def fake_data(stddev, RpRs, aRs, per, inc, midtrantime, gamma1, gamma2, ecc,
argper):
#Define Times (in days) centered at mid-transit time.
expTime = 45. / (3600 * 24.
) #Set to be 1-minute, somewhat typical for observing.
Nimages = 200. #Needs to be long enough to cover entire transit w/ some baseline.
times = np.arange(start=midtrantime - expTime * Nimages / 2.,
stop=midtrantime + expTime * Nimages / 2.,
step=expTime)
#Creates Gaussian Distributed Data using numpy.random.normal function based on standard dev.
#Commented out stuff - talk to Brett about input parameters for model.
#modelParams = [RpRs,aRs,per,inc,gamma1,gamma2,ecc,argper,midtrantime]
#fake_data = oscaar.occultquad(times,modelParams) + np.random(scale=stddev,size=np.size(times))
#Uses alternate input parameters setup for occultquad.
modelParams = [
RpRs, aRs, per, inc, gamma1, gamma2, ecc, argper, midtrantime
]
perfect_data = oscaar.occultquad(times, modelParams)
random_dist = np.random.normal(scale=stddev, size=np.size(times))
fk_data = perfect_data + random_dist
return times, fk_data
def fake_data(stddev,RpRs,aRs,per,inc,midtrantime,gamma1,gamma2,ecc,argper):
'''Takes in orbital and planetary parameters and simulates data using random gaussian fluctations.
Parameters include,
stddev - standard deviation of fake data.
RpRs - fractional planetary to stellar radius
aRs - semi-major axis/stellar radii
per - orbital period (days)
inc - inclination of orbital plane (degrees)
midtrantime - mid-transit time (JD)
gamma1 - linear limb-darkening coeff.
gamma2 - quadrtic limb-darkening coeff
argper - argument of pericenter
'''
#Define Times (in days) centered at mid-transit time.
expTime = 45./(3600*24.) #Set to be 45 sec., somewhat typical for observing.
Nimages = 200. #Needs to be long enough to cover entire transit w/ some baseline.
times = np.arange(start=midtrantime-expTime*Nimages/2.,
stop=midtrantime+expTime*Nimages/2.,
step=expTime)
#Creates Gaussian Distributed Data using numpy.random.normal function based on standard dev.
#Uses alternate input parameters setup for occultquad.
modelParams=[RpRs,aRs,per,inc,gamma1,gamma2,ecc,argper,midtrantime]
perfect_data = oscaar.occultquad(times,modelParams)
random_dist = np.random.normal(scale=stddev,size=np.size(times))
fk_data = perfect_data + random_dist
return times,fk_data
def occultquadForTransiter(t,p,ap,i,t0,gamma1=fit[4],gamma2=fit[5],P=perGuess,e=eccGuess,longPericenter=0.0):
b=ap*np.cos(i)
if b > 1.0 or i > 90.0 or gamma1 < 0.0 or gamma1 > 1.0:
return np.zeros(len(t))
elif gamma2 < 0.0 or gamma2 > 1.0 or i < 75.0:
return np.zeros(len(t))
else:
modelParams = [p,ap,P,i,gamma1,gamma2,e,longPericenter,t0]
return oscaar.occultquad(t,modelParams)
def fitfunc(p,t=t,P=P,gamma1=gamma1,gamma2=gamma2,e=e,longPericenter=longPericenter):
'''Fixed parameters: P, gamma1, gamma2, e, longPericenter
Constraints: 0<=inclination<=90, but to prevent the leastsq algorithm from getting penalized
for inclinations near 90, allow it to vary over range (0,180), and if a value is submitted > 90,
then subtract it from 180 to return a value on 0=<i<90'''
if p[2] >= 0 and p[2] <= 180:
if p[2] > 90: p[2] = 180 - p[2] ## 90 - (p[2] - 90)
#occultquad(t,p[0],p[1],P,p[2],gamma1,gamma2,e,longPericenter,p[3],n,F)
modelParams = [p[0],p[1],P,p[2],gamma1,gamma2,e,longPericenter,p[3]]
F = oscaar.occultquad(times,modelParams)
return F
def occultquadForTransiter(t,
p,
ap,
i,
t0,
gamma1=0.0,
gamma2=0.0,
P=perGuess,
e=eccGuess,
longPericenter=0.0):
modelParams = [p, ap, P, i, gamma1, gamma2, e, longPericenter, t0]
return oscaar.occultquad(t, modelParams)
def fitfunc(p,
t=t,
P=P,
gamma1=gamma1,
gamma2=gamma2,
e=e,
longPericenter=longPericenter):
'''Fixed parameters: P, gamma1, gamma2, e, longPericenter
Constraints: 0<=inclination<=90, but to prevent the leastsq algorithm from getting penalized
for inclinations near 90, allow it to vary over range (0,180), and if a value is submitted > 90,
then subtract it from 180 to return a value on 0=<i<90'''
if p[2] >= 0 and p[2] <= 180:
if p[2] > 90: p[2] = 180 - p[2] ## 90 - (p[2] - 90)
#occultquad(t,p[0],p[1],P,p[2],gamma1,gamma2,e,longPericenter,p[3],n,F)
modelParams = [
p[0], p[1], P, p[2], gamma1, gamma2, e, longPericenter, p[3]
]
F = oscaar.occultquad(times, modelParams)
return F
def occultquadForTransiter(t,p,ap,i,t0,gamma1=gamma1,gamma2=gamma2,P=perGuess,e=eccGuess,longPericenter=0.0):
'''Defines oscaar.occultquad differently to be compatible w/ optimize.curve_fit
If a parameter goes outside physical boundries then it returns
an array of zeros, such that the chi squared value is extremely high.
Constraints:
Limb-darkening Coeff's -- 0.0 < gamma < 1.0
Inclination < 90 degrees
Impact Parameter < 1 (assumes no grazing transits)
'''
b=ap*np.cos(i)
if b > 1.0 or i > 90.0 or gamma1 < 0.0 or gamma1 > 1.0:
return np.zeros(len(t))
elif gamma2 < 0.0 or gamma2 > 1.0:
return np.zeros(len(t))
else:
modelParams = [p,ap,P,i,gamma1,gamma2,e,longPericenter,t0]
return oscaar.occultquad(t,modelParams)
def fake_data(stddev,RpRs,aRs,per,inc,midtrantime,gamma1,gamma2,ecc,argper):
#Define Times (in days) centered at mid-transit time.
expTime = 45./(3600*24.) #Set to be 1-minute, somewhat typical for observing.
Nimages = 200. #Needs to be long enough to cover entire transit w/ some baseline.
times = np.arange(start=midtrantime-expTime*Nimages/2.,
stop=midtrantime+expTime*Nimages/2.,
step=expTime)
#Creates Gaussian Distributed Data using numpy.random.normal function based on standard dev.
#Commented out stuff - talk to Brett about input parameters for model.
#modelParams = [RpRs,aRs,per,inc,gamma1,gamma2,ecc,argper,midtrantime]
#fake_data = oscaar.occultquad(times,modelParams) + np.random(scale=stddev,size=np.size(times))
#Uses alternate input parameters setup for occultquad.
modelParams=[RpRs,aRs,per,inc,gamma1,gamma2,ecc,argper,midtrantime]
perfect_data = oscaar.occultquad(times,modelParams)
random_dist = np.random.normal(scale=stddev,size=np.size(times))
fk_data = perfect_data + random_dist
return times,fk_data
from matplotlib import pyplot as plt
from scipy import optimize
import oscaar
## If you've run sampleMCMC.py before and want to load the results of that
## run, set loadvals = True. To run a fresh chain, set loadvals = False.
loadvals = False
if loadvals == False:
##############################
# Generate sample transit light curve with random Gaussian noise
x = np.arange(0.1, 0.4, 2e-3)
noiseFactor = 5.0e-3 ## Set how much noise is added
modelParams = [0.11, 4.1, 2.2, 83.1, 0.23, 0.3, 0.0, 0.0,
0.25] ## Set simulated planet's parameters
y = oscaar.occultquad(
x, modelParams) + np.random.normal(0, 1, x.shape) * noiseFactor
sigma_y = np.zeros_like(x) + noiseFactor
Npoints = len(x)
plt.errorbar(x, y, yerr=sigma_y) ## Plot the simulated light curve
plt.show()
##############################
# Fit with MCMC
Nsteps = int(
0.75e6) ## Number of MCMC "links in the chain" / number of steps
saveInterval = 1e3 ## interval between MCMC links that get saved for uncertainty estimation
inputParams = np.array([0.12, 3.9, 83.0, 0.26],
dtype=np.float64) ## Initial fit parameters
## Parameters: [Rp/Rs, a/Rs, inclination, mid-transit time]
import numpy as np
from matplotlib import pyplot as plt
from scipy import optimize
import oscaar
## If you've run sampleMCMC.py before and want to load the results of that
## run, set loadvals = True. To run a fresh chain, set loadvals = False.
loadvals = False
if loadvals == False:
##############################
# Generate sample transit light curve with random Gaussian noise
x = np.arange(0.1,0.4,2e-3)
noiseFactor = 5.0e-3 ## Set how much noise is added
modelParams = [0.11,4.1,2.2,83.1,0.23,0.3,0.0,0.0,0.25] ## Set simulated planet's parameters
y = oscaar.occultquad(x,modelParams) + np.random.normal(0,1,x.shape)*noiseFactor
sigma_y = np.zeros_like(x) + noiseFactor
Npoints = len(x)
plt.errorbar(x,y,yerr=sigma_y) ## Plot the simulated light curve
plt.show()
##############################
# Fit with MCMC
Nsteps = int(0.75e6) ## Number of MCMC "links in the chain" / number of steps
saveInterval = 1e3 ## interval between MCMC links that get saved for uncertainty estimation
inputParams = np.array([0.12,3.9,83.0,0.26],dtype=np.float64) ## Initial fit parameters
## Parameters: [Rp/Rs, a/Rs, inclination, mid-transit time]
def occult4params(t,params):
'''Allow 4 parameters to vary freely, keep the others fixed at the values assigned below'''
def main():
#################################################################
## Tweak these parameters, if you like!
NdataImages = 200 ## Number of data images to generate
NdarkImages = 3 ## Number of dark frames to generate
NflatImages = 3 ## Number of flat fields to generate
flatFieldCounts = 20000 ## Approx counts per pixel in flat field
imageDimensionX = 120 ## Pixel dimensions of each image
imageDimensionY = 40
starDimensions = 4 ## Pixel dimensions of the stars
skyBackground = 500 ## Background counts from sky brightness
darkBackground = 100 ## Background counts from detector
targetFluxOOT = 10000 ## Flux (in counts) from each pixel of the unocculted target star (out-of-transit)
relativeFluxCompA = 0.85 ## Flux from comp A relative to target
relativeFluxCompB = 0.95 ## Flux from comp B relative to target
plotModel = False ## Plot the injected transit light curve
createMasterFlatNow = True ## Use oscaar to create a master flat from the freshly generated flat frames
## Isn't it nice to control the signal to noise?
#################################################################
## Delete `images` directory, if there is one, and
## make a fresh one.
if len(glob(os.path.join(os.path.dirname(__file__),'images'))) > 0: rmtree(os.path.join(os.path.dirname(__file__),'images'))
mkdir(os.path.join(os.path.dirname(__file__),'images'))
## Pixel positions of the stars (x,y)
targetX = [20-starDimensions/2,20+starDimensions/2]
compAX = [60-starDimensions/2,60+starDimensions/2]
compBX = [100-starDimensions/2,100+starDimensions/2]
starsY = [imageDimensionY/2-starDimensions/2,imageDimensionY/2+starDimensions/2]
## Set ingress/egress times, transiting system parameters
## In GD: Ingress = 2013-05-15;10:06:30; egress = 2013-05-15;11:02:35
jd0 = 2456427.88890
exposureTime = 45/(60*60*24.) ## Convert s -> hr
times = np.arange(jd0,jd0+exposureTime*NdataImages,exposureTime)
# [p,ap,P,i,gamma1,gamma2,e,longPericenter,t0]
modelParams = [ 0.1179, 14.71, 1.580400, 90.0, 0.23, \
0.30, 0.00, 0.0, np.mean(times,dtype=np.float64)]
np.savetxt(os.path.join(os.path.dirname(__file__),'modelParams.txt'),modelParams)
modelLightCurve = oscaar.occultquad(times,modelParams)
if plotModel:
fig = plt.figure()
ax1 = fig.add_subplot(111)
def format_coord(x, y):
'''Function to also give data value on mouse over with imshow.'''
return 'JD=%1.6f, Flux=%1.6f' % (x, y)
ax1.set_xlabel('Time (JD)')
ax1.set_ylabel('Relative Flux')
ax1.set_title('Injected Light Curve')
ax1.plot(times,modelLightCurve)
ax1.format_coord = format_coord
plt.show()
## For producing random arrays, initialize reference arrays with the proper shapes
imageShapedMatrix = np.zeros([imageDimensionY,imageDimensionX])
starShapedMatrix = np.zeros([starDimensions,starDimensions])
## Simulate dark frames with shot noise
for i in range(NdarkImages):
darkFrame = darkBackground + np.random.normal(imageShapedMatrix,np.sqrt(darkBackground))
darkFrame = np.require(darkFrame,dtype=int) ## Require integer counts
pyfits.writeto(os.path.join(os.path.dirname(__file__),'images/simulatedImg-'+str(i).zfill(3)+'d.fits'),darkFrame)
## Simulate ideal flat frames (perfectly flat)
for i in range(NflatImages):
## Flats will be completely flat -- ie, we're pretending that we have a
## perfect optical path with no spatial flux variations.
flatField = np.zeros([imageDimensionY,imageDimensionX]) + flatFieldCounts
flatField = np.require(flatField,dtype=int)## Require integer counts
pyfits.writeto(os.path.join(os.path.dirname(__file__),'images/simulatedImg-'+str(i).zfill(3)+'f.fits'),flatField)
## Create master flat now using oscaar's standard flat maker
if createMasterFlatNow:
flatPaths = glob(os.path.join(os.path.dirname(__file__),'images/simulatedImg-???f.fits'))
flatDarkPaths = glob(os.path.join(os.path.dirname(__file__),'images/simulatedImg-???d.fits')) ## Use the same darks
masterFlatSavePath = os.path.join(os.path.dirname(__file__),'images/masterFlat.fits') ## Where to save the master
oscaar.standardFlatMaker(flatPaths,flatDarkPaths,masterFlatSavePath,plots=False)
## Create data images
for i in range(NdataImages):
## Produce image with sky and dark background with simulated photon noise for each source
simulatedImage = darkBackground + skyBackground +\
np.random.normal(imageShapedMatrix,np.sqrt(darkBackground)) +\
np.random.normal(imageShapedMatrix,np.sqrt(skyBackground))
## Create two box-shaped stars with simulated photon noise
targetBrightness = targetFluxOOT*modelLightCurve[i] ## Scale brightness with the light curve
target = targetBrightness + np.random.normal(starShapedMatrix,np.sqrt(targetBrightness))
compBrightnessA = targetFluxOOT*relativeFluxCompA
compBrightnessB = targetFluxOOT*relativeFluxCompB
compA = compBrightnessA + np.random.normal(starShapedMatrix,np.sqrt(compBrightnessA))
compB = compBrightnessB + np.random.normal(starShapedMatrix,np.sqrt(compBrightnessB))
## Add stars onto the simulated image with some position jitter
randomPositionJitterX = np.sign(np.random.uniform(-1,1)) ## +/- 1 pixel stellar centroid position jitter
randomPositionJitterY = np.sign(np.random.uniform(-1,1)) ## +/- 1 pixel stellar centroid position jitter
simulatedImage[starsY[0]+randomPositionJitterY:starsY[1]+randomPositionJitterY,targetX[0]+randomPositionJitterX:targetX[1]+randomPositionJitterX] += target
simulatedImage[starsY[0]+randomPositionJitterY:starsY[1]+randomPositionJitterY,compAX[0]+randomPositionJitterX:compAX[1]+randomPositionJitterX] += compA
simulatedImage[starsY[0]+randomPositionJitterY:starsY[1]+randomPositionJitterY,compBX[0]+randomPositionJitterX:compBX[1]+randomPositionJitterX] += compB
## Force counts to integers, save.
simulatedImage = np.require(simulatedImage,dtype=int) ## Require integer counts before save
header = pyfits.Header()
header.append(('JD',times[i],'Simulated Time (Julian Date)'))
pyfits.writeto(os.path.join(os.path.dirname(__file__),'images/simulatedImg-'+str(i).zfill(3)+'r.fits'),simulatedImage,header=header)
lib_path = os.path.abspath('../../Code/')
sys.path.append(lib_path)
import oscaar
## Define system parameters for planet HAT-P-7 b.
## Citation: Morris et al. 2013 (http://arxiv.org/abs/1301.4503)
RpOverRs = 0.07759 ## R_p/R_s = ratio of planetary radius to stellar radius
aOverRs = 4.0 ## a/R_s = ratio of semimajor axis to stellar radius
period = 2.204737 ## Period [days]
inclination = 83.111 ## Inclination [degrees]
gamma1 = 0.3525 ## Linear limb-darkening coefficient
gamma2 = 0.168 ## Quadratic limb-darkening coefficient
eccentricity = 0.0 ## Eccentricity
longPericenter = 0.0 ## Longitude of pericenter
epoch = 2454954.357463 ## Mid transit time [Julian date]
## Generate times at which to calculate the flux
durationOfObservation = 6./24 ## Elapsed time [days]
times = np.arange(epoch-durationOfObservation/2,epoch+durationOfObservation/2,1e-5)
modelParams = [RpOverRs,aOverRs,period,inclination,gamma1,gamma2,eccentricity,longPericenter,epoch]
## Generate light curve
flux = oscaar.occultquad(times,modelParams)
## Plot light curve
plt.plot(times,flux,linewidth=2)
plt.title('Transit light curve for HAT-P-7 b')
plt.ylabel('Relative Flux')
plt.xlabel('Time (JD)')
plt.show()
def occultquadForTransiter(t,p,ap,i,t0,gamma1=0.0,gamma2=0.0,P=perGuess,e=eccGuess,longPericenter=0.0):
modelParams = [p,ap,P,i,gamma1,gamma2,e,longPericenter,t0]
return oscaar.occultquad(t,modelParams)
def occult4params(t, params):
'''Allow 4 parameters to vary freely, keep the others fixed at the values assigned below'''
p, ap, i, t0 = params
return oscaar.occultquad(t, [p, ap, 2.2, i, 0.23, 0.3, 0.0, 0.0, t0])
## Define system parameters for planet HAT-P-7 b.
## Citation: Morris et al. 2013 (http://arxiv.org/abs/1301.4503)
RpOverRs = 0.07759 ## R_p/R_s = ratio of planetary radius to stellar radius
aOverRs = 4.0 ## a/R_s = ratio of semimajor axis to stellar radius
period = 2.204737 ## Period [days]
inclination = 83.111 ## Inclination [degrees]
gamma1 = 0.3525 ## Linear limb-darkening coefficient
gamma2 = 0.168 ## Quadratic limb-darkening coefficient
eccentricity = 0.0 ## Eccentricity
longPericenter = 0.0 ## Longitude of pericenter
epoch = 2454954.357463 ## Mid transit time [Julian date]
## Generate times at which to calculate the flux
durationOfObservation = 6. / 24 ## Elapsed time [days]
times = np.arange(epoch - durationOfObservation / 2,
epoch + durationOfObservation / 2, 1e-5)
modelParams = [
RpOverRs, aOverRs, period, inclination, gamma1, gamma2, eccentricity,
longPericenter, epoch
]
## Generate light curve
flux = oscaar.occultquad(times, modelParams)
## Plot light curve
plt.plot(times, flux, linewidth=2)
plt.title('Transit light curve for HAT-P-7 b')
plt.ylabel('Relative Flux')
plt.xlabel('Time (JD)')
plt.show()
def occult4params(t,params):
'''Allow 4 parameters to vary freely, keep the others fixed at the values assigned below'''
p,ap,i,t0 = params
return oscaar.occultquad(t,[p,ap,2.2,i,0.23,0.3,0.0,0.0,t0])
def main():
#################################################################
## Tweak these parameters, if you like!
NdataImages = 200 ## Number of data images to generate
NdarkImages = 3 ## Number of dark frames to generate
NflatImages = 3 ## Number of flat fields to generate
flatFieldCounts = 20000 ## Approx counts per pixel in flat field
imageDimensionX = 120 ## Pixel dimensions of each image
imageDimensionY = 40
starDimensions = 4 ## Pixel dimensions of the stars
skyBackground = 500 ## Background counts from sky brightness
darkBackground = 100 ## Background counts from detector
targetFluxOOT = 10000 ## Flux (in counts) from each pixel of the unocculted target star (out-of-transit)
relativeFluxCompA = 0.85 ## Flux from comp A relative to target
relativeFluxCompB = 0.95 ## Flux from comp B relative to target
plotModel = False ## Plot the injected transit light curve
createMasterFlatNow = True ## Use oscaar to create a master flat from the freshly generated flat frames
## Isn't it nice to control the signal to noise?
#################################################################
## Delete `images` directory, if there is one, and
## make a fresh one.
if len(glob(os.path.join(os.path.dirname(__file__), 'images'))) > 0:
rmtree(os.path.join(os.path.dirname(__file__), 'images'))
mkdir(os.path.join(os.path.dirname(__file__), 'images'))
## Pixel positions of the stars (x,y)
targetX = [20 - starDimensions / 2, 20 + starDimensions / 2]
compAX = [60 - starDimensions / 2, 60 + starDimensions / 2]
compBX = [100 - starDimensions / 2, 100 + starDimensions / 2]
starsY = [
imageDimensionY / 2 - starDimensions / 2,
imageDimensionY / 2 + starDimensions / 2
]
## Set ingress/egress times, transiting system parameters
## In GD: Ingress = 2013-05-15;10:06:30; egress = 2013-05-15;11:02:35
jd0 = 2456427.88890
exposureTime = 45 / (60 * 60 * 24.) ## Convert s -> hr
times = np.arange(jd0, jd0 + exposureTime * NdataImages, exposureTime)
# [p,ap,P,i,gamma1,gamma2,e,longPericenter,t0]
modelParams = [ 0.1179, 14.71, 1.580400, 90.0, 0.23, \
0.30, 0.00, 0.0, np.mean(times,dtype=np.float64)]
np.savetxt(os.path.join(os.path.dirname(__file__), 'modelParams.txt'),
modelParams)
modelLightCurve = oscaar.occultquad(times, modelParams)
if plotModel:
fig = plt.figure()
ax1 = fig.add_subplot(111)
def format_coord(x, y):
'''Function to also give data value on mouse over with imshow.'''
return 'JD=%1.6f, Flux=%1.6f' % (x, y)
ax1.set_xlabel('Time (JD)')
ax1.set_ylabel('Relative Flux')
ax1.set_title('Injected Light Curve')
ax1.plot(times, modelLightCurve)
ax1.format_coord = format_coord
plt.show()
## For producing random arrays, initialize reference arrays with the proper shapes
imageShapedMatrix = np.zeros([imageDimensionY, imageDimensionX])
starShapedMatrix = np.zeros([starDimensions, starDimensions])
## Simulate dark frames with shot noise
for i in range(NdarkImages):
darkFrame = darkBackground + np.random.normal(imageShapedMatrix,
np.sqrt(darkBackground))
darkFrame = np.require(darkFrame, dtype=int) ## Require integer counts
pyfits.writeto(
os.path.join(os.path.dirname(__file__),
'images/simulatedImg-' + str(i).zfill(3) + 'd.fits'),
darkFrame)
## Simulate ideal flat frames (perfectly flat)
for i in range(NflatImages):
## Flats will be completely flat -- ie, we're pretending that we have a
## perfect optical path with no spatial flux variations.
flatField = np.zeros([imageDimensionY, imageDimensionX
]) + flatFieldCounts
flatField = np.require(flatField, dtype=int) ## Require integer counts
pyfits.writeto(
os.path.join(os.path.dirname(__file__),
'images/simulatedImg-' + str(i).zfill(3) + 'f.fits'),
flatField)
## Create master flat now using oscaar's standard flat maker
if createMasterFlatNow:
flatPaths = glob(
os.path.join(os.path.dirname(__file__),
'images/simulatedImg-???f.fits'))
flatDarkPaths = glob(
os.path.join(
os.path.dirname(__file__),
'images/simulatedImg-???d.fits')) ## Use the same darks
masterFlatSavePath = os.path.join(
os.path.dirname(__file__),
'images/masterFlat.fits') ## Where to save the master
oscaar.standardFlatMaker(flatPaths,
flatDarkPaths,
masterFlatSavePath,
plots=False)
## Create data images
for i in range(NdataImages):
## Produce image with sky and dark background with simulated photon noise for each source
simulatedImage = darkBackground + skyBackground +\
np.random.normal(imageShapedMatrix,np.sqrt(darkBackground)) +\
np.random.normal(imageShapedMatrix,np.sqrt(skyBackground))
## Create two box-shaped stars with simulated photon noise
targetBrightness = targetFluxOOT * modelLightCurve[
i] ## Scale brightness with the light curve
target = targetBrightness + np.random.normal(starShapedMatrix,
np.sqrt(targetBrightness))
compBrightnessA = targetFluxOOT * relativeFluxCompA
compBrightnessB = targetFluxOOT * relativeFluxCompB
compA = compBrightnessA + np.random.normal(starShapedMatrix,
np.sqrt(compBrightnessA))
compB = compBrightnessB + np.random.normal(starShapedMatrix,
np.sqrt(compBrightnessB))
## Add stars onto the simulated image with some position jitter
randomPositionJitterX = np.sign(np.random.uniform(
-1, 1)) ## +/- 1 pixel stellar centroid position jitter
randomPositionJitterY = np.sign(np.random.uniform(
-1, 1)) ## +/- 1 pixel stellar centroid position jitter
simulatedImage[starsY[0] + randomPositionJitterY:starsY[1] +
randomPositionJitterY,
targetX[0] + randomPositionJitterX:targetX[1] +
randomPositionJitterX] += target
simulatedImage[starsY[0] + randomPositionJitterY:starsY[1] +
randomPositionJitterY,
compAX[0] + randomPositionJitterX:compAX[1] +
randomPositionJitterX] += compA
simulatedImage[starsY[0] + randomPositionJitterY:starsY[1] +
randomPositionJitterY,
compBX[0] + randomPositionJitterX:compBX[1] +
randomPositionJitterX] += compB
## Force counts to integers, save.
simulatedImage = np.require(
simulatedImage, dtype=int) ## Require integer counts before save
header = pyfits.Header()
header.append(('JD', times[i], 'Simulated Time (Julian Date)'))
pyfits.writeto(os.path.join(
os.path.dirname(__file__),
'images/simulatedImg-' + str(i).zfill(3) + 'r.fits'),
simulatedImage,
header=header)