from __future__ import division                 ## treat integers as real numbers in division
from visual import *
from visual.graph import *
scene.width=600
scene.height = 760

## constants and data
g = 9.8
mball = 1   ## change this to the measured mass of the yellow sinker
L0 = 1      ## change this to the relaxed length of your spring 
ks = 1      ## change this to the spring constant you measured
deltat = 1  ## change this to be about 1/1000 of your measured period

t = 0       ## start counting time at zero

## objects
ceiling = box(pos=(0,0,0), size = (0.2, 0.01, 0.2))         ## origin is at ceiling
ball = sphere(pos=(0,-L0,0), radius=0.025, color=color.yellow) ## note: spring initially compressed
spring = helix(pos=ceiling.pos, color=color.orange, thickness=.003, coils=40, radius=0.015)
spring.axis = ball.pos - ceiling.pos

## initial values
ball.p = mball*vector(0,0,0)

## improve the display
scene.autoscale = 0             ## don't let camera zoom in and out as ball moves
scene.center = vector(0,-L0,0)   ## move camera down to improve display visibility

## calculation loop

while t < 60:           ## make this short to read period off graph
    
## calculate force on ball by spring (note: requires calculation of L_vector)
    
## calculate net force on ball (note: has two contributions)

## apply momentum principle

## update position

## update axis of spring


## update time   
    t = t + deltat