For some reason, my physical wellness behaves just like biorhythms, guess today I hit a record low, I'm very tired lately... just couldn't get enough quality sleep...
Today's lecture I didn't even bother copying it down or do the brainstorming excercise, that's how bad it was, but I still remembered Danny lectured about a more complicated case of an iterative loop.
Ack! Because of that I don't think I did well on the 207 midterms either, but what can I do?
Guess I'll have to sleep earlier today.
Wednesday, October 29, 2008
Monday, October 27, 2008
A long entry
Ahh... a lot of things to write about:
First, the deadline for problem set 4 got extended until today (originally due on Fridays), being lazy as I'm usual was, I practically delayed doing it until Sunday, it wasn't that hard, just have a lot of explanation to do.
Second, assignment 2 was also due today (in the midst of me writing this...), I have to say those problems are extremely challenging (I have to thank whoever made this, as this assignment gave huge amounts of exercise to my brain). Strange note here, bonus marks? Oh well... I don't think I have enough stamina or brain power to do it after the horrors on that first question.
As for today's lecture, we started doing program correctness for iterative (as compared to recursive) programs. Like Danny noted, it really does get awhile to become comfortable doing such proofs as the program is longer and less straightforward compared to the recursive ones. Not only that, the fact that it is necessary to prove that the loop terminates threw me off, other than that it looks extremely similar to how you'd prove for a recursive program's correctness.
The prove of correctness, as I've observed, requires the student to have excellent and clear writing skills, which I lack both (which will undoubtedly gave me a disadvantage). Guess finding time to practice is my only hope...
First, the deadline for problem set 4 got extended until today (originally due on Fridays), being lazy as I'm usual was, I practically delayed doing it until Sunday, it wasn't that hard, just have a lot of explanation to do.
Second, assignment 2 was also due today (in the midst of me writing this...), I have to say those problems are extremely challenging (I have to thank whoever made this, as this assignment gave huge amounts of exercise to my brain). Strange note here, bonus marks? Oh well... I don't think I have enough stamina or brain power to do it after the horrors on that first question.
As for today's lecture, we started doing program correctness for iterative (as compared to recursive) programs. Like Danny noted, it really does get awhile to become comfortable doing such proofs as the program is longer and less straightforward compared to the recursive ones. Not only that, the fact that it is necessary to prove that the loop terminates threw me off, other than that it looks extremely similar to how you'd prove for a recursive program's correctness.
The prove of correctness, as I've observed, requires the student to have excellent and clear writing skills, which I lack both (which will undoubtedly gave me a disadvantage). Guess finding time to practice is my only hope...
Saturday, October 25, 2008
End of the seventh week
Date: Friday
Oh my, guess I'll never been free again until the end of school year - with midterms gone, assignments/problem sets of various kinds resume again.
We finished writing out the program correctness for the greatest common divisor, as well as starting on the divide-and-conquer (theory or algorithm?) for natural powers. As I've been through 2 midterms and lack of sleep throughout the whole week, it's natural for me to collapse (fall asleep) during the middle of the lecture, don't worry... I still picked up the lecture while resting~
Since the fourth problem set gets postponed, my natural inclination tells myself to put it off till the weekend. With both the second assignment and problem set due on Monday (at different times of course), it's very hard to decide which one to focus on.
Either way, I'm done writing here, got to go working on the assignments and problem sets.
Oh my, guess I'll never been free again until the end of school year - with midterms gone, assignments/problem sets of various kinds resume again.
We finished writing out the program correctness for the greatest common divisor, as well as starting on the divide-and-conquer (theory or algorithm?) for natural powers. As I've been through 2 midterms and lack of sleep throughout the whole week, it's natural for me to collapse (fall asleep) during the middle of the lecture, don't worry... I still picked up the lecture while resting~
Since the fourth problem set gets postponed, my natural inclination tells myself to put it off till the weekend. With both the second assignment and problem set due on Monday (at different times of course), it's very hard to decide which one to focus on.
Either way, I'm done writing here, got to go working on the assignments and problem sets.
Wednesday, October 22, 2008
GCD
...This sure is a busy week...
We finished off proving the program correctness for the binary search function, I have to say it was long: it took off one side of a blank line paper! I can never do anything like that requiring to write so much. As well, we got started on the greatest common divisor (GCD) that has been delayed for some time.
Ack! Two midterms in one week, I really couldn't concentrate on today's lecture as my mind is split between studying and working on the assignment, oh well... time to end it here then.
We finished off proving the program correctness for the binary search function, I have to say it was long: it took off one side of a blank line paper! I can never do anything like that requiring to write so much. As well, we got started on the greatest common divisor (GCD) that has been delayed for some time.
Ack! Two midterms in one week, I really couldn't concentrate on today's lecture as my mind is split between studying and working on the assignment, oh well... time to end it here then.
Tuesday, October 21, 2008
Guest lecturer
Date: Meant to post it yesterday, but I'm just too tired and I forgot...
On Monday Danny was away to UTM doing some... fictitious research? Either way we have a special lecturer from UTSC, named Nick, to start on proving the correctness of your program.
It's something not that hard I guess, having seen precondition/postcondition everywhere when coding programs, yet I find it intriguing to prove how a program is correct.
It was... overall extremely interesting, Nick was a wonderful lecturer despite not many people shown up to this class (I assume they are away studying for the stat midterm, which is a killer). Wish we could have him again (or someone else) someday.
On Monday Danny was away to UTM doing some... fictitious research? Either way we have a special lecturer from UTSC, named Nick, to start on proving the correctness of your program.
It's something not that hard I guess, having seen precondition/postcondition everywhere when coding programs, yet I find it intriguing to prove how a program is correct.
It was... overall extremely interesting, Nick was a wonderful lecturer despite not many people shown up to this class (I assume they are away studying for the stat midterm, which is a killer). Wish we could have him again (or someone else) someday.
Saturday, October 18, 2008
First test results
Date: Friday
I'm always pessimistic about tests, but always ended up getting higher then hoped for. This is a good thing to lower your expectation in U of T slightly as you feel better when you are not looking too high up at what you are expecting, but still I need to improve as I think the TAs really gave us easy marks on this test.
As well, we handed the third problem set in. I'm a bit worried about what I conjectured because there has been a little bit of confusion with the term "closed formula", I ended up deriving a sum notation which on the discussion board is obviously incorrect, I really hope I didn't mess up on that.
Anyhow, we officially moved away from induction to time complexity proofs, which, I hope, is less abstract than the multiple flavours of induction.
...Kind of forgetting what I learned on Friday, because I'm spending time right now doing rough works for the second assignment, I have to say those questions are really interesting, especially the ternary trees one.
I'm always pessimistic about tests, but always ended up getting higher then hoped for. This is a good thing to lower your expectation in U of T slightly as you feel better when you are not looking too high up at what you are expecting, but still I need to improve as I think the TAs really gave us easy marks on this test.
As well, we handed the third problem set in. I'm a bit worried about what I conjectured because there has been a little bit of confusion with the term "closed formula", I ended up deriving a sum notation which on the discussion board is obviously incorrect, I really hope I didn't mess up on that.
Anyhow, we officially moved away from induction to time complexity proofs, which, I hope, is less abstract than the multiple flavours of induction.
...Kind of forgetting what I learned on Friday, because I'm spending time right now doing rough works for the second assignment, I have to say those questions are really interesting, especially the ternary trees one.
Wednesday, October 15, 2008
Refreshed
Certainly, after a long weekend of productivity, I managed to get some rest and caught up with all my courses, what a relief.
I felt different too, even though I'm physically tired, I still am able to concentrate on the lecture today mentally and perform above-average on the brainstorming session. I'm in a much better state compared to before, when I'm exhausted both mentally and physically.
We carried on with more recursion "unwinding" practice and proving the closed form formula... nothing new here, so I'll end my entry now, got to go study another midterm in this "Fantastic" month.
I felt different too, even though I'm physically tired, I still am able to concentrate on the lecture today mentally and perform above-average on the brainstorming session. I'm in a much better state compared to before, when I'm exhausted both mentally and physically.
We carried on with more recursion "unwinding" practice and proving the closed form formula... nothing new here, so I'll end my entry now, got to go study another midterm in this "Fantastic" month.
Saturday, October 11, 2008
Reflections on the first midterm
Date: Late by one day
It's always usual to do bad on your first attempt, it is also true that people can improve from it after their first mistakes.
I don't think I did well on the first midterm, I still managed to finish all the proofs but I doubt I'll get full marks on any one of them. The first page of the midterm specifically said not to mislead the marker, but I ignored the warning and write something that looks very ambiguous and then quickly joined up the induction step to the conclusion since I'm running out of time (I started the writing part after half the midterm time had passed).
It can be attributed to the lack of practice writing proofs, as well as the lack of preparation on this midterm (how surprised I was when I looked at the question - note to self: never underestimate this course again). Luckily whatever mark I got from the midterm can be canceled out by the extremely lucky high mark obtained on the assignment.
A mistake is a mistake, the only thing I wish I could do is to learn from it and do better next time!
It's always usual to do bad on your first attempt, it is also true that people can improve from it after their first mistakes.
I don't think I did well on the first midterm, I still managed to finish all the proofs but I doubt I'll get full marks on any one of them. The first page of the midterm specifically said not to mislead the marker, but I ignored the warning and write something that looks very ambiguous and then quickly joined up the induction step to the conclusion since I'm running out of time (I started the writing part after half the midterm time had passed).
It can be attributed to the lack of practice writing proofs, as well as the lack of preparation on this midterm (how surprised I was when I looked at the question - note to self: never underestimate this course again). Luckily whatever mark I got from the midterm can be canceled out by the extremely lucky high mark obtained on the assignment.
A mistake is a mistake, the only thing I wish I could do is to learn from it and do better next time!
Wednesday, October 8, 2008
Quick entry
Not going to write much here as I have Linear Algebra quiz and this course's midterm on Friday: we finished up proving using structural induction on the number of nodes in a binary tree, and started to prove the matching parenthesis claim.
The claim itself is a bit weird (haven't seen a proof like this), along with the fact that I am always tired in the morning that affects my thinking (so I didn't even bother trying out the proof for it but just plainly write the initial solution down).
Don't really want to waste time here, as I'm behind in reading for both MAT223 and this course, got to get as much as I can done before the test starts.
The claim itself is a bit weird (haven't seen a proof like this), along with the fact that I am always tired in the morning that affects my thinking (so I didn't even bother trying out the proof for it but just plainly write the initial solution down).
Don't really want to waste time here, as I'm behind in reading for both MAT223 and this course, got to get as much as I can done before the test starts.
Monday, October 6, 2008
Just need that much more time...
Just like I'm always late for Friday entries, I'm always tired when it is Monday (perhaps due to the cause of weekend?).
This week we learned about finding the closed form for the Fibonacci sequence, as well as trying out a similar sequence just like the Fibonacci number. As my brain is not functioning as much as I wanted, I did what I can by following the example on the slide and managed (surprisingly) to work out half the solution to the closed form for the sequence.
Not only that, we also started learning to define sets with induction for trees, let's just say that everything about this part of the lecture just flies through my brain, how I hate Mondays...
Back to midterm preparations, just need as much time as I can put it in... as well as a decent sleep (at least) before the dreaded week begins and as well as to get more sleep the day before the midterm.
This week we learned about finding the closed form for the Fibonacci sequence, as well as trying out a similar sequence just like the Fibonacci number. As my brain is not functioning as much as I wanted, I did what I can by following the example on the slide and managed (surprisingly) to work out half the solution to the closed form for the sequence.
Not only that, we also started learning to define sets with induction for trees, let's just say that everything about this part of the lecture just flies through my brain, how I hate Mondays...
Back to midterm preparations, just need as much time as I can put it in... as well as a decent sleep (at least) before the dreaded week begins and as well as to get more sleep the day before the midterm.
Saturday, October 4, 2008
The "always late by one day" Friday entry
Date: Yesterday
Guess I'm always late for Friday entries, since I find it so tempting to just relax it away...
Today's class we looked at the binary search function and tries to unwind it's patterns as well as analyzing its running time. With most of the stuff coming back from CSC165, I find it not that hard at all even though my brain is half-dead from waking up extremely early today.
There's... a bit of break from all the assignments and problem sets this week, since the midterm is next week for this course (unfortunately there's still the STA 247 homework). I won't write too much here then... I will use this time wisely (I hope, I'm a huge procrastinator...) to catch up on my other courses as well as preparing for the midterm-filled October.
Guess I'm always late for Friday entries, since I find it so tempting to just relax it away...
Today's class we looked at the binary search function and tries to unwind it's patterns as well as analyzing its running time. With most of the stuff coming back from CSC165, I find it not that hard at all even though my brain is half-dead from waking up extremely early today.
There's... a bit of break from all the assignments and problem sets this week, since the midterm is next week for this course (unfortunately there's still the STA 247 homework). I won't write too much here then... I will use this time wisely (I hope, I'm a huge procrastinator...) to catch up on my other courses as well as preparing for the midterm-filled October.
Wednesday, October 1, 2008
October!
It is October already, that was fast!
We continued on with induction for the Fibonacci numbers, where we shrunk the base cases from 2 to 1 (we really just need n=0 to make the prove work).
Then we moved onto Python recursion program, zero-pair binary strings, which looked extremely similar to the link I've found from the last post, we did some algorithm analysis in which we learned back in CSC236.
We also take a quick look at recursion functions that are not very well-defined, in fact, the third function surprises me a lot - it was quite hard to grasp the concept right after the lecture, but after working out the algebra I felt a bit relieved to see that it actually can work.
Off-topic tidbit: We actually went through the overheating "time-out" of the projector (that happened since last week) and got it working again. I really wonder what's going on with the projector (why didn't it happen before?) and why the maintenance people did not fix it yet. Also, somehow the lecture room (compared to my other lecture classes) is quite... humid, is it because of the small room and huge amount of people? That I will never know...
We continued on with induction for the Fibonacci numbers, where we shrunk the base cases from 2 to 1 (we really just need n=0 to make the prove work).
Then we moved onto Python recursion program, zero-pair binary strings, which looked extremely similar to the link I've found from the last post, we did some algorithm analysis in which we learned back in CSC236.
We also take a quick look at recursion functions that are not very well-defined, in fact, the third function surprises me a lot - it was quite hard to grasp the concept right after the lecture, but after working out the algebra I felt a bit relieved to see that it actually can work.
Off-topic tidbit: We actually went through the overheating "time-out" of the projector (that happened since last week) and got it working again. I really wonder what's going on with the projector (why didn't it happen before?) and why the maintenance people did not fix it yet. Also, somehow the lecture room (compared to my other lecture classes) is quite... humid, is it because of the small room and huge amount of people? That I will never know...