How do you calculate moment of inertia for circle?

[Josh The Cool]

Hey, not sure if this is the right place to post this, but here it goes. how do you calculate the moment of inertia for a circle that is not at its center of gravity. I am trying to find the moment of inertia for a complex shape made of many circles, and this seems like a good place to start. Forgive me if the answer is simple, because I have spent hours googling this question and have come up empty handed. I would greatly appreciate any help!

 

[mfb]

Around which axis? In general, with an integral, but sometimes there are some tricks to avoid this, like the parallel axis theorem.

 

[Josh The Cool]

This is in two dimensional space. So I think the z axis if I understand correctly.
Edit:
I also looked at that wiki page, but couldn't apply it in any useful way.

 

[mfb]

What is unclear about the Wikipedia page?

 

[Dr.D]

Are you thinking of a reference point in the plane of the circle but not at the center of the circle?

A circle is a purely geometric figure, and as such, has no cg. It does have centroid; is that what you have in mind?