I love seeing the Facebook notification light up on my birthday. Who doesn’t? But my guess is that most people can’t help but feel some sort of repetition and monotony when clicking through. Don’t get me wrong; I enjoy every single post on my Facebook timeline. It makes me feel loved, you guys.

With the Facebook Graph API and a couple lines of JavaScript, I extracted the text from the Facebook wall posts on my last birthday. Without any names or formatting, feels a little different, doesn’t it?

/^happy b(irth)?day,?( paul( shen)?)?!*$/gim

47/96 matches! I could easily list out the strings this regex matches and it would cover 50% of the wall posts.

I could go on and sarcastically categorize the remaining 50% but you get the point. Again, I’m grateful for all the birthday wishes; I just thought it’d be something interesting to examine. Maybe run something similar on your next birthday! Personally, I’m not much of a Facebook birthday wisher unless I have something that doesn’t match the regex above. But then I also don’t like fun (jk!) If everyone was like me, it’d be a gloomy place indeed.

The usual

I’m serious this year. I might’ve said the same thing last year, and the year before, and now to think about it, the year before that too.

• Sleep earlier
• Exercise — couch to 5k style
• Spend less time on YouTube
• Take more photos
• etc.

Okay okay, here are some more concrete goals.

Write more

Since I’m already here, the last post on this site (let’s not call it a blog) was over a year ago. I used to redesign my blog every time I visited it but this one still doesn’t look too bad (though I should renew that Typekit subscription). Let’s aim for twelve thoughtful posts by year end.

Record a “CD”

No, I don’t plan to become the next Justin Bieber but I’ve got a pair of mics, a six-note range, and a guitar. Should be able to hammer out ten covers by the end of year. We’ll call it Me and My Guitar. or He and Her. TBD.

Make stuff

I’ve lost touch with my self-proclaimed creative art and design side. Keeping this one vague but 2011 was a year devoid of any side hack projects.

I could go on but this will suffice for now. Not the most thoughtful post but it’s a start to break out of my lazy rut.

rut… that’s kind of a cool word.

Grids are not anything new; the book gives a two-page history which mentions that the history of grid-based frameworks trace as far back as 9000 BCE. The typographic grid is a trademark of the International Typographic Style. Bringhurst has a chapter on “Shaping the Page”; Josef Müller-Brockmann has a great book on grid goodness in graphic design. Nowadays, look around the web and you’ll find countless collections of “grid web-based design inspiration” and articles of varying levels of quality.

Vinh states in the beginning, “[w]hat’s not yet fully addressed is how the use of the typographic grid applies to the mechanics of digital design for the World Wide Web.” The book is surprisingly focused on this topic, investigating grid design in the context of the web. And even with the plethora of grid design resources, the book feels fresh. There isn’t any discussion of code implementation (phew) and a lot of what is well-covered in other books is left alone.

After a little history and background, the book takes a very hands-on route by walking through the design of a website; the calculations and rationale are explained in detail. The more I play with grids, the more comfortable I find myself reasoning and executing. Practice makes you better but having a little insight into the process of someone so experienced is affirming and educational. It comforted me that the overall tone is very calculated; a lot of numbers are thrown around and everything is logically reasoned. Yet, a well-executed grid design appears simple and inherently correct.

What started as a freeform ramble seems to have turned into happy acclaim. But, the book is definitely worthy of approval in my opinion. There is a lot beyond what is in the book but as a foundation for grid principles on the web, Ordering Disorder gets a spot on my bookshelf.

The following are some vim tips I find useful that I’d like to share, assuming you have the basics down: h, j, k, l, w, e, b, 0, $, %, g, G, i, I, a, A, o, O, v, y, d, c, r, p, P, and so on.

Use f to move to a specific place in a line

To move to the second ‘w’ in this line (with your cursor at the start of the line), type fwfw
[vimdoc] moving to a character

Use tabs and splits

As important as learning to create splits and tabs is getting comfortable navigating between them.
[vimdoc] splitting windows
[vimdoc] tabpage

Mark your place

Let’s say you are working on one place of a long file and need to navigate to another place in the file, but eventually need to come back to the current location. Mark the current location by typing mm (m followed by any character) and move around the file at will. Once you’ve done your thing, type ‘m (replace m here with the character you chose before) to move your cursor back to where you marked before. This saves a lot of time as well as cognitive cycles.
[vimdoc] using marks

Get rid of the suck by recording commands

Ever find yourself repeating the same keystrokes over and over? Type qq. Do your keystrokes. Type q. Move to where you want the keystrokes repeated and type @q. Go ahead and try 10@q or even 100@q. If you choose your keystrokes carefully, your recorded commands can be quite adaptive.
[vimdoc] record and playback commands

:mksession

If you like gvim but get frustrated that screen doesn’t play nice, :mksession is your answer! Also, :mksession is great for reloading all the files you have open.
[vimdoc] sessions

Move the view with z

If you find your cursor at the top or bottom of the screen, just type zz or zt to scroll so that your cursor is at the middle and top of the screen respectively. This is useful when you search for a function name but the function ends up at the bottom of your viewport.
[vimdoc] scrolling around

Complete your word with ctrl-p

While in insert mode, press ctrl-p to complete a word that already appears in your open files. If there are multiple possibilities, vim lets you select the correct one from a dropdown.
[vimdoc] completing keywords from different sources

The following are the best classes I’ve taken at CMU; I learned something during these classes and enjoyed it too.

• 15-251 Great Theoretical Ideas in Computer Science (von Ahn)
• 15-410 Operating System Design and Implementation (Eckhardt)
• 57-209 The Beatles (Schultz)
• 60-412 Interactive Art & Computational Design (Levin)

In general, I found more classes annoying than interesting, more tedious than educational, but I guess it’s all part of the process. I met and interacted with lot of cool students and professors from whom I learned both personally and academically. I really enjoyed my independent studies with Eric Paulos and Stacie Rohrbach. I question my decision to receive my HCI degree but if nothing else, I met a number of neat people with similar interests. I was a purely technical student coming out of high school (math and sciences) but that definitely changed over the last four years as I poked around the design spectrum.

I got a bunch of teaching experience, year and half of tutoring and another year and half of TAing. This was definitely a cause of lot of frustrations: grading, bad professors, and students who didn’t care about the subject matter, only about getting the homework completed. But it also felt right interacting with the students who did care, definitely something I want to pursue in the future.

I will never regret my decision to join Soundbytes, my a cappella group, from semester one. I met some of the coolest people I know in the group and really enjoyed being a part of something family-like. We had our ups-and-downs but that’s all part of the ride.

With the CMU name tag, I was able to score nice summer internships at Apple and Facebook. My summers provided great exposure to the industry as well as the west coast. In August, I’ll be starting full-time as a User Interface Engineer at Facebook, more or less continuing from last summer.

I don’t know if I’m going to return to academia in the future, perhaps for a media arts program or what not, but I’m ready to move on after classes. There’s something exciting about school, with all your projects, deadlines, and social life as well. But I’m ready for the post-college life. Let’s see what happens.

For example, if I want to translate an object by (3,4,5) and then rotate it 45 degrees around the z-axis, I would use the following code to retrieve the transformation matrix. Notice the order of the transformation functions.

0.707107 -0.707107 0.000000 -0.707107
0.707107  0.707107 0.000000  4.949748
0.000000  0.000000 1.000000  5.000000
0.000000  0.000000 0.000000  1.000000

For my last college spring break, a group of my friends and I took a trip to Puerto Rico. I thought this was a good excuse to purchase my first compact camera. After doing a good amount of browsing, I settled with the Canon S90.

Size

The size of this camera is perfect. In fact, the size was what made this an easy choice over the Panasonic LX3. As good as the S80 was, the camera was just not convenient to carry around. The S90 slips in and out of my pocket and there’s no lens cap to worry about (something the LX3 has). Again, if nothing else, the small size of the S90 is easily a deciding factor versus most advanced compacts. If the scenario screams for image quality, I’ll shoot with my SLR.

Image Quality

I was somewhat relieved to find the image quality not as good as my Canon Rebel XT or I think I would have been quite sad, although not too surprised. There is significant noise even around ISO 400. I was surprised by the number of ISO increments starting from 80 up to 3200, with two settings between each each multiple of two, e.g. 200, 250, 320, 400. The camera shoots RAW, something I really appreciate. Additionally, the camera has image stabilization, which I assume helps with the longer exposures.

The S90 has a fast lens with a maximum aperture of f/2.0 but at the long end, the lens only opens up to f/4.9. The camera has a 35mm zoom range of 28mm to 105mm, which is quite versatile. I find my personality tends to feel home in the 20-50mm range so this camera satisfies my wide-angle desires. And with the wide aperture comes all its advantages, including having good video capture. Yes, the S90 does not do HD videos but it definitely performs well in low light situations.

Interface and Operation

The control ring in front of the camera is interesting. It’s not as radically useful as I had hoped but it serves as another dial input, which is always welcome. For my personal settings, I let the control dial in front of the camera control aperture while the traditional dial controls exposure. There is a customizable shortcut button, which I assign to ISO. These settings are for aperture priority, which is how I usually shoot. Overall, the interface and controls are intuitive. As with the S80, I think the dial controls make navigation and selection easier, and having two of them just makes it better.

Notable

The camera has a beautiful 3″ LCD screen. The colors are vivid and the resolution is sharp. My friends commented that my pictures looked better than theirs if no reason other than the screen itself. The camera also looks nice; it’s black all around and has a clean feel. I use a 3″ GGS screen protector to cover the LCD screen, which seems to work well.

Overall, I’m quite satisfied with the purchase. There isn’t anything that I can point out that would deter me from making the same purchase.

And if you’re at all inclined to check it out, here’s a link to the Canon PowerShot S90 on Amazon. Yes, okay, it’s a referral link.

From Wikipedia,

Optical flow or optic flow is the pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by the relative motion between an observer (an eye or a camera) and the scene.

The video above augments a water drop with a fluid simulation activated by the water’s optical flow. Meta, if you will. In a way, the augmentation shows something that is present but invisible, specifically the derivatives of the motion, the forces acting on the water. The water drop source video is on YouTube.

In mathematics and physics, we’re often concerned with derivatives, the rates of change. If we represent x as the position of a particle, d’(x) represents its velocity and d”(x) represents the particle’s acceleration. In the physical world, at any point of time, we see x, the instantaneous position of any object. But the world is not static; things are constantly moving, whether affected by natural forces or a consequence of our actions and decisions. This project makes visible the d’(x), the change of position, with a fluid simulation. There’s something beautiful about continuity.

Other Videos

Implementation

The following code extracts the derivatives from the CvMat into double arrays.