Circle question, have centre point and radius, need points on the circle...

apeking

Just say the i have a circle,

Centre of circle is (5,5),

Radius is 12,

What i want is the co-ordinates of the edge of the circle,

i know this is easy LC maths but i cant remeb how to do it and i have no maths book!

Thanks all

Irish Wolf

apeking wrote:

Just say the i have a circle,

Centre of circle is (5,5),

Radius is 12,

What i want is the co-ordinates of the edge of the circle,

i know this is easy LC maths but i cant remeb how to do it and i have no maths book!

Thanks all

Just add/substrate the radius from your x or y centre point value for some of the infinite points on the circle...

e.g. (5,17) (17,5) (5,-7) (-7,5) are all points along the circle.

The standard form of the equation for a circle is (x-h)^2+(y-k)^2=r^2

h,k are the circle centre points and r is the radius... so for the circle you described above the equation would be (x-5)^2+(y-5)^2=144

apeking

Irish Wolf wrote:

Just add/substrate the radius from your x or y centre point value for some of the infinite points on the circle...

e.g. (5,17) (17,5) (5,-7) (-7,5) are all points along the circle.

The standard form of the equation for a circle is (x-h)^2+(y-k)^2=r^2

h,k are the circle centre points and r is the radius... so for the circle you described above the equation would be (x-5)^2+(y-5)^2=144

Ye thats good if you want to get the co-ordinates at 0, 90, 180 and 270 degrees, what about the angles in between them, like 2 degrees for example??

Irish Wolf

apeking wrote:

Ye thats good if you want to get the co-ordinates at 0, 90, 180 and 270 degrees, what about the angles in between them, like 2 degrees for example??

x(t)=r.cos(t)+h
y(t)=r.sin(t)+k

apeking

Irish Wolf wrote:

x(t)=r.cos(t)+h
y(t)=r.sin(t)+k

Thank you, that is great.

Much appreciated