pygaia/errors/astrometric.py
def totalProperMotionErrorSkyAvg(G, vmini, extension=0.0):
  """
  Calculate the sky averaged total proper motion error from G and (V-I). This refers to the error on the
  length of the proper motion vector.

  NOTE! THE ERRORS ARE FOR PROPER MOTIONS IN THE ICRS (I.E., RIGHT ASCENSION, DECLINATION). MAKE SURE
  YOUR SIMULATED ASTROMETRY IS ALSO ON THE ICRS.

  Parameters
  ----------

  G     - Value(s) of G-band magnitude.
  vmini - Value(s) of (V-I) colour.

  Keywords
  --------

  extension - Add this amount of years to the mission lifetime and scale the errors accordingly.

  Returns
  -------

  The error on the total proper motion in micro-arcsecond/year.
  """
  factor = errorScalingMissionLength(extension, -1.5)
  parallaxError = parallaxErrorSkyAvg(G, vmini)*factor
  return _scalingForProperMotions['Total']*parallaxError
def totalProperMotionErrorSkyAvg(G, vmini, extension=0.0):
  """
  Calculate the sky averaged total proper motion error from G and (V-I). This refers to the error on the
  length of the proper motion vector.

  NOTE! THE ERRORS ARE FOR PROPER MOTIONS IN THE ICRS (I.E., RIGHT ASCENSION, DECLINATION). MAKE SURE
  YOUR SIMULATED ASTROMETRY IS ALSO ON THE ICRS.

  Parameters
  ----------

  G     - Value(s) of G-band magnitude.
  vmini - Value(s) of (V-I) colour.

  Keywords
  --------

  extension - Add this amount of years to the mission lifetime and scale the errors accordingly.

  Returns
  -------

  The error on the total proper motion in micro-arcsecond/year.
  """
  factor = errorScalingMissionLength(extension, -1.5)
  parallaxError = parallaxErrorSkyAvg(G, vmini)*factor
  return _scalingForProperMotions['Total']*parallaxError
Calculate the sky averaged total proper motion error from G and (V-I). This refers to the error on the
  length of the proper motion vector.

  NOTE! THE ERRORS ARE FOR PROPER MOTIONS IN THE ICRS (I.E., RIGHT ASCENSION, DECLINATION). MAKE SURE
  YOUR SIMULATED ASTROMETRY IS ALSO ON THE ICRS.

  Parameters
  ----------

  G     - Value(s) of G-band magnitude.
  vmini - Value(s) of (V-I) colour.

  Keywords
  --------

  extension - Add this amount of years to the mission lifetime and scale the errors accordingly.

  Returns
  -------

  The error on the total proper motion in micro-arcsecond/year.