Penny piles

Noticed the mail from professor about problem solving.
I'm not sure whether I've posted some of my thoughts about problems with
mathematical or programming nature, but to make sure with that I thought I should
make another post.  Hope I can submit this post in time...

Penny Piles:

I'll skip the detailed explanation of the problem due to the time (copy of the pdf is linked to the mail
by professor), but core aspect of this problem is to produce a number between 0 and 64 in
either of two piles of pennies, starting from 64 on one and 0 on another, by only halving the even number of the pile.

Since the total number of pennies would not change from 64, and there are only two possible piles,
we know that the sum of the two pile would be 64.  Due to this nature, our work can be halved as we
notice that by proving how to make a pile from 0 to 32 it would also prove that of 33 to 64.
We can say a same thing for numbers from 0 to 32, meaning, as we prove how to make number from 0 to 16, it would also prove that of 17 to 32.  Same goes for 0 to 16, 0 to 8, 0 to 4, 2 and then 1.

This assumption can be confirmed by starting the pile from any number that we wish to produce, and then sum the pennies into a single 64 pile.  Evens are easy to produce since doubling their number would also be even, and thus the operation can be proceeded for either doubling or halving the pile to make further changes.  As for odds, their doubles would also be an even number, and thus that same of the even can be said.  As long as the pile is in the even number, the procedure to halve either pile can be continued, and saying that all odds can be formed by halving the even, indicates that any number of pile of pennies can be produces in this problem.

The problem shares the nature of digitals and binary element.  As even and odd can be translated into 0 and 1 to the end, the fact that binary is able to produce any number also proves that this problem can make any number.

1 min left.  I must post this.
Hope I've explained enough so that I would make sense.
Pity that I can't add tree image to show halving processes and stuff.
Well, thanks for the term, and hope I'll see CSC next year!

Final Day

Final day at last!

But I must admit that I've been updating this SLOG only occasionally, and it got sloppier as the term approached to the end.  The assignment was quite time consuming than i originally thought, and as I compared the importance of this to other assignments that had to be done sooner, I tend to lose my motive to work on this.  Yet, this gave me with good opportunity to reflect and think about the course material, and for that I appreciate what this assignment deepened my knowledge in both quality and quantity.

DrRachet programs till today were easy to follow.   I found the commands related to the list functions, such as depth and flatten commands, were particularly difficult than other commands though.  Especially as I got to confirm this knowledge in tutorial today, I'm not confident with my answers.
As for computing history and mechanics, the establishment of internet and long range networks were particularly interesting since I use the product of it everyday and yet I didn't know such history of it.  

Wikipedia project was the most time consuming and also the most entertaining assignment that I've had so far.  I was happy to use my Japanese language to edit the details of the article, and getting to know how I'm able to edit the articles that might be seen a lot in a future gave me confidence with my work's power of publicity.

The course have been very entertaining and full of useful knowledge.  In fact I'm considering of taking advanced course for next year.  Let's see how the schedule turns out...

Week 9 : retrieving from the memory... MidTerm2

I've retrieved the information from my memory about this slog activity just after the midterm, and noticed that I was away for almost three weeks...

Since the sixth week, week after we had our first midterm, we've focused on study of computer architectures and function of its consistent such as memories.  And as always, we had our time for practicing new application of DrRacket programs. 

DrRacket part was fairly easy until week 7 where we had to decompose and reconstruct images’ color and map their colors, which our professor specifically mentioned that a lot of students found difficulties in tutorial, and so did I.  Another tutorial was spent to get a better grip of this part, and there I found myself in much better position. 

As for computer’s architecture, I was unable to attend to lecture with Von Neumann’s architecture, and for same reason I found that section of second midterm specifically difficult.  The slides from that day were indeed accessible, but I sometimes find professor’s handwriting little bit difficult to read.  I would also usually leave a note on pdf file of those slide for my own memo from lecture, and failing this made this part challenging. 

Yet, I still found myself okay in the second test, specifically on DrRacket’s section, and I hope that brought my score high enough. 

For following weeks till final exam, I would like to leave a post in here at least once every week, and try to attend every lecture. 

I’m also worried with how my Wikipedia project would turn out.  I’ve chosen pages that needs translation and cleanup, so I could use my Japanese skills, and for this type of contribution was accepted but not specified for how many pages I’m suppose to edit.  I hope I can get a reply soon for this.  

Week 6 : Midterm and Binaries

I noticed that I've forgot to update the blog last week due to a midterm tests.

We were given an access to past test, and I was preparing myself for it on thursday.  I find this course very amusing and interesting, and that interest kept me up to date with the class and I was quite confident before the test.  My only worry was to mix up the names of the famous contributors of computer science.  On the other hand, I was most confident about questions with DrRacket program, simply because it was my best interest and tutorials quizzes until today are all full mark.
And the test turned out to be very similar to last year, which made me, and I hope many others as well, easier to deal with.  Except for the last question, which I was confused with what the question was asking.  That complication lead till a very last minute, and I was not able to dash my pen on the very last question of the last page.  Overall, I found to test fine.  I hope I did well.

As for this week, I learnt about the binaries and digital system.  I was familiar with the system but the lecture was a little bit confusing when it came to a part with bitwise operators.  It took me a while after the lecture to figure out, but now I feel a lot more better with it.  Tutorial was easy as well.  I found aggregates and use of definition codes with museum very interesting, and thought for a while about their implications.  Once the lists are made and able to be processed, I assume there are more things that it can develop to, such as making particular list of numbers associated with different values represented by binaries.  Its hard to put it in words in here, but I'm interested in further work next week.

Past weeks were busy but I found them very worthy.  Since the midterm is over, I feel less stress regarding the class.  Only worry is the mark.

Week 4: Big-bang and Wiki Project

Late update... I hope one day is still acceptable without penalty or such sort...

This week's material was regarding of wikipedia project, which is separated in three parts over our semester, and about animating images with DrRacket.

This week's part for wikipedia project was relatively easy considering was is ahead of us.  Registration and submitting the pages I may edit was the task, and it finished in no time.  I consider following two kinds of editing in general: placing an image, and clean up after the translation.  Image finding seemed easy; only need time to find (or make) an image for the page.  As for a translation clean-up, I thought I could use my Japanese and edit pages such as University of Tokyo.  I'm more interested in translation clean-up.

The lecture in class was focusing on how to use command big-bang, which animates the image that is applied into the function.  I learned its capability with how I'm able to edit the frequency of frames in the animation, and what kind of animation I'm able to make, such as rotating (like a clock work) and flipping images in whichever 2D dimension.  I found it fascinating and I'm looking forward for what else the function is capable of.

My worry at this moment is the coming term test on Thursday.  I'm sure that I'm up to date with the lecture and tutorials, but I guess it is natural to be anxious of my performance to prove my required knowledge.  I only have one other test on tuesday for sociology, and aside from that I should be able to find enough time to go through the lecture slides to prepare myself.

Tony

Week 3: DrRacket Definitions

This week's material focused on to learn how to let DrRacket memorize the definitions that we ought to reference later on, by programing the definition of what we mean by certain values.  This involved how to play with images with picturing-programs, mostly on defining a set of sequences which creates expected outcome (rosette program).

The material seemed intimidating and overwhelming at the beginning, but it turned out better as the lecture proceeded.  Defining a set was understandable once the model is unfolded (as it is done on the videos online), and I found myself picking up faster than I expected.

My worry for now is that I'm not so sure yet with what the last video about definitions was dealing with.  Since I've ran out of time by the end of tutorial, I wasn't able to finish watching this video.  On top of that, I was still unable to finish copying what the third video was doing with rosette program.  I noticed that the difference in my program with what is on the video was the different images, but I saw no other difference, and TA was struggling to find it as well (unfortunately, the time ran out before he fully explained the program).  So, perhaps I should go over this part by next week.

And by the way, I didn't mistake my tutorial room this time.  The quiz from last week turned out to be full mark, so I would like to keep up with the material as much as I could, starting from reviewing this week's material.

Hope next week would be more successful than this one.

Tony

Week 2: DrRacket / Values

This would be a first week to leave a note of my progress in CSC104, and this week I learned about how to play with values in DrRacket program.

Concept was to express, transform, combine and decompose values (we used digital images this time) in DrRacket, and by professor's lectures and with his demonstrative online videos, I think I am confidant with the basics use of it.
I was rather worried about my performance since I had no knowledge ahead, and the class is very different than other ones that I'm currently enrolled.  I realize that this is the fundamental for coming knowledge, yet it did help me with my motivation.  I find the course inspiring since I always enjoyed getting to know what I'm capable of doing on computers.

This week was also a first week that I went to tutorial, and I found myself in a wrong room with many others. I hope that wont happen next week.  Also, next week, if I could, I would try to keep myself more awake in the lectures, since I found myself little bit dizzy in a mornings.  Now that many of my concerns regarding of courses are resolving, I should be able to manage myself to be more present in lectures.

There is no concern about this class that I have right now.  If I were to be critical, I wish tutorial rooms were announced clearer.

Well, with that I should leave for this week.  I hope my online journal satisfies the course's expectation.

Tony