fitAstromErrModel

lsst.validate.drp.astromerrmodel.fitAstromErrModel(snr, dist)

Fit model of astrometric error from the LSST Overview paper:

http://arxiv.org/abs/0805.2366v4

Parameters:

snr : np.ndarray or astropy.unit.Quantity

Signal-to-noise ratio of photometric observations (dimensionless).

dist : np.ndarray or astropy.unit.Quantity

Scatter in measured positions (default: millarcsec)

Returns:

params : dict

Fitted model parameters. Fields are:

• C: Model scale factor (dimensionless).
• theta: Seeing (default: milliarcsec).
• sigmaSys: Systematic astrometric uncertainty (default: milliarcsec).