Why encapsulation is useful

import math

def degreesToRadians(degrees):
  radians=(degrees/360)*2*math.pi
  return radians

def degreesToFraction(degrees):
  radians=degreesToRadians(degrees)
  fraction=math.tan(radians)
  return fraction

def printDegreesToFractionTable():
  print 'degrees\tfraction (m/m)'
  slopeDegrees = 0.0
  while slopeDegrees < 30.0:
    slopeFraction=degreesToFraction(slopeDegrees)
    print slopeDegrees, '\t', slopeFraction
    slopeDegrees=slopeDegrees+5.0

aFraction=degreesToFraction(45)