Co-ordinate system disaster

shreyas_potnis

17th June 2003 08:57 UTC

Co-ordinate system disaster
ah....:( A very unhappy day today. It just happened that we had a 25 marks test the day before yesterday on graph.
The test was very easy, although I made a very grave mistake. I am so used to the inverted y-axis in AVS that I took the same thing on my graph paper, for all the problems and ended up drawing everything inverted :cry:
Hardly managed to score 8 marks because of the writing part :o

ONE OF THE REASONS WHY I DONT LIKE AVS.

sidd

17th June 2003 09:25 UTC

lol. shreyas you great gooof

Deamon

17th June 2003 09:25 UTC

That sucks. Can you still make the year? It makes you wondering why the Nullsoft guys inverted the Y-axis instead of using a normal one.

Magic.X

17th June 2003 09:32 UTC

Because they wanted to confuse shreyas. :blah:

LMAO!

Sorry man, but this is just too funny!

Tuggummi

17th June 2003 09:58 UTC

When it fucks up your school, you know you've had too much avs :p Remember what happened to fsk? :igor:

[Ishan]

17th June 2003 10:25 UTC

Sorry to increase your pains shreyas but i noticed this bug in your DCS ape(i dont know whether anyone has found it or not), it does not return random colours i,e. if you use two DCS they both return same colours!
Here's where i found the bug:

Magic.X

17th June 2003 10:42 UTC

LOL!

This is a commonly known bug. The random function works by predefined permutation, so its only pseudo random. If you dont initialize the start value, it will always return the same order.

[Ishan]

17th June 2003 11:00 UTC

sorry but this was first time i saw this, i never had this problem in DM's or SSC's tho.

Magic.X

17th June 2003 11:15 UTC

No, you got me wrong. I meant its a commonly known programming fault that many peopel make.

You wont have this prob with DM's or SSC's as they dont have this fault.

What you need to do is randomize (get a start value from the system timer)

Phaze1987

17th June 2003 13:04 UTC

o_O !!! "An indian boy`s life is fucked up because of a thing called AVS"

Magic.X

17th June 2003 13:43 UTC

I think he'll recover from this soon. Head up Shreyas, there's more important stuff in life than tests @ school.

[Ishan]

17th June 2003 13:51 UTC

Shreyas this test was at school???:igor: Are'nt your summer holidays going on?

Tuggummi

17th June 2003 14:02 UTC

Ishan, not everyone goes to a school that is like most highschools... You see me posting? That means im still at school... You won't see me posting next week though.

Magic.X

17th June 2003 14:08 UTC

Dunno 'bout India, but here in Germany, the start and end of vacation is diffrent for every state.

This is done to avoid traffic jams on the highways.

Guess it should be the same in India.

Where in India do both of you live?

UnConeD

17th June 2003 14:29 UTC

Shreyas: As long as you pick two non-linear dependant base vectors you have a 2D coordinate system.
How to orient the X,Y axes is purely arbitrary. Of course you will almost always pick an orthonormal system (which you still did). In 3D, the most common rule is the right-hand rule, but in 2D you usually pick whichever is easiest.

On my mechanics exam yesterday I picked a 2D coordinate system with the X,Y axes at 30° and 60° angles to the paper. Basically it was about a prism lying flat on the ground like this. On the sloped side on the left was a box, and the right a cylinder and both were connected with a rope over the top. The point was to calculate the speed of the three parts (box, prism and cylinder) given all the masses, friction coefficients, etc. I put my X,Y axes like this:


(. = rope, [] = box, O = cylinder, * = pulley)
   .*.
 . _-__.                   _-__  X
[]-    --O             Y _-    --__
-        ¯¯--           v          >
¯¯¯¯¯¯¯¯¯¯¯¯¯
(ph33r teh ASCIII ATR!!!11!!)

Makes the assignment easier because the two objects on the slopes then move in either the X or Y direction rather than an odd angle.

I don't see why you'd lose so many points for that though. What are your teachers taking? If the actual contents of the graphs were right, it doesn't matter.
In fact, they're teaching math wrong. Math is nothing more than a set of chosen conventions, that are elaborately built upon. Some of these conventions are used to make things easier (e.g. putting your x,y axes at 90° angles and using the same scale on both) but some are purely arbitrary (e.g. which way the axes point, left-handed or right-handed). By taking away points for this they're showing they don't care about whether or not you understand math, but simply if you can reproduce the stupid graphs exactly the way they want you to reproduce them.

(PS: right hand rule... extend your right hand so it's flat. Your thumb is the X axis, your fingers the Y. Now bend your fingers towards you so they are at 90° with your hand. They now point in the right-handed Z direction.)

Magic.X

17th June 2003 14:55 UTC

ok, you're generally right UnConeD, but you have to differ between geometrical drawings and math graphs that shall show sin, cosine, etc.

I don't know any teacher that would give points on a "custom" coordinate system.

shreyas_potnis

18th June 2003 16:17 UTC

Ok, guys, here's the deal:
The education system in India is really fucked up.(atleast I think so).
This test wasnt in the school but in the tution classes. I was unhappy because if you dont score well, you wont get in Intensive Coaching, a special course to train the potential merit list holders.
And I was talking about the education system in India. I hate it. Firstly, you have to take all the subjects till 10th std. Then the competition is so intense that even 1/2 mark counts. The papers are corrected by the board (in X std) and the rules are sort of weird.

I argued with the teacher a bit, but what she told was true. She told the "I can give you makrs now, but then the board examiners wont. If it werent for the inverted y-axis, you could have scored 25/25"

And UnconeD, you are right, what they see if whether you can reproduce the stupid graphs exactly the way they want you to reproduce them.

Magic: I live in Thane, a city very close to Mumbai, Maharashtra and Ishan lives in Jabalpur, Madhya Pradesh. And no, the vacations start and end at almost the same time. hey are based on 1) the summer vacations - because of the intense heat. 2) Diwali, major festival of the hindus 3) Christmas - Not all schools have vacations, but we have for 12 days.

Ishan: this test was in the tutions and the school has already started :)

[Ishan]

18th June 2003 17:37 UTC

Started?:eek: so soon! the temp. is like 45 centigrades here!!! My schools are going to start from 1st July:)

shreyas_potnis

19th June 2003 16:35 UTC

still that hot! Yeah, because you live in the central side, it raining heavy here :)

Magic.X

20th June 2003 08:24 UTC

A friend of mine recently visited GOA / India and some other places. Nice party culture there although it has become very technoid within the last years.
Anyway, its exactly what we try to rebuild on a local basis here. :D

shreyas_potnis

20th June 2003 09:34 UTC

chk this out!
GOA Beach

Magic.X

20th June 2003 10:47 UTC

Hehe, nice! :D

Only am i missing some palms and dancing peopel right under em.

Something like this:

http://home.pages.at/ptcle/Partyfoto...Stage%2001.JPG
http://home.pages.at/ptcle/Partyfoto...floor%2001.JPG
http://home.pages.at/ptcle/Partyfoto...floor%2003.JPG
http://home.pages.at/ptcle/Partyfoto...floor%2005.JPG
http://home.pages.at/ptcle/Partyfoto...Night%2001.JPG
http://home.pages.at/ptcle/Partyfoto...Night%2005.JPG

[Ishan]

20th June 2003 17:36 UTC

still very hot here:( anyway nice preset shreyas:up:

shreyas_potnis

21st June 2003 15:55 UTC

I was supposed to release this with the next pack, bu the temptation was too strong.

[Ishan]

23rd June 2003 07:13 UTC

but still looks kinda empty...