# chaosmagpy.coordinate_utils.basevectors_sm¶

chaosmagpy.coordinate_utils.basevectors_sm(time, dipole=None)[source]

Computes the unit base vectors of the SM coordinate system with respect to the standard geographic coordinate system (GEO).

Parameters:
timefloat or ndarray, shape (…)

Time given as modified Julian date, i.e. with respect to the date 0h00 January 1, 2000 (mjd2000).

dipolendarray, shape (3,), optional

Dipole spherical harmonics $$g_1^0$$, $$g_1^1$$ and $$h_1^1$$. Defaults to basicConfig['params.dipole'].

Returns:
sm_1, sm_2, sm_3ndarray, shape (…, 3)

SM unit base vectors. The leading dimension agrees with the shape of time, while the last dimension contains the unit vector components in terms of GEO.