def __init__(self, name, single=False, sig_RpRs=0.001, **kwargs):
"""Instantiate the pysyzygy model."""
# The planet/transit model ID
assert type(name) is str, "Arg `name` must be a string."
self.name = name
# Skip if pysyzygy not installed
if ps is None:
return
# The transit model
self._transit = ps.Transit(**kwargs)
# Compute the depth
times = kwargs.get('times', None)
if times is not None:
self.t0 = times[0]
else:
self.t0 = kwargs.get('t0', 0.)
self.per = kwargs.get('per', 10.)
self.single = single
self.depth = (1. - self._transit([self.t0]))[0]
# Approximate variance on the depth
self.var_depth = (2 * sig_RpRs) ** 2
# Save the kwargs
self.params = kwargs
def Transit(time, t0=0., dur=0.1, per=3.56789, depth=0.001, **kwargs):
'''
A `Mandel-Agol <http://adsabs.harvard.edu/abs/2002ApJ...580L.171M>`_
transit model, but with the depth and the duration as primary
input variables.
:param numpy.ndarray time: The time array
:param float t0: The time of first transit in units of \
:py:obj:`BJD` - 2454833.
:param float dur: The transit duration in days. Don't go too crazy on \
this one -- very small or very large values will break the \
inverter. Default 0.1
:param float per: The orbital period in days. Default 3.56789
:param float depth: The fractional transit depth. Default 0.001
:param dict kwargs: Any additional keyword arguments, passed directly \
to :py:func:`pysyzygy.Transit`
:returns tmod: The transit model evaluated at the same times as the \
:py:obj:`time` array
'''
if ps is None:
raise Exception("Unable to import `pysyzygy`.")
# Note that rhos can affect RpRs, so we should really do this iteratively,
# but the effect is pretty negligible!
RpRs = Get_RpRs(depth, t0=t0, per=per, **kwargs)
rhos = Get_rhos(dur, t0=t0, per=per, **kwargs)
return ps.Transit(t0=t0, per=per, RpRs=RpRs, rhos=rhos, **kwargs)(time)
def Dur(rhos, **kwargs):
t0 = kwargs.get('t0', 0.)
time = np.linspace(t0 - 0.5, t0 + 0.5, 1000)
try:
t = time[np.where(ps.Transit(rhos=rhos, **kwargs)(time) < 1)]
except:
return 0.
return t[-1] - t[0]
def flux(self, time, planets=None, cadence='lc'):
'''
'''
# Ensure it's a list
if planets is None:
planets = self.planets
elif type(planets) is str:
planets = [planets]
# Compute flux for each planet
flux = np.ones_like(time)
for planet in planets:
if cadence == 'lc':
model = ps.Transit(per=self.period[planet],
b=self.b[planet],
RpRs=self.RpRs[planet],
t0=self.t0[planet],
rhos=self.rhos,
ecc=self.ecc[planet],
w=self.w[planet] * np.pi / 180.,
u1=self.u1,
u2=self.u2,
times=self.times[planet])
else:
model = ps.Transit(per=self.period[planet],
b=self.b[planet],
RpRs=self.RpRs[planet],
t0=self.t0[planet],
rhos=self.rhos,
ecc=self.ecc[planet],
w=self.w[planet] * np.pi / 180.,
u1=self.u1,
u2=self.u2,
times=self.times[planet],
exptime=ps.KEPSHRTCAD)
flux *= model(time)
return flux
def __init__(self, depth=1, dur=0.1, **kwargs):
"""Initialize the pysyzygy model."""
if ps is None:
return
kwargs.pop('t0', None)
kwargs.pop('times', None)
# Update kwargs with correct duration
kwargs.update({'per': 3.56789})
kwargs.update({'rhos': Get_rhos(dur, **kwargs)})
# Transit window size w/ padding
window = dur * 3
t = np.linspace(-window / 2, window / 2, 5000)
# Construct a transit model
trn = ps.Transit(t0=0., **kwargs)
transit_model = trn(t)
transit_model -= 1
transit_model *= depth / (1 - trn([0.])[0])
self.x = t
self.y = transit_model
def negll(x):
'''
'''
RpRs, bcirc, q1, q2 = x
psm = ps.Transit(per=per,
q1=q1,
q2=q2,
RpRs=RpRs,
rhos=rhos,
tN=tN,
ecw=0.,
esw=0.,
bcirc=bcirc,
MpMs=0.)
ll = 0
# Loop over all quarters
for q in inp.quarters:
# Empty?
if len(pdata[q]['time']) == 0:
continue
# Info for this quarter
crwd = tdata[q]['crwd']
c = tdata[q]['dvec'][iPLD:]
x = tdata[q]['dvec'][:iPLD]
inp.kernel.pars = x
gp = george.GP(inp.kernel)
# Loop over all transits
for time, fpix, perr in zip(tdata[q]['time'], tdata[q]['fpix'],
tdata[q]['perr']):
# Compute the transit model
try:
tmod = psm(time, 'binned')
except Exception as e:
if inp.debug:
print("Transit optimization exception:", str(e))
return 1.e20
# Compute the PLD model
pmod, ypld, yerr = PLDFlux(c,
fpix,
perr,
tmod,
crowding=crwd)
# Compute the GP model
try:
gp.compute(time, yerr)
except Exception as e:
if inp.debug:
print("Transit optimization exception:", str(e))
return 1.e20
ll += gp.lnlikelihood(ypld)
if inp.debug:
print("Likelihood: ", ll)
return -ll
def ComputePLD(input_file=None, clobber=False):
'''
'''
# Load inputs
inp = Input(input_file)
detpath = os.path.join(inp.datadir, str(inp.id), '_detrend')
iPLD = len(inp.kernel.pars)
# Have we already detrended?
pdata = GetData(inp.id, data_type='prc', datadir=inp.datadir)
tdata = GetData(inp.id, data_type='trn', datadir=inp.datadir)
if not (inp.clobber or clobber):
try:
for q in pdata:
if len(pdata[q]['time']) == 0:
continue
if len(pdata[q]['pmod']) == 0:
raise ValueError("Pixel model list is empty.")
# Data is already detrended
if not inp.quiet:
print("Using existing PLD info.")
return True
except ValueError:
# We're going to have to compute
pass
# Get some info
info = DownloadInfo(inp.id,
inp.dataset,
trninfo=inp.trninfo,
inject=inp.inject,
datadir=inp.datadir,
clobber=False,
ttvs=inp.ttvs,
pad=inp.padbkg)
per = info['per']
rhos = info['rhos']
tN = info['tN']
# Optimize transit model
if len(tN):
if not inp.quiet:
print("Computing approximate transit model...")
# This lets us approximately solve for RpRs, bcirc, q1, q2
def negll(x):
'''
'''
RpRs, bcirc, q1, q2 = x
psm = ps.Transit(per=per,
q1=q1,
q2=q2,
RpRs=RpRs,
rhos=rhos,
tN=tN,
ecw=0.,
esw=0.,
bcirc=bcirc,
MpMs=0.)
ll = 0
# Loop over all quarters
for q in inp.quarters:
# Empty?
if len(pdata[q]['time']) == 0:
continue
# Info for this quarter
crwd = tdata[q]['crwd']
c = tdata[q]['dvec'][iPLD:]
x = tdata[q]['dvec'][:iPLD]
inp.kernel.pars = x
gp = george.GP(inp.kernel)
# Loop over all transits
for time, fpix, perr in zip(tdata[q]['time'], tdata[q]['fpix'],
tdata[q]['perr']):
# Compute the transit model
try:
tmod = psm(time, 'binned')
except Exception as e:
if inp.debug:
print("Transit optimization exception:", str(e))
return 1.e20
# Compute the PLD model
pmod, ypld, yerr = PLDFlux(c,
fpix,
perr,
tmod,
crowding=crwd)
# Compute the GP model
try:
gp.compute(time, yerr)
except Exception as e:
if inp.debug:
print("Transit optimization exception:", str(e))
return 1.e20
ll += gp.lnlikelihood(ypld)
if inp.debug:
print("Likelihood: ", ll)
return -ll
# Run the optimizer.
init = [info['RpRs'], info['b'], 0.25, 0.25]
bounds = [[1.e-4, 0.5], [0., 0.95], [0., 1.], [0., 1.]]
res = fmin_l_bfgs_b(negll, init, approx_grad=True, bounds=bounds)
RpRs, bcirc, q1, q2 = res[0]
# Save these!
np.savez(os.path.join(inp.datadir, str(inp.id), '_data', 'rbqq.npz'),
RpRs=RpRs,
bcirc=bcirc,
q1=q1,
q2=q2)
# Pre-compute the transit model
psm = ps.Transit(per=per,
q1=q1,
q2=q2,
RpRs=RpRs,
rhos=rhos,
tN=tN,
ecw=0.,
esw=0.,
bcirc=bcirc,
MpMs=0.)
# Now, finally, compute the PLD flux and errors
for q in inp.quarters:
if len(pdata[q]['time']) == 0:
continue
# PLD and GP coeffs for this quarter
c = pdata[q]['dvec'][iPLD:]
x = pdata[q]['dvec'][:iPLD]
# Crowding parameter
crwd = pdata[q]['crwd']
# Reset
tdata[q]['pmod'] = []
tdata[q]['yerr'] = []
tdata[q]['ypld'] = []
pdata[q]['pmod'] = []
pdata[q]['yerr'] = []
pdata[q]['ypld'] = []
# Loop over all transits
for time, fpix, perr in zip(tdata[q]['time'], tdata[q]['fpix'],
tdata[q]['perr']):
# Compute the transit model
if len(tN):
tmod = psm(time, 'binned')
else:
tmod = 1.
# Compute the PLD model
pmod, ypld, yerr = PLDFlux(c, fpix, perr, tmod, crowding=crwd)
# The pixel model
tdata[q]['pmod'].append(pmod)
# The errors on our PLD-detrended flux
tdata[q]['yerr'].append(yerr)
# The PLD-detrended, transitless flux
# NOTE: This is just for verification purposes, since we used
# a very quick transit optimization to compute this!
tdata[q]['ypld'].append(ypld)
# Now loop over all chunks in the full (processed) data
for time, fpix, perr in zip(pdata[q]['time'], pdata[q]['fpix'],
pdata[q]['perr']):
# Compute the transit model
if len(tN):
tmod = psm(time, 'binned')
else:
tmod = 1.
# Compute the PLD model
pmod, ypld, yerr = PLDFlux(c, fpix, perr, tmod, crowding=crwd)
# The pixel model
pdata[q]['pmod'].append(pmod)
# The errors on our PLD-detrended flux
pdata[q]['yerr'].append(yerr)
# The PLD-detrended, transitless flux
# NOTE: This is just for verification purposes, since we used
# a very quick transit optimization to compute this!
pdata[q]['ypld'].append(ypld)
np.savez_compressed(os.path.join(inp.datadir, str(inp.id), '_data',
'trn.npz'),
data=tdata,
hash=GitHash())
np.savez_compressed(os.path.join(inp.datadir, str(inp.id), '_data',
'prc.npz'),
data=pdata,
hash=GitHash())
return True
def PlotTransits(input_file = None, ax = None, clobber = False):
'''
'''
# Try to use Agg for plotting
pl.switch_backend('Agg')
# Input file
inp = Input(input_file)
detpath = os.path.join(inp.datadir, str(inp.id), '_detrend')
iPLD = len(inp.kernel.pars)
# Have we done this already?
if ax is None and not (inp.clobber or clobber):
if os.path.exists(os.path.join(inp.datadir, str(inp.id), '_plots', 'folded.png')):
return None, None
if ax is None and not inp.quiet:
print("Plotting transits...")
# Load the info
info = DownloadInfo(inp.id, inp.dataset, trninfo = inp.trninfo,
inject = inp.inject, datadir = inp.datadir,
clobber = False, ttvs = inp.ttvs,
pad = inp.padbkg)
tdur = info['tdur']
tN = info['tN']
per = info['per']
rhos = info['rhos']
# Are there any transits?
if len(tN) == 0:
return None, None
if not (inp.clobber or clobber) and os.path.exists(os.path.join(inp.datadir, str(inp.id), '_data', 'fold.npz')):
foo = np.load(os.path.join(inp.datadir, str(inp.id), '_data', 'fold.npz'))
t = foo['t']
f = foo['f']
else:
# Get our transit data
t = np.array([], dtype = float)
f = np.array([], dtype = float)
tdata = GetData(inp.id, data_type = 'trn', datadir = inp.datadir)
# Transit model
try:
foo = np.load(os.path.join(inp.datadir, str(inp.id), '_data', 'rbqq.npz'))
RpRs = foo['RpRs']
bcirc = foo['bcirc']
q1 = foo['q1']
q2 = foo['q2']
except FileNotFoundError:
raise FileNotFoundError("Unable to load transit parameters.")
psm = ps.Transit(per = per, q1 = q1, q2 = q2, RpRs = RpRs, rhos = rhos,
tN = tN, ecw = 0., esw = 0., bcirc = bcirc, MpMs = 0.)
# Loop over all quarters
for q in inp.quarters:
# Empty?
if len(tdata[q]['time']) == 0:
continue
# Info for this quarter
crwd = tdata[q]['crwd']
c = tdata[q]['dvec'][iPLD:]
x = tdata[q]['dvec'][:iPLD]
inp.kernel.pars = x
gp = george.GP(inp.kernel)
# Loop over all transits
for time, fpix, perr in zip(tdata[q]['time'], tdata[q]['fpix'], tdata[q]['perr']):
# Compute the transit model
tmod = psm(time, 'binned')
# Compute the PLD model
pmod, ypld, yerr = PLDFlux(c, fpix, perr, tmod, crowding = crwd)
# Compute the GP model
gp.compute(time, yerr)
mu, _ = gp.predict(ypld, time)
t = np.append(t, time)
# TODO: Verify that this is in fact the correct way
# to whiten the transit!
f = np.append(f, np.sum(fpix, axis = 1) / (mu + pmod))
# Fold the data
t -= np.array([tN[np.argmin(np.abs(tN - ti))] for ti in t])
# Save it!
np.savez(os.path.join(inp.datadir, str(inp.id), '_data', 'fold.npz'), t = t, f = f)
# Plot
if ax is None:
userax = False
fig, ax = pl.subplots(1, 1, figsize = (14, 6))
else:
userax = True
xlim = (-inp.padtrn * tdur / 2., inp.padtrn * tdur / 2.)
fvis = f[np.where((t > xlim[0]) & (t < xlim[1]))]
minf = np.min(fvis)
maxf = np.max(fvis)
padf = 0.1 * (maxf - minf)
ylim = (minf - padf, maxf + padf)
ax.plot(t, f, 'k.', alpha = min(1.0, max(0.05, 375. / len(fvis))))
# Bin to median
bins = np.linspace(xlim[0], xlim[1], inp.tbins)
delta = bins[1] - bins[0]
idx = np.digitize(t, bins)
med = [np.median(f[idx == k]) for k in range(inp.tbins)]
ax.plot(bins - delta / 2., med, 'ro', alpha = 0.75)
# Is this a fake transit injection? If so, plot the true model
if inp.inject is not None and inp.inject != {}:
pskwargs = dict(inp.inject)
pskwargs.pop('tN', None)
pskwargs.update({'t0': 0.})
psm = ps.Transit(**pskwargs)
t0 = np.linspace(-inp.padtrn * tdur / 2., inp.padtrn * tdur / 2., 1000)
f0 = psm(t0, 'binned')
ax.plot(t0, f0, 'r--')
ax.set_xlim(xlim)
ax.set_ylim(ylim)
if not userax:
ax.set_title('Folded Whitened Transits', fontsize = 24)
ax.set_xlabel('Time (days)', fontsize = 22)
ax.set_ylabel('Flux', fontsize = 22)
if not userax:
fig.savefig(os.path.join(inp.datadir, str(inp.id), '_plots', 'folded.png'), bbox_inches = 'tight')
return fig, ax
else:
return ax
# Get the raw pixel flux
calc = False
ncad = 3000
time = np.linspace(0, 13.7 * 2, ncad)
if calc:
fpix = GenerateData(ncad=ncad)
np.savez('fpix.npz', fpix=fpix)
else:
fpix = np.load('fpix.npz')['fpix']
fpix[np.where(np.isnan(fpix))] = 0.
flux_notrn = np.sum(fpix, axis=(1, 2))
# Add a transit model
trn = ps.Transit(t0=7., RpRs=0.03, per=12, rhos=0.01)
transit = trn(time)
fpix *= transit.reshape(-1, 1, 1)
# Get the SAP flux
flux = np.sum(fpix, axis=(1, 2))
med = np.nanmedian(flux)
# Regress with 2nd order PLD. Note that
# we are cheating a bit since I'm regressing
# on the flux with *no transit* model.
# In reality, we would *jointly fit*
# the systematics and the transit, but
# this is a shortcut.
D = fpix.reshape(ncad, -1) / flux.reshape(-1, 1)
D = np.hstack((D, D * D))
def plot_random_planets(self, ncurves=50, over=0.1, pmin=None, pmax=None,
show_vsys=False, show_trend=False):
"""
Display the RV data together with curves from the posterior predictive.
A total of `ncurves` random samples are chosen,
and the Keplerian curves are calculated covering 100 + `over`%
of the timespan of the data.
"""
samples = self.get_sorted_planet_samples()
if self.max_components > 0:
samples, mask = \
self.apply_cuts_period(samples, pmin, pmax, return_mask=True)
else:
mask = np.ones(samples.shape[0], dtype=bool)
t = self.data[:,0].copy()
tt = np.linspace(t[0]-over*t.ptp(), t[-1]+over*t.ptp(),
10000+int(100*over))
y = self.data[:,1].copy()
yerr = self.data[:,2].copy()
# select random `ncurves` indices
# from the (sorted, period-cut) posterior samples
ii = np.random.randint(samples.shape[0], size=ncurves)
_, ax = plt.subplots(1,1)
## plot the Keplerian curves
for i in ii:
f = np.zeros_like(tt)
pars = samples[i, :].copy()
nplanets = pars.size / self.n_dimensions
for j in range(int(nplanets)):
P = pars[j + 0*self.max_components]
if P==0.0:
continue
RpRs = pars[j + 1*self.max_components]
aRs = pars[j + 2*self.max_components]
phi = pars[j + 3*self.max_components]
Tc = t[0] + (P*phi)
try:
f += ps.Transit(per=P, aRs=aRs, RpRs=RpRs, t0=Tc)(tt) - 1.0
except:
print('Failed for:', P, RpRs, aRs, Tc)
# v += keplerian(tt, P, K, ecc, w, t0, 0.)
f0 = self.posterior_sample[mask][i, -1]
f += f0
ax.plot(tt, f, alpha=0.2, color='k')
# if show_vsys:
# ax.plot(t, vsys*np.ones_like(t), alpha=0.2, color='r', ls='--')
## plot the data
ax.errorbar(t, y, yerr, fmt='.')
ax.set(xlabel='Time [days]', ylabel='Flux []')
plt.tight_layout()
def DownloadKeplerData(
id,
datadir='',
long_cadence=True,
clobber=False,
bad_bits=[1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17],
aperture='optimal',
quarters=range(18),
quiet=False,
inject={},
ttvs=False,
pad=2.0,
trninfo={},
**kwargs):
'''
'''
if not clobber:
try:
# For some reason, numpy saves it as a 0-d array.
# See http://stackoverflow.com/questions/8361561/recover-dict-from-0-d-numpy-array
data = np.load(os.path.join(datadir, str(id), '_data',
'raw.npz'))['data'][()]
if not quiet:
print("Loading saved TPF data...")
return data
except FileNotFoundError:
pass
# Create directories
for sd in ['_data', '_plots', '_detrend']:
if not os.path.exists(os.path.join(datadir, str(id), sd)):
os.makedirs(os.path.join(datadir, str(id), sd))
if not quiet:
print("Downloading TPF data...")
# Download the data
try:
obj = get_kplr_obj(id)
except:
raise Exception("Unable to access online database.")
data = EmptyData(quarters)
# Target pixel files
tpf = obj.get_target_pixel_files(short_cadence=not long_cadence)
# Lightcurves
lcs = obj.get_light_curves(short_cadence=not long_cadence)
nfiles = len(tpf)
if nfiles == 0:
raise Exception("No pixel files for selected object!")
elif len(lcs) != nfiles:
# This shouldn't happen. If it does, I'll need to re-code this section
raise Exception(
"Mismatch in number of lightcurves and number of pixel files.")
# Loop over the target pixel files/lightcurve files
for fnum in range(nfiles):
with tpf[fnum].open(clobber=clobber) as f:
ap = f[2].data
qdata = f[1].data
quarter = f[0].header['QUARTER']
if quarter not in quarters:
continue
crwd = f[1].header['CROWDSAP']
with lcs[fnum].open(clobber=clobber) as f:
hdu_data = f[1].data
pdcf = np.array(hdu_data["pdcsap_flux"] -
np.nanmedian(hdu_data["pdcsap_flux"]))
pdce = np.array(hdu_data["pdcsap_flux_err"])
if aperture == 'optimal':
idx = np.where(ap & 2)
elif aperture == 'full':
idx = np.where(ap & 1)
else:
raise Exception('ERROR: Invalid aperture setting `%s`.' % aperture)
time = np.array(qdata.field('TIME'), dtype='float64')
if len(time) != len(pdcf):
# This shouldn't happen. If it does, I'll need to re-code this section
raise Exception('Mismatch in length of pixel flux and PDC flux!')
# Any NaNs will screw up the transit model calculation,
# so we need to remove them now.
nan_inds = list(np.where(np.isnan(time))[0])
time = np.delete(time, nan_inds)
cadn = np.array(qdata.field('CADENCENO'), dtype='int32')
cadn = np.delete(cadn, nan_inds)
flux = np.array(qdata.field('FLUX'), dtype='float64')
flux = np.delete(flux, nan_inds, 0)
fpix = np.array([f[idx] for f in flux], dtype='float64')
# Inject transits?
if (inject is not None) and (inject != {}) and (inject != False):
psm = ps.Transit(**inject)
tmod = (psm(time, 'binned') - 1.) * crwd + 1.
for n in range(fpix.shape[1]):
fpix[:, n] *= tmod
perr = np.array([f[idx] for f in qdata.field('FLUX_ERR')],
dtype='float64')
perr = np.delete(perr, nan_inds, 0)
pdcf = np.delete(pdcf, nan_inds, 0)
pdce = np.delete(pdce, nan_inds, 0)
# Remove bad bits
quality = qdata.field('QUALITY')
quality = np.delete(quality, nan_inds)
qual_inds = []
for b in bad_bits:
qual_inds += list(np.where(quality & 2**(b - 1))[0])
nan_inds = list(np.where(np.isnan(np.sum(fpix, axis=1)))[0])
bad_inds = np.array(sorted(list(set(qual_inds + nan_inds))))
time = np.delete(time, bad_inds)
cadn = np.delete(cadn, bad_inds)
fpix = np.delete(fpix, bad_inds, 0)
perr = np.delete(perr, bad_inds, 0)
pdcf = np.delete(pdcf, bad_inds, 0)
pdce = np.delete(pdce, bad_inds, 0)
data[quarter].update({
'time': time,
'fpix': fpix,
'perr': perr,
'cadn': cadn,
'crwd': crwd,
'pdcf': pdcf,
'pdce': pdce
})
# Save to disk
np.savez_compressed(os.path.join(datadir, str(id), '_data', 'raw.npz'),
data=data,
hash=GitHash())
# Download the info so we have it saved on disk
DownloadKeplerInfo(id,
datadir=datadir,
clobber=clobber,
ttvs=ttvs,
pad=pad,
inject=inject,
trninfo=trninfo)
return data
fig, ax = pl.subplots(5, 5, figsize=(24, 16))
fig.subplots_adjust(wspace=0,
hspace=0,
left=0.01,
right=0.99,
bottom=0.01,
top=0.99)
ax = ax.flatten()
for axis in ax:
axis.xaxis.set_ticklabels([])
axis.yaxis.set_ticklabels([])
# Different radii
time = np.linspace(-0.5, 0.5, 1000)
for RpRs in [0.1, 0.09, 0.08]:
trn = ps.Transit(RpRs=RpRs)
ax[0].plot(time, trn(time), label='RpRs = %.2f' % RpRs)
ax[0].legend(loc='lower left', fontsize=8)
ax[0].margins(0., 0.2)
ax[0].annotate('DIFFERENT RADII', xy=(0.05, 0.9), xycoords='axes fraction')
# Different periods
time = np.linspace(-0.5, 0.5, 1000)
for per in [10., 20., 30.]:
trn = ps.Transit(per=per)
ax[1].plot(time, trn(time), label='per = %.0f' % per)
ax[1].legend(loc='lower left', fontsize=8)
ax[1].margins(0., 0.2)
ax[1].annotate('DIFFERENT PERIODS',
xy=(0.05, 0.9),
xycoords='axes fraction')
def Depth(RpRs, **kwargs):
return 1 - ps.Transit(RpRs=RpRs, **kwargs)([kwargs.get('t0', 0.)])
kwargs = dict(RpRs = 0.1, b = 0.5,
ecc = 0.5, w = 0.,
MpMs = 0., rhos = 1.4,
per = 5., t0 = 0.,
q1 = 0.45, q2 = 0.3,
maxpts = 20000,
exptime = ps.KEPLONGEXP)
# Set up the plot
fig, ax = pl.subplots(2, 2, figsize = (10, 8))
fig.subplots_adjust(hspace = 0.35)
fig.suptitle('Pysyzygy Transit Model', fontsize = 18)
ax = ax.flatten()
# The transit lightcurve
trn = ps.Transit(**kwargs)
time = np.linspace(-0.15, 0.15, 1000)
ax[0].plot(time, trn(time, 'binned'), 'b-', label = 'binned')
ax[0].plot(time, trn(time, 'unbinned'), 'r-', label = 'unbinned')
ax[0].margins(0., 0.25)
ax[0].legend(loc = 'lower left', fontsize = 8)
ax[0].set_xlabel('Time (days)', fontsize = 12)
ax[0].set_ylabel('Normalized flux', fontsize = 12)
ax[0].set_title('Transit lightcurve')
# The orbit
trn = ps.Transit(fullorbit = True, **kwargs)
time = np.linspace(-5, 5, 1000)
ax[1].plot(trn(time, 'x'), trn(time, 'y'), 'k-')