`rad` |
SHGrid class instance of the radial component of the gravitational acceleration evaluated on an ellipsoid. |

`theta` |
SHGrid class instance of the theta component of the gravitational acceleration evaluated on an ellipsoid. |

`phi` |
SHGrid class instance of the phi component of the gravitational acceleration evaluated on an ellipsoid. |

`total` |
SHGrid class instance of the total gravitational acceleration with the normal gravity removed on an ellipsoid. |

`pot` |
SHGrid class instance of the gravitational potential evaluated on an ellipsoid. |

`gm` |
Gravitational constant time the mass of the body. |

`a` |
Semimajor axis of the reference ellipsoid. |

`f` |
Flattening of the reference ellipsoid, f = (a - b) / a. |

`omega` |
Angular rotation rate of the body. |

`normal_gravity` |
True if the normal gravity is removed from the total gravitational acceleration. |

`lmax` |
The maximum spherical harmonic degree resolvable by the grids. |

`lmax_calc` |
The maximum spherical harmonic degree of the gravitational potential used in creating the grids. |

`nlat` , `nlon` |
The number of latitude and longitude bands in the grids. |

`sampling` |
The longitudinal sampling scheme of the grids: either 1 for `nlon` = `nlat` or 2 for `nlon` = 2 * `nlat` . |