text: from __future__ import division
  from math import pi, sqrt, sin, cos
  
  # a python binding of https://on4wp7.codeplex.com/SourceControl/changeset/view/21483#353936
  
  # Krasovsky 1940
  #
  # a = 6378245.0, 1/f = 298.3
  # b = a * (1 - f)
  # ee = (a^2 - b^2) / a^2
  a = 6378245.0
  ee = 0.00669342162296594323
  
  
  # World Geodetic System ==> Mars Geodetic System
  def transform(wgLat, wgLon):
      """
      transform(latitude,longitude) , WGS84
      return (latitude,longitude) , GCJ02
      """
      if (outOfChina(wgLat, wgLon)):
          mgLat = wgLat
          mgLon = wgLon
          return
      dLat = transformLat(wgLon - 105.0, wgLat - 35.0)
      dLon = transformLon(wgLon - 105.0, wgLat - 35.0)
      radLat = wgLat / 180.0 * pi
      magic = sin(radLat)
      magic = 1 - ee * magic * magic
      sqrtMagic = sqrt(magic)
      dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi)
      dLon = (dLon * 180.0) / (a / sqrtMagic * cos(radLat) * pi)
      mgLat = wgLat + dLat
      mgLon = wgLon + dLon
      return mgLat, mgLon
  
  
  def outOfChina(lat, lon):
      if (lon < 72.004 or lon > 137.8347):
          return True
      if (lat < 0.8293 or lat > 55.8271):
          return True
      return False
  
  
  def transformLat(x, y):
      ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * sqrt(abs(x))
      ret += (20.0 * sin(6.0 * x * pi) + 20.0 * sin(2.0 * x * pi)) * 2.0 / 3.0
      ret += (20.0 * sin(y * pi) + 40.0 * sin(y / 3.0 * pi)) * 2.0 / 3.0
      ret += (160.0 * sin(y / 12.0 * pi) + 320 * sin(y * pi / 30.0)) * 2.0 / 3.0
      return ret
  
  
  def transformLon(x, y):
      ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * sqrt(abs(x))
      ret += (20.0 * sin(6.0 * x * pi) + 20.0 * sin(2.0 * x * pi)) * 2.0 / 3.0
      ret += (20.0 * sin(x * pi) + 40.0 * sin(x / 3.0 * pi)) * 2.0 / 3.0
      ret += (150.0 * sin(x / 12.0 * pi) + 300.0 * sin(x / 30.0 * pi)) * 2.0 / 3.0
      return ret
  
  
  if __name__ == "__main__":
      WGS84_Lat = 23.123161666666668
      WGS84_Long = 113.29841666666667
      print(transform(WGS84_Lat, WGS84_Long))
  