not work with regular Vim).

Add the zoom out command with the following: noremap <Leader>zo :set guifont=courier_new:h4<CR>

Add the zoom in command with the following: noremap <Leader>zi :set guifont=courier_new:h10<CR>

Adjust the font type and normal size as desired. Not the most elegant method but it works. Please note that split window sizes may be affected during the zooming process.

PopPage

Recently, I had a need for a very lightweight static website generator. The idea was to have Asciidoc and Pandoc handle the markup to HTML conversions while the generator would simply apply the HTML content to a Jinja2 template. The result was PopPage, a simple command-line driven website generator. It plays nicely with native Windows batch scripting and I plan on providing a few examples in the GitHub repo shortly.

Docopt

While browsing YouTube recently, I stumbled upon a video about a great third-party Python module called Docopt. It greatly simplifies writing command line utilities; instead of writing custom logic using the standard library optparse or argparse modules, you simply write the usage docs for the utility and Docopt handles the parsing. Check out the documentation; there are some great examples that really showcase the power of this module.

Raspberry Pi First Impressions

Received my first Raspberry Pi the other day. I ordered two Model B devices from Newark and, despite the high demand, received them in about a week.

My intended use for the first R-Pi was to serve as a mini-HTPC for my basement TV. I tried both Omxplayer running on Raspbian and Raspbmc. I was very please with the performance of both; they were able to stream videos from my NAS with no issue. Unfortunately mplayer on Raspian currently does not support GPU acceleration on the R-Pi and lacks the horsepower to be of any use. For now, Raspbmc will likely remain the frontend of choice for the HTPC.

Overall, the value of the R-Pi is amazing! For $35, this device is an absolute bargain and a must have for any tech DIYer.

Vim Scratch Buffer

Opening a scratch buffer in Vim can come in handy. The following vimrc addition works well: nnoremap <Leader>sc :e scratch<CR>:setlocal readonly<CR>

It is especially useful in combination with the run shell command shortcut once Vim is configured to change to the directory of the current file with the following vimrc addition: autocmd BufEnter * execute "chdir ".escape(expand("%:p:h"), ' ')

The advantage this named buffer has over the [No Name] buffers created by :enew is that newly created scratch buffers will not affect the path of existing buffers. This can be useful if you later want to save the contents of your scratch buffer.

Vim Run Shell Command

Here is a nice simple vimrc file addition that will execute a line as a shell command and read back the output into the buffer: nnoremap <Leader>rl yy:r!<C-r>"<CR>

Fossil Command Line Tips

For small projects, Fossil is a great choice for revision control. Fossil’s command line interface is very easy to use and plays nice with utilities like grep, gawk and xargs. The following are examples of common operations:

• Check in only edited files: fossil changes | grep EDITED | gawk '{print $2}' | xargs fossil commit -m "Added feature X."
• Add only files with name containing "pattern" to repo: fossil extras | grep pattern | xargs fossil add
• Move files in repo to match move on filesystem: fossil changes | grep MISSING | gawk '{print "fossil mv " $2 " subdir/" $2}' | sh

New GoogleCL Blog Process

First post using a new blog process! All new posts will be written using Asciidoc text files. Each file is then converted to HTML and uploaded to the blog via GoogleCL. The whole process is automated using Python.

I’m hoping this new workflow will make writing new posts more efficient in turn leading to more frequent updates.

PyPy Intro

David Beazley gave an excellent introductory talk about PyPy at PyCon this year. I knew very little about PyPy going in and David really helped clarify the goals and approach of this ambitious project.

There are several other PyCon talks that discuss this project in more detail:

• Why PyPy by example
• How the PyPy JIT works
• How to get the most out of your PyPy

Also, check out the full list of videos from PyCon 2012 for other great talks.

Tweaking Gnome Panel

My HTPC is a Linux box running Ubuntu 10.04 and I love it. To give it a more couch-friendly interface, it's now running Avant Window Navigator. I wanted to keep the top Gnome Panel available but hidden with a 1 second unhide time. To tweak these settings, do the following:

1. Open gconf-editor.


2. Navigate to /apps/panel/toplevels/top_panel_screen0.


3. Enable auto_hide.


4. Set unhide_delay to 1000.