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# Help with maths...snif,sniff

fred fredricks
Greenhorn
Posts: 16
hello!!!
ok, i have to do a maths problem sheet...and i am stuck...can u guys help me out?
thanks!!
e) give the outline of an efficient algorithm to test if a point is inside a rectangle.
f) how would you test whether two circles intersect
thanks!!!

Jason Menard
Sheriff
Posts: 6450
Moving to Programming Diversions. Post followups there.

Bhau Mhatre
Ranch Hand
Posts: 199
Originally posted by mike brindley:
f) how would you test whether two circles intersect

One way is to test if the distance between their centers is less than the sum of their radii.

HS Thomas
Ranch Hand
Posts: 3404

give the outline of an efficient algorithm to test if a point is inside a rectangle.

Given the point's co-ordinates x,y
If (x >= Xa) and (x <= Xb)
and if (y >= Ya) and (y <= Yb) then point x,y is inside the rectangle,
where the co-ordinates of the four points are Xa,Ya ; Xa,Yb ; Xb,Ya ; Xb,Yb.
Or , more concisely
Xa <= x >= Xb and Ya <= y >= Yb
I think that works ,as long as you are given the points and rectangles co-ordinates.
[ August 25, 2003: Message edited by: HS Thomas ]

Mark Herschberg
Sheriff
Posts: 6037
This sounds a lot like homework problems to me.
--Mark

fred fredricks
Greenhorn
Posts: 16
yeah its homework...i have done like 15 questions, i only have a few left...
ie, the ones i just couldnt figure out how to do, thats why i ask for help....
its ok right?
thanks...

Mark Herschberg
Sheriff
Posts: 6037
Some people try to get homework problems done for them by posting on this site. You were upfront about it.
I just wanted to make it clear to other posters that they shouldn't solve the problems outright, but rather give you advice and suggestions. I think that is fine.
I'm not sure if this is quite the right forum for it, in that this forum is for problem discussion, and we would have to minimize discussion in order to not do your work for you.
--Mark