How to find centroid or center of a 3D irregular shape

I would like find the centroid or center of a 3D irregular shape from its data set of x,y,z coordinates. How do i go about it?

Answer 1

[Star Strider]

The centroid is defined as the arithmetic mean of the points, so just do that in each (x,y,z) dimension.

[Conrade Muyambo]

Okay perfect. Just like x1=mean(x), y1=mean(y), z1 = mean(z) where x,y and z are my coordinates vectors

[Star Strider]

Yes. The ‘x1’, ‘y1’, and ‘z1’ are the coordinates of the centroid.

[Arto]

I think this is not the correct answer if the xyz coords. describe the vertices of the irregular 3D shape.

Use polygonCentroid3d in stead.

[Joseph Olson]

I agree with Arto. The mean is not appropriate to use if the points defining the object are not uniformly sampled and distributed such that the mean will be the same as the centroid. Think of a cube-ish shape where there are many points/vertices on one face but very few on the opposite face. The mean will give a value biased towards the dense face.