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=Rhea Section for ECE 608 Professor Ghafoor, Spring 2009=
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=Rhea Section for [[ECE608|ECE 608]] Professor Ghafoor, Spring 2009=
 
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If you create a page that belongs to this course, please write
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== ECE 608 professor Ghafoor Spring 2009  ==
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== What's New==
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*[[Discussion about the availability of hw solutions online| Discussion about the availability of hw solutions online]] <B> - <SPAN STYLE="text-decoration: blink;color:red"> New discussion! </span> </B>
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*[[Plus_or_minus_discussion|Are you for or against using plus or minus grades?]]
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==TA==
 
==TA==
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===Reviewed Algorithms===
 
===Reviewed Algorithms===
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* [[Heap sort]]
 
* [[Insertion sort]]
 
* [[Insertion sort]]
 
* [[Merge sort]]
 
* [[Merge sort]]
  
 
=== Discussions ===
 
=== Discussions ===
 
Assertion made in lecture 3:
 
* "The base of a logarithm does not matter asymptotically"
 
    * So does that mean that given a set of log functions with different bases, we cannot say that one grows faster than the other?
 
  
 
Area to post questions, set up study groups, etc.
 
Area to post questions, set up study groups, etc.
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== 4-4 ==
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Attempted solution for 4-4 part (d):
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<math>T(n) = 3T(n/3+5)+n/2</math>
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We use the iteration method.
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Start with recursion tree:
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* Root node: <math>\frac{n}{2}</math>
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* First level: <math>3\frac{\frac{n}{3}+5}{2}</math>
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* Second level: <math>9\frac{\frac{n}{3}+5}{4}</math>
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* i<sup>th</sup> level: <math>\left(\frac{3}{2}\right)^i\left(\frac{n}{3}+5\right)</math>
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<i>Note:</i> above is not correct
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<math>\left(\frac{n}{3}+5\right)\sum{\left(\frac{3}{2}\right)^i}</math>
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== Randomization (and prob 5.3-3) ==
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As we've seen, Permute-With-All does not produce a uniform random permutation.  Curious to see how it affects the distribution of permutations?  Here's an experiment with the erroneous randomization algorithm:
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[[False randomize]]
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In the solution given for this problem, their argument is that <math>n^n</math> is not a multiple of <math>n!</math> for <math>n\ge 3</math>.  Intuitively, <math>n!</math> for <math>n\ge 3</math> includes more than one prime factor, namely 2 and 3, whereas <math>n^n</math> of course has only one.
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== Prob 5.4-5 ==
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Is there an intuitive explanation as to why the nested summations in the solution evaluate to a "combination"?

Latest revision as of 17:45, 22 October 2010


Rhea Section for ECE 608 Professor Ghafoor, Spring 2009

If you create a page that belongs to this course, please write

[[Category:ECE608Spring2009ghafoor]]

at the top of the page. You may also add any other category you feel is appropriate (e.g., "homework", "Fourier", etc.).

What's New


TA

Hamza Bin Sohail Office Hours: Tuesday & Thursday 4:30-5:30PM in EE306

Course Website

http://cobweb.ecn.purdue.edu/~ee608/

Newsgroup

On the news.purdue.edu server: purdue.class.ece608

One way to access: SSH to a server at Purdue (ie expert.ics.purdue.edu) and type "lynx news.purdue.edu/purdue.class.ece608"

On Ubuntu, you can use the "Pan" newsreader.

  • "sudo apt-get install pan"
  • Set "news.purdue.edu" as the server. You do not need to enter login information.
  • Type "purdue.class.ece608" in the box in the upper-left of the screen.
  • After a delay (half a minute?) the newsgroup will appear in the left pane. You can right click the group to "subscribe".

Reviewed Algorithms

Discussions

Area to post questions, set up study groups, etc.


4-4

Attempted solution for 4-4 part (d): $ T(n) = 3T(n/3+5)+n/2 $

We use the iteration method. Start with recursion tree:

  • Root node: $ \frac{n}{2} $
  • First level: $ 3\frac{\frac{n}{3}+5}{2} $
  • Second level: $ 9\frac{\frac{n}{3}+5}{4} $
  • ith level: $ \left(\frac{3}{2}\right)^i\left(\frac{n}{3}+5\right) $

Note: above is not correct

$ \left(\frac{n}{3}+5\right)\sum{\left(\frac{3}{2}\right)^i} $


Randomization (and prob 5.3-3)

As we've seen, Permute-With-All does not produce a uniform random permutation. Curious to see how it affects the distribution of permutations? Here's an experiment with the erroneous randomization algorithm: False randomize

In the solution given for this problem, their argument is that $ n^n $ is not a multiple of $ n! $ for $ n\ge 3 $. Intuitively, $ n! $ for $ n\ge 3 $ includes more than one prime factor, namely 2 and 3, whereas $ n^n $ of course has only one.


Prob 5.4-5

Is there an intuitive explanation as to why the nested summations in the solution evaluate to a "combination"?

Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett