def fit_eclipse_bottom(time, data, params, zero_eclipse_method="mean"):
"""Calculates the eclipse bottom to set the zero-point in the data
Args:
time: observational time (same units at orbital period)
data: observational data
params: dict of floats/numpy arrays, including
params.per - orbital period, same units as time
params.T0 - mid-transit time
params.p - ratio of the planet to the star's radius
params.b - impact parameter in units of stellar radius
params.a - semi-major axis in units of stellar radius
zero_eclipse_method (str):
Which method used to set zero-point -
"mean" - Use in-eclipse average value
"median" - Use in-eclipse median value
Returns:
eclipse bottom value
"""
if(zero_eclipse_method == "mean"):
calc_method = np.nanmean
elif(zero_eclipse_method == "median"):
calc_method = np.nanmedian
else:
raise ValueError("which_method should be mean or median!")
eclipse_bottom = 0.
period = params.per
TE = calc_eclipse_time(params)
# In some cases, the planet is never totally occulted.
# For those cases, fit eclipse with quadratic and return min value.
if((1. - params.p)**2 - params.b**2. < 0.):
# Find in-eclipse points
dur = transit_duration(params, which_duration='full')
ind = isInTransit(time, TE, period, 0.5*dur, boolOutput=True)
# Fit quadratic to eclipse to estimate minimum
coeffs = np.polyfit(time[ind], data[ind], 2)
eclipse_bottom = np.polyval(coeffs, -coeffs[1]/2./coeffs[0])
else:
# Find in-eclipse points
dur = transit_duration(params, which_duration='short')
ind = isInTransit(time, TE, period, 0.5*dur, boolOutput=True)
eclipse_bottom = calc_method(data[ind])
return eclipse_bottom
def sanity_inTransitExample_2(self):
"""
inTransit---Series of points in time
"""
from PyAstronomy import pyasl
import numpy as np
# Times of interest
times = 2476357.756234 + np.linspace(0.0, 5.0, 300)
# Define some (arbitrary) transit parameters
T0 = 2475123.01245
period = 3.4789112
duration = 2.2/24.0
# Check whether the time is in-transit
print "Indices if time points within transit: ",
print pyasl.isInTransit(times, T0, period, duration/2.0)
print
print "For each time point, a flag indicating whether it"
print "is in- or off-transit:"
print pyasl.isInTransit(times, T0, period, duration/2.0, boolOutput=True)
def sanity_inTransitExample_1(self):
"""
inTransit---individual point in time
"""
from PyAstronomy import pyasl
# Time of interest
time = 2476357.756234
# Define some (arbitrary) transit parameters
T0 = 2475123.01245
period = 3.4789112
duration = 2.2/24.0
# Check whether the time is in-transit
print "Time is within transit? ",
if not pyasl.isInTransit(time, T0, period, duration/2.0):
print "No"
else:
print "Yes"
