code: def getcosIm(alat):
      
  
      alat = np.float64(alat)
  
      return np.cos(np.radians(alat))/np.sqrt(4 - 3*np.cos(np.radians(alat))**2)
docs: Computes cosIm from modified apex latitude.
  
      Parameters
      ==========
      alat : array_like
          Modified apex latitude
  
      Returns
      =======
      cosIm : ndarray or float