Coverage for python/lsst/sims/utils/CompoundCoordinateTransformations.py : 21%
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""" This file contains coordinate transformations that rely on both palpy and the contents of AstrometryUtils.py (basically, coordinate transformations that need to transform between observed geocentric RA, DEC and ICRS RA, Dec) """
"_raDecFromAltAz", "raDecFromAltAz", "getRotTelPos", "_getRotTelPos", "getRotSkyPos", "_getRotSkyPos"]
""" Convert RA, Dec, longitude, latitude and MJD into altitude, azimuth and parallactic angle using PALPY
@param [in] ra is RA in degrees. Can be a numpy array or a single value. Assumed to be in the International Celestial Reference System.
@param [in] dec is Dec in degrees. Can be a numpy array or a single value. Assumed to be in the International Celestial Reference System.
@param [in] obs is an ObservationMetaData characterizing the site of the telescope and the MJD of the observation
@param [in] includeRefraction is a boolean that turns refraction on and off (default True)
@param [out] altitude in degrees
@param [out] azimuth in degrees
@param [out] parallactic angle in degrees
WARNING: This method does not account for apparent motion due to parallax. This method is only useful for mapping positions on a theoretical celestial sphere. """
alt, az, pa = _altAzPaFromRaDec(np.radians(ra), np.radians(dec), obs, includeRefraction=includeRefraction)
return np.degrees(alt), np.degrees(az), np.degrees(pa)
""" Convert RA, Dec, longitude, latitude and MJD into altitude, azimuth and parallactic angle using PALPY
@param [in] raRad is RA in radians. Can be a numpy array or a single value. Assumed to be in the International Celestial Reference System.
@param [in] decRad is Dec in radians. Can be a numpy array or a single value. Assumed to be in the International Celestial Reference System.
@param [in] obs is an ObservationMetaData characterizing the site of the telescope and the MJD of the observation
@param [in] includeRefraction is a boolean that turns refraction on and off (default True)
@param [out] altitude in radians
@param [out] azimuth in radians
@param [out] parallactic angle in radians
WARNING: This method does not account for apparent motion due to parallax. This method is only useful for mapping positions on a theoretical focal plan to positions on the celestial sphere. """
are_arrays = _validate_inputs([raRad, decRad], ['ra', 'dec'], "altAzPaFromRaDec")
raObs, decObs = \ _observedFromICRS(raRad, decRad, obs_metadata=obs, epoch=2000.0, includeRefraction=includeRefraction)
lst = calcLmstLast(obs.mjd.UT1, obs.site.longitude_rad) last = lst[1] haRad = np.radians(last * 15.0) - raObs
if are_arrays: az, azd, azdd, \ alt, altd, altdd, \ pa, pad, padd = palpy.altazVector( haRad, decObs, obs.site.latitude_rad) else: az, azd, azdd, \ alt, altd, altdd, \ pa, pad, padd = palpy.altaz(haRad, decObs, obs.site.latitude_rad)
return alt, az, pa
""" Convert altitude and azimuth to RA and Dec
@param [in] alt is the altitude in degrees. Can be a numpy array or a single value.
@param [in] az is the azimuth in degrees. Cant be a numpy array or a single value.
@param [in] obs is an ObservationMetaData characterizing the site of the telescope and the MJD of the observation
@param [in] includeRefraction is a boolean that turns refraction on and off (default True)
@param [out] RA in degrees (in the International Celestial Reference System)
@param [out] Dec in degrees (in the International Celestial Reference System)
Note: This method is only accurate to within 0.01 arcsec near azimuth = 0 or pi """
ra, dec = _raDecFromAltAz(np.radians(alt), np.radians(az), obs, includeRefraction=includeRefraction)
return np.degrees(ra), np.degrees(dec)
""" Convert altitude and azimuth to RA and Dec
@param [in] altRad is the altitude in radians. Can be a numpy array or a single value.
@param [in] azRad is the azimuth in radians. Cant be a numpy array or a single value.
@param [in] obs is an ObservationMetaData characterizing the site of the telescope and the MJD of the observation
@param [in] includeRefraction is a boolean that turns refraction on and off (default True)
@param [out] RA in radians (in the International Celestial Reference System)
@param [out] Dec in radians (in the International Celestial Reference System)
Note: This method is only accurate to within 0.01 arcsec near azimuth = 0 or pi """
with np.errstate(invalid='ignore', divide='ignore'): are_arrays = _validate_inputs( [altRad, azRad], ['altRad', 'azRad'], "raDecFromAltAz")
lst = calcLmstLast(obs.mjd.UT1, obs.site.longitude_rad) last = lst[1] sinAlt = np.sin(altRad) cosLat = np.cos(obs.site.latitude_rad) sinLat = np.sin(obs.site.latitude_rad) decObs = np.arcsin(sinLat * sinAlt + cosLat * np.cos(altRad) * np.cos(azRad)) costheta = (sinAlt - np.sin(decObs) * sinLat) / (np.cos(decObs) * cosLat) if are_arrays: haRad0 = np.arccos(costheta) # Make sure there were no NaNs nanSpots = np.where(np.isnan(haRad0))[0] if np.size(nanSpots) > 0: haRad0[nanSpots] = 0.5 * np.pi * \ (1.0 - np.sign(costheta[nanSpots])) else: haRad0 = np.arccos(costheta) if np.isnan(haRad0): if np.sign(costheta) > 0.0: haRad0 = 0.0 else: haRad0 = np.pi
haRad = np.where(np.sin(azRad) >= 0.0, -1.0 * haRad0, haRad0) raObs = np.radians(last * 15.) - haRad
raRad, decRad = _icrsFromObserved(raObs, decObs, obs_metadata=obs, epoch=2000.0, includeRefraction=includeRefraction)
return raRad, decRad
""" @param [in] ra is the RA in degrees. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] dec is Dec in degrees. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] obs is an ObservationMetaData characterizing the telescope pointing and site.
@param [in] rotTel is rotTelPos in degrees (the angle of the camera rotator). Can be a numpy array or a single value. If a numpy array, should have the same length as ra and dec. In this case, each rotTel will be associated with the corresponding ra, dec pair.
@param [out] rotSkyPos in degrees
WARNING: As of 13 April 2015, this method does not agree with OpSim on the relationship between rotSkyPos and rotTelPos. This is due to a discrepancy between the time that OpSim uses as the MJD when calculating rotTelPos and the time that OpSim reports as being the actual expmjd of the exposure (rotTelPos is calculated at the beginning of the exposure; expmjd is reckoned at the middle of the exposure). """
rotSky = _getRotSkyPos(np.radians(ra), np.radians(dec), obs, np.radians(rotTel))
return np.degrees(rotSky)
""" @param [in] raRad is the RA in radians. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] decRad is Dec in radians. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] obs is an ObservationMetaData characterizing the telescope pointing and site.
@param [in] rotTelRad is rotTelPos in radians (the angle of the camera rotator). Can be a numpy array or a single value. If a numpy array, should have the same length as raRad and decRad. In this case, each rotTelRad will be associated with the corresponding raRad, decRad pair.
@param [out] rotSkyPos in radians
WARNING: As of 13 April 2015, this method does not agree with OpSim on the relationship between rotSkyPos and rotTelPos. This is due to a discrepancy between the time that OpSim uses as the MJD when calculating rotTelPos and the time that OpSim reports as being the actual expmjd of the exposure (rotTelPos is calculated at the beginning of the exposure; expmjd is reckoned at the middle of the exposure). """ altRad, azRad, paRad = _altAzPaFromRaDec(raRad, decRad, obs)
return (rotTelRad - paRad) % (2. * np.pi)
""" @param [in] ra is RA in degrees. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] dec is Dec in degrees. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] obs is an ObservationMetaData characterizing the telescope pointing and site.
@param [in] rotSky is rotSkyPos in degrees (the angle of the field of view relative to the South pole given a rotator angle). Can be a numpy array or a single value. If a numpy array, should have the same length as ra and dec. In this case, each rotSkyPos will be associated with the corresponding ra, dec pair.
@param [out] rotTelPos in degrees.
WARNING: As of 13 April 2015, this method does not agree with OpSim on the relationship between rotSkyPos and rotTelPos. This is due to a discrepancy between the time that OpSim uses as the MJD when calculating rotTelPos and the time that OpSim reports as being the actual expmjd of the exposure (rotTelPos is calculated at the beginning of the exposure; expmjd is reckoned at the middle of the exposure). """ rotTel = _getRotTelPos(np.radians(ra), np.radians(dec), obs, np.radians(rotSky))
return np.degrees(rotTel)
""" @param [in] raRad is RA in radians. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] decRad is Dec in radians. Can be a numpy array or a single value. (In the International Celestial Reference System)
@param [in] obs is an ObservationMetaData characterizing the telescope pointing and site.
@param [in] rotSkyRad is rotSkyPos in radians (the angle of the field of view relative to the South pole given a rotator angle). Can be a numpy array or a single value. If a numpy array, should have the same length as raRad and decRad. In this case, each rotSkyPos will be associated with the corresponding raRad, decRad pair.
@param [out] rotTelPos in radians.
WARNING: As of 13 April 2015, this method does not agree with OpSim on the relationship between rotSkyPos and rotTelPos. This is due to a discrepancy between the time that OpSim uses as the MJD when calculating rotTelPos and the time that OpSim reports as being the actual expmjd of the exposure (rotTelPos is calculated at the beginning of the exposure; expmjd is reckoned at the middle of the exposure). """ altRad, azRad, paRad = _altAzPaFromRaDec(raRad, decRad, obs)
return (rotSkyRad + paRad) % (2. * np.pi) |