code: def galcencyl_to_vxvyvz(vR,vT,vZ,phi,vsun=[0.,1.,0.],Xsun=1.,Zsun=0.,
                          _extra_rot=True):
      
      vXg, vYg, vZg= cyl_to_rect_vec(vR,vT,vZ,phi)
      return galcenrect_to_vxvyvz(vXg,vYg,vZg,vsun=vsun,Xsun=Xsun,Zsun=Zsun,
                                  _extra_rot=_extra_rot)
docs: NAME:
  
         galcencyl_to_vxvyvz
  
      PURPOSE:
  
         transform cylindrical Galactocentric coordinates to XYZ (wrt Sun) coordinates for velocities
  
      INPUT:
  
         vR - Galactocentric radial velocity
  
         vT - Galactocentric tangential velocity
  
         vZ - Galactocentric vertical velocity
  
         phi - Galactocentric azimuth
  
         vsun - velocity of the sun in the GC frame ndarray[3] (can be array of same length as vRg; shape [3,N])
  
         Xsun - cylindrical distance to the GC (can be array of same length as vRg)
         
         Zsun - Sun's height above the midplane (can be array of same length as vRg)
  
         _extra_rot= (True) if True, perform an extra tiny rotation to align the Galactocentric coordinate frame with astropy's definition
  
      OUTPUT:
  
         vx,vy,vz
  
      HISTORY:
  
         2011-02-24 - Written - Bovy (NYU)
  
         2017-10-24 - Allowed vsun/Xsun/Zsun to be arrays - Bovy (NYU)