Source code for lsst.sims.maf.stackers.nFollowStacker

from builtins import zip
import numpy as np
from .baseStacker import BaseStacker
from .coordStackers import raDec2AltAz

__all__ = ['findTelescopes', 'NFollowStacker']


[docs]def findTelescopes(minSize=3.): """Finds telescopes larger than minSize, from list of large telescopes based on http://astro.nineplanets.org/bigeyes.html. Returns ------- np.recarray Array of large telescopes with columns [aperture, name, lat, lon]. """ # Aperture Name Location http://astro.nineplanets.org/bigeyes.html telescopes = [ [10.4, 'Gran Canarias', 'La Palma'], [10.0, 'Keck', 'Mauna Kea'], [10.0, 'Keck II', 'Mauna Kea'], [9.2, 'SALT', 'South African Astronomical Observatory'], [9.2, 'Hobby-Eberly', 'Mt. Fowlkes'], [8.4, 'Large Binocular Telescope', 'Mt. Graham'], [8.3, 'Subaru', 'Mauna Kea'], [8.2, 'Antu', 'Cerro Paranal'], [8.2, 'Kueyen', 'Cerro Paranal'], [8.2, 'Melipal', 'Cerro Paranal'], [8.2, 'Yepun', 'Cerro Paranal'], [8.1, 'Gemini North', 'Mauna Kea'], [8.1, 'Gemini South', 'Cerro Pachon'], [6.5, 'MMT', 'Mt. Hopkins'], [6.5, 'Walter Baade', 'La Serena'], [6.5, 'Landon Clay', 'La Serena'], [6.0, 'Bolshoi Teleskop Azimutalnyi', 'Nizhny Arkhyz'], [6.0, 'LZT', 'British Columbia'], [5.0, 'Hale', 'Palomar Mountain'], [4.3, 'Dicovery Channel', 'Lowell Observatory'], [4.2, 'William Herschel', 'La Palma'], [4.2, 'SOAR', 'Cerro Pachon'], [4.2, 'LAMOST', 'Xinglong Station'], [4.0, 'Victor Blanco', 'Cerro Tololo'], [4.0, 'Vista', 'Cerro Paranal'], [3.9, 'Anglo-Australian', 'Coonabarabran'], [3.8, 'Mayall', 'Kitt Peak'], [3.8, 'UKIRT', 'Mauna Kea'], [3.6, '360', 'Cerro La Silla'], [3.6, 'Canada-France-Hawaii', 'Mauna Kea'], [3.6, 'Telescopio Nazionale Galileo', 'La Palma'], [3.5, 'MPI-CAHA', 'Calar Alto'], [3.5, 'New Technology', 'Cerro La Silla'], [3.5, 'ARC', 'Apache Point'], [3.5, 'WIYN', 'Kitt Peak'], [3.0, 'Shane', 'Mount Hamilton'], [3.0, 'NASA IRTF', 'Mauna Kea'], ] scopes = np.zeros(len(telescopes), dtype = list(zip( ['aperture', 'name', 'lat', 'lon'], [float, (np.str, 38), float, float]))) # name, lat (S negative), lon (W negative) observatories = [ ['Cerro Paranal', -24, 38, -70, 24], ['Nizhny Arkhyz', 43, 39, 41, 26], ['Cerro La Silla', -29, 15, -70, 44], ['Lowell Observatory', 35, 12, -111, 40], ['Apache Point', 32, 47, -105, 49], ['Mount Hamilton', 37, 21, -121, 38], ['South African Astronomical Observatory', -32, 23, 20, 49], ['Cerro Pachon', -30, 20, -70, 59], ['Coonabarabran', -31, 17, 149, 0o4], ['Mt. Fowlkes', 30, 40, -104, 1], ['La Palma', 28, 46, -17, 53], ['Mt. Graham', 32, 42, -109, 53], ['Calar Alto', 37, 13, -2, 33], ['British Columbia', 49, 17, -122, 34], ['Kitt Peak', 31, 57, -111, 37], ['La Serena', -30, 10, -70, 48], ['Palomar Mountain', 33, 21, -116, 52], ['Xinglong Station', 40, 23, 105, 50], ['Mt. Hopkins', 31, 41, -110, 53], ['Cerro Tololo', -30, 10, -70, 49], ['Mauna Kea', 19, 50, -155, 28] ] # Make a nice little dict to look up the observatory positions obs = {} for i, ob in enumerate(observatories): obs[ob[0]] = [(np.abs(ob[1])+ob[2]/60.)*(ob[1]/np.abs(ob[1])), (np.abs(ob[3])+ob[4]/60.)*(ob[3]/np.abs(ob[3]))] for i, telescope in enumerate(telescopes): scopes['aperture'][i] = telescope[0] scopes['name'][i] = telescope[1] scopes['lat'][i], scopes['lon'][i] = obs[telescope[2]] scopes = scopes[np.where(scopes['aperture'] >= minSize)] return scopes
[docs]class NFollowStacker(BaseStacker): """Add the number of telescopes ('nObservatories') that could follow up any visit at (any of the) times in timeStep, specifying the minimum telescope size (in meters) and airmass limit. Parameters ---------- minSize: float, opt The minimum telescope aperture to use, in meters. Default 3.0. airmassLimit: float, opt The maximum airmass allowable at the follow-up observatory. Default 2.5. timeSteps: np.array or list of floats, opt The timesteps to check for followup opportunities, in hours. Default is np.arange(0.5, 12., 3.0). mjdCol: str, opt The exposure MJD column name. Default 'observationStartMJD'. raCol: str, opt The RA column name. Default 'fieldRA'. decCol: str, opt The Dec column name. Default 'fieldDec'. raDecDeg: bool, opt Flag whether RA/Dec are in degrees (True) or radians (False). """ colsAdded = ['nObservatories'] def __init__(self, minSize=3.0, airmassLimit=2.5, timeSteps=np.arange(0.5, 12., 3.0), mjdCol='observationStartMJD', raCol='fieldRA', decCol='fieldDec', degrees=True): self.mjdCol = mjdCol self.raCol = raCol self.decCol = decCol self.degrees = degrees self.colsAddedDtypes = [int] self.colsReq = [self.mjdCol, self.raCol, self.decCol] self.units = ['#'] self.airmassLimit = airmassLimit self.timeSteps = timeSteps self.telescopes = findTelescopes(minSize = minSize) def _run(self, simData, cols_present=False): if cols_present: return simData if self.degrees: ra = np.radians(simData[self.raCol]) dec = np.radians(simData[self.decCol]) else: ra = simData[self.raCol] dec = simData[self.decCol] for obs in self.telescopes: obsGotIt = np.zeros(len(simData[self.raCol]), int) obsLon = np.radians(obs['lon']) obsLat = np.radians(obs['lat']) for step in self.timeSteps: alt, az = raDec2AltAz(ra, dec, obsLon, obsLat, simData[self.mjdCol] + step / 24.0, altonly=True) airmass = 1. / (np.cos(np.pi / 2. - alt)) followed = np.where((airmass <= self.airmassLimit) & (airmass >= 1.)) # If the observatory got an observation, save this into obsGotIt. # obsGotIt will be 1 if ANY of the times got an observation. obsGotIt[followed] = 1 # If an observatory got an observation, count it in nObservatories. simData['nObservatories'] += obsGotIt return simData