positionRms

lsst.validate.drp.util.positionRms(ra_mean, dec_mean, ra, dec)

Calculate the RMS between an array of coordinates and a reference (mean) position.

Parameters:

ra_mean : float

Mean RA in radians.

dec_mean : float

Mean Dec in radians.

ra : numpy.array [float]

Array of RA in radians.

dec : numpy.array [float]

Array of Dec in radians.

Returns:

pos_rms : float

RMS scatter of positions in milliarcseconds.

Notes

The RMS of a single-element array will be returned as 0. The RMS of an empty array will be returned as NaN.