Check which side of a plane points are on

Question

I\'m trying to take an array of 3D points and a plane and divide the points up into 2 arrays based on which side of the plane they are on. Before I get to heavily into debug

Answer 1

Following the 'put points into the plane's equation and check the sign' approach given previously. The equation can be easily obtained using SymPy. I used it to find location of points (saved as numpy arrays) in a list of points.

from sympy import Point3D, Plane
plane=Plane(Point3D(point1), Point3D(point2), Point3D(point3))
for point in pointList:
        if plane.equation(x=point[0], y=point[1],z=point[2]) > 0:
            print "point is on side A"
        else:
            print "point is on side B"

I haven't tested its speed compared to other methods mentioned above but is definitely the easiest method.