Dynamic VPython-based visualization of a vector

vector.py

import random
import visual

MAXDIFF = 0.05

class ArrowCoords(object):
    x = random.random()
    y = random.random()
    z = random.random()
    def get(self):
        self.x    += -MAXDIFF/2+MAXDIFF*random.random()
        self.y    += -MAXDIFF/2+MAXDIFF*random.random()
        self.z    += -MAXDIFF/2+MAXDIFF*random.random()
        return (self.x,self.y,self.z)

#============================ main ============================================

def main():

    coords = ArrowCoords()
    
    arr = visual.arrow(
        pos       = (0,0,0),
        color     = visual.color.green,
        material  = visual.materials.emissive,
    )

    while True:
        visual.rate(100)
        arr.axis  = coords.get()

if __name__=='__main__':
    main()