1. ## Test yourself

this is not for math gods! just for beginners in game math like myself!

if you answer them ok you have enough to get you through basic game programming math .other wise you gote start reading more books on math that u learned and forgot while ago,like i do.

1-is vector addition comutative or associative?

2- is this statment correct:

vector displacement "v"
vector displacement "u"

is lenght |v + u| == lenght |v| + lenght |u|

is it smaller < or bigger>

T T
(42, -12) + (8, 24) == ?

4-adding a vector object "v" to point object "p" will result to:

a: vector object x.
b: point object x.

well thats all for now i will give out the answer little bit later.

2. This wouldne be homework now would it?

3. Originally posted by Fordy
This wouldne be homework now would it?
Then you would have to admit it's an original approach

4. c'mon, the guy is TESTING us, show some appreciation

5. well....... its a bit later, i think we all failed (miserably) what are the answers

6. *No im too old for homeworks.

Ok my cothreaders here is a few more and little bit later i will put the answers up here.

5-How many vectors do you need to construct a plane?

a-1
b-2
c-3
d-4

6-what is the lenght of the column matrice(0, 0) T :

a-1
b-0

7-can the lenght of a vector be negative?

8-if the lenght of v(3, 4)T is 5.

what is the lenght of s(-3, -4) T ?

9-if we have column matrice vector.

does its lenght change if we change the coordinate frame:

a- yes
b- no
c-depends

10 the final- what is the transpose of
|3|
|4|

---------------------------------------------------------------------------
i hope this thread makes some of you go back to your books tonight.

NO MORE TV FOR YOU! AHA

7. >*No im too old for homeworks.

>here is a few more

forget math, you need to go back to grammar school...

and please, dont think that the people on a board with such strict rules against giving out homework answers will fall for such a transparent ploy to get answers. i think the people here already know 'what it takes' to be a game programmer, and we dont have to take random quizzes that look suspiciously like those dreamed up by a teacher to find that out.

we all know that you are just trying to tempt people into answering your questions for you, so just admit that youve been caught and move on...

8. ok, ill bite....

the answers to questions 1 through 10 are:

purple.

...... [ ahh good ol' linear algebra, one of my favorite classes last year ] .......

btw: if you cant do your homework on your own, how do you expect to work for blizzard/bio-ware/EA/<insert cool game dev. here> .... the easy way out is not always the best way.

9. -->forget math, you need to go back to grammar school...

if u pay the tuition i will.

-->and please, dont think that the people on a board with such strict rules against giving out homework .

Well ... ive been on this sight since 2000 .ive seen many come many go like sunlight jp &&&&& and i know the rule of not asking for some one else to do your job for you ".look at the number of my threads". thx for bringing it up to my attention with no extra chg.

-->i think the people here already know 'what it takes' to be a game programmer,

I dont.

Did the ppl elect u to be their spokesperson ?

if all knew what it takes to be a game programmer then we wouldnt be asking so many questions on a daily basis would we?
including myself.

-->we dont have to take random quizzes

some may know what it takes, like silvercode or travis or wizzard or adrian and fordy but not "U", i havent checked your credentials yet ,,so please dont say WE.

and please next time dont try to spoil the fun and process of my
self educating effort and dont be a judge and prosecutor at once.

10. -->this is not for math gods! just for beginners in game math like myself!<--

and for the rest of you curious minds here are the correct anwers.

1- Both.

2- No , Because the lenght of the unified sum of 2 vectors is always smaller or the same as the sum of the lenghts of vector "v" and vector"u".

3-(50, 12)

4- adding a vector object to a point object ,will always lead to creation of a new point object.

5- 2 vectors.

6- the answer is == 0

7-no.the lenght of a vector is always positive.

8- sqr(-3 * -3 + -4 * -4) == 5 which proves that lenght is always
positive(unlike some folks).

9-No. just like the fixed size of your finger which can be pointed on any orientation or in any direction be it in your nose vertical or your ears horizontal ,

10-(3, 4)T

there should be a new section on this sight under:

"game programming math for dummies"

just so the threads dont crap the style of the self
proclaimed ELITE.

as silvercode says it best:

e·lit·ism or é·lit·ism

I HATE ELITISM!

11. ## ~

I'd think a vector and a point object would be very similiar, considering a vector is basically a point.

Don't you need 3 vectors to create a plane?

12. thank you for reminding me ,to note that all these are in 2D graphic. not 3D.

edit;

yes, and
no, because the resulting object wil have no lenght and no direction like a vector due to the attributes of one of the elements (point) in the prior calculation.

point is just a location in space unlike vectors, with no orientation or lenght. and as i said these are all in 2D which might be slightly at times different to 3D descriptions.

cheers!

13. I'd think a vector and a point object would be very similiar, considering a vector is basically a point.
a vector in the most abstract sense is a quantity made up of components called scalars (I assume that because although the actual values of components can change as is true with 3d math vectors their proportions will remain the same, retaining the same scale?) and the term vector has many uses outside of math/physics. Points can be appropriately represented by vectors because a point is a quantity made up of different scalars, but a point isn't a mathematical vector because a point represents a location in space whereas a vector in math represents direction and magnitude but specifically not location(am I right about the location part? I'm not sure because I know you can displace vectors which technically moves them, hmm). Vectors are used to describe heaps of data being operated on in parallel computing (each byte would be a scalar), there is a vector class in the C++ STL which holds scalars of some datatype. I just wanted to say that because I've always wondered why vectors are used to represent points, and as you see it's perfectly acceptable to have a vector class with an arbitrary usage.

14. ## Re: ~

Originally posted by rmullen3
I'd think a vector and a point object would be very similiar, considering a vector is basically a point.
I oughta club you and eat your bones!!! Don't ever say that in my presence ever again! They are extremely different concepts!

Originally posted by rmullen3
Don't you need 3 vectors to create a plane?
Nope, only 2.

15. a point and a terminal vector (the ones in math and physics) are completely different, but a point and a vector (the vector that is the abstract idea of a quantity with a bunch of components) are the same because a point, no matter what basis you are in, is still a quantity which is made up of components. right? That's the only way to explain why vectors are used to represent points so much. oh well I'm not arguing over this too much but i think im right. I haven't seen anyone develop a point class: they just use vector.

EDIT: a plane specifically means 2 dimensions, but what is the word that specifically means 3 dimensions? cube? lol