Wednesday, September 23, 2009

Open-Source Math Tool: Sage

So life as a student has begun.

But not quite the same. For instance, I still have work pending; I still have people chasing after me, I still have products in the pipeline while several hours daily, I am usually in class.

Several days ago, professors from maths class that I'll take next semester (next semester, mind you!!!), emailed us 4-pages "diagnostic" test of our level of mathematics. I swear cold chills descended upon my spine. Not that I hate math or anything like that, but it kinda reminded me of those days of math homeworks which took me hours to finish, not to mention those blasted complicated sums which sometimes, unfinished, crept into my sleep...

So I turned to wikipedia to refresh my 'math memory' - if there's such a thing, and lo and behold, it didn't turn out as difficult as I thought. Differentiation, all kinds of techniques to arrive at it, etc. wasn't quite as horrible as I thought. And then I discovered "Sage". After unsuccessful attempts to use Maple or Mathlab or something without paying thousands of dollars (hey I'm only a poor student), I discovered an open-source alternative. Somewhat thankful, I'd like to see how it compares to other packages. After several frustrating download attempts with a download speed in the range of 5Kbps, I finally found a mirror closest to where I am, that allowed the download (almost 400MB) to finish in about 20 minutes.

It's good enough for me to start writing this blog post :) Let's just say it appeals to the geeky part of me - it requires a mini-webserver to run at port 8000, and requires one to have accounts to 'log in', and its worksheet, was clean enough that I could verify my answers to a complicated differentiation in half an hour. Intuitive words such as "diff" and "sin" and "cos" simply work. Well, they need brackets. And I suppose a few helpful buttons wouldn't hurt. But hey, engineers love command-line interface, right? This package has all that we can ask for...

Just thought to recommend this nifty package.

Now back to the books...

Friday, September 11, 2009

iPhone scare: black screen

These past few days, the iPhone I use had a black screen. For all purposes, it looked like it's dead, or switched off. But the alarm, which is set to go off at 6 everyday, made it ring and vibrate like crazy every morning and I couldn't turn it off. Calls were still going in, but I could see nothing. I could still use the cable to charge it and to sync it with the laptop and I'd hear the "clink" noise coming. So it wasn't dead, but neither was it functional.

They say Google's your best friend, and today it proved to be. A quick search on "iphone black screen" returns this page: http://seogadget.co.uk/iphone-display-blank-screen/. (The author had written, in his following post, that some site leeched off his post—I'm not going to do the same thing.. hence the link). But it basically says that you should hold down the "Home" round button at the bottom and the "Wake/Sleep" button on top, and the phone should reboot itself nicely.

It worked for me. Hope it saves someone the anguish, or having to find a pile of clothes or blanket in which to hide the vibrating iPhone. Read the comments in the link to amuse yourself :)