def _hcc_hg(self, x, y, z):
"""Converts hcc coordinates to Stonyhurst heliographic.
x - x coordinate in meters
y - y coordinate in meters
z - z coordinate in meters
Calculations taken and shortened
from sunpy.wcs.
"""
cosb = M.cos(M.deg2rad(self.B0))
sinb = M.sin(M.deg2rad(self.B0))
hecr = M.sqrt(x**2 + y**2 + z**2)
hgln = M.arctan2(x, z*cosb - y*sinb) \
+ M.deg2rad(self.L0)
hglt = M.arcsin((y * cosb + z * sinb)/hecr)
return hgln*180/np.pi, hglt*180/np.pi
