About Author

Justin Wendlandt
Justin Wendlandt
I work for Wells Fargo, play a lot of video games, and program in many languages. [ more ] E-mail me Send mail

View Justin Wendlandt's profile on LinkedIn

Calendar

<<  July 2008  >>
MoTuWeThFrSaSu
30123456
78910111213
14151617181920
21222324252627
28293031123
45678910

View posts in large calendar

Recent Posts

Recent Comments

Comment RSS

Stock Quotes

WFC 23.92 +0.33 (+1.40%)
MSFT 25.98 +0.10 (+0.39%)
NVDA 12.49 -5.54 (-30.73%)
HAS 34.89 +0.41 (+1.19%)

XboxGamerCard

Jwendl
Jwendl
Gamer Score: 4725
Guitar Hero II (140) Rock Band (270) GTA IV (90) DYNASTY WARRIORS 6 (340) CSI-Hard Evidence (0) Culdcept SAGA (45) Overlord (420) Assassin's Creed (490) DEAD RISING (440) Halo 3 (535) Oblivion (390) Blue Dragon (25) Eternal Sonata (30) Tony Hawk's Project 8 (135) Gears of War (470) Crackdown (405)
Offline
2008-07-03T01:23:22-05:00
Last seen 07/03/08

Disclaimer

The opinions expressed herein are my own personal opinions and do not represent my employer's view in anyway.

© Copyright 2008

Creative Commons License

Header Photo

Ill Woes of Homework

April 6, 2007 13:33 by jwendl

I have recently spent many, many long hours on homework pondering theorems of matrices and polynomials for Advanced Algorithms. I think it was a first for me personally to learn so many topics "on the fly" so to speak. I just really wish there were good text books on these topics. If there were I would go buy them. For instance where can I find a good book based soley on matrix operations (such as Determinants, Vandemonde Matrix, Matrix Multiplication).

We got to play around with Determinants of matrices by taking a Vandemonde Matrix as such:

[math] V(x_{0}, x_{1}, x_{2}, -, x_{n-1}) = \left( \begin{array}{cccccc} 1 & x_{0} & x_{0}^{2} & x_{0}^{3} & - & x_{0}^{n-1} \\ 1 & x_{1} & x_{1}^{2} & x_{1}^{3} & - & x_{1}^{n-1} \\ 1 & x_{2} & x_{2}^{2} & x_{2}^{3} & - & x_{2}^{n-1} \\ - & - & - & - & - & - \\ 1 & x_{n} & x_{n}^{2} & x_{n}^{3} & - & x_{n}^{n-1} \\ \end{array} \right) [/math]

Transform it into :

[math] Det(V(x_{0}, x_{1}, x_{2}, -, x_{n-1})) = \left( \begin{array}{cccccc} 1 & 0 & 0 & 0 & - & 0 \\ 1 & (x_{1} - x_{0}) & (x_{1} - x_{0})*x_{1} & (x_{1} - x_{0})*x_{1}^{2} & - & (x_{1} - x_{0})*x_{1}^{n-2} \\ 1 & (x_{2} - x_{0}) & (x_{2} - x_{0})*x_{2} & (x_{2} - x_{0})*x_{2}^{2} & - & (x_{2} - x_{0})*x_{2}^{n-2} \\ - & - & - & - & - & - \\ 1 & (x_{n} - x_{0}) & (x_{n} - x_{0})*x_{n} & (x_{n} - x_{0})*x_{n}^{2} & - & (x_{n} - x_{0})*x_{n}^{n-2} \\ \end{array} \right) [/math]

And then prove using induction that it equals :

[math] \displaystyle\prod_{0<=j<=1}^{n-1}(x_{k} - x_{j}) [/math]

In the end this homework assignment took me approximately 40 hours in the span of 5 days. The efforts of this homework could not have been possible though without the assisstance of people in ACM who reminded me exactly how to do things like finding the determinant (which I had no idea how to do).

This homework assignment is not the only thing I got the luxury to slave about. I took an exam yesterday in Biology which appeared to be simple. Of course the last exam I said that for in Biology I earned a 15 / 40 grade on, so I am skeptical. I also have a history paper that is due today that I just wrapped up an hour ago titled Bringing Knowledge to the Masses and the Conflict that Develops. It's a cheesy title I know, but how else could I talk about my two favorite philosopher's (Marx and Kant). Then this next week will bring about an 8 page paper about William the Conquorer campaign from Hastings to London. The interesting perspective I get to write about is how the heck he got food because he definitly could not have carried that much food in that amount of distance.

Many of the topics lately that I have to work on are interesting, but it is near impossible to actually learn when I have soo much grunt work to do. So if anyone is wondering "where is Justin?" or "why does Justin look like a zombie?" the aformentioned issues are the pure reason for that. This weekend all I plan is sleep, my wife on the other hand informed me last night that my weekend is pretty much booked. Such is the life of a married, working, schooling, ambitious, late 20-something!


Be the first to rate this post

  • Currently 0/5 Stars.
  • 1
  • 2
  • 3
  • 4
  • 5

Add comment


(Will show your Gravatar icon)  

  Country flag

biuquote
  • Comment
  • Preview
Loading