def generate(ngen,
surveyList=None,
age_max=1.0E9,
pDistPars=[.3, .15],
bFieldPars=[12.65, 0.55],
birthVPars=[0.0, 180.],
siDistPars= [-1.6,0.35],
alignModel='orthogonal',
lumDistType='fk06',
lumDistPars=[-1.5, 0.5],
alignTime=None,
spinModel = 'fk06',
beamModel = 'tm98',
birthVModel = 'gaussian',
electronModel='ne2001',
braking_index=0,
zscale=0.33,
duty=5.,
nodeathline=False,
nostdout=False,
nospiralarms=False):
pop = Population()
# set the parameters in the population object
pop.pmean, pop.psigma = pDistPars
pop.bmean, pop.bsigma = bFieldPars
if lumDistType=='pow':
try:
pop.lummin, pop.lummax, pop.lumpow = \
lumDistPars[0], lumDistPars[1], lumDistPars[2]
except ValueError:
raise EvolveException('Not enough lum distn parameters')
else:
pop.lumPar1, pop.lumPar2 = lumDistPars
pop.simean, pop.sisigma = siDistPars
pop.birthvmean, pop.birthvsigma = birthVPars
pop.alignModel = alignModel
pop.alignTime= alignTime
pop.spinModel = spinModel
pop.beamModel = beamModel
pop.birthVModel = birthVModel
pop.electronModel = electronModel
pop.braking_index = braking_index
pop.nodeathline = nodeathline
pop.nospiralarms = nospiralarms
pop.zscale = zscale
if not nostdout:
print "\tGenerating evolved pulsars with parameters:"
print "\t\tngen = {0}".format(ngen)
print "\t\tUsing electron distn model {0}".format(
pop.electronModel)
print "\n\t\tPeriod mean, sigma = {0}, {1}".format(
pop.pmean,
pop.psigma)
print "\t\tLuminosity mean, sigma = {0}, {1}".format(
pop.lummean,
pop.lumsigma)
print "\t\tSpectral index mean, sigma = {0}, {1}".format(
pop.simean,
pop.sisigma)
print "\t\tGalactic z scale height = {0} kpc".format(
pop.zscale)
print "\t\tWidth {0}% ".format(duty)
# set up progress bar for fun :)
prog = ProgressBar(min_value = 0,
max_value=ngen,
width=65,
mode='dynamic')
# create survey objects here and put them in a list
if surveyList is not None:
surveys = [Survey(s) for s in surveyList]
else:
# make an empty list here - makes some code just a little
# simpler - can still loop over an empty list (ie zero times)
surveys=[]
# initialise these counters to zero
for surv in surveys:
surv.ndet =0 # number detected
surv.nout=0 # number outside survey region
surv.nsmear=0 # number smeared out
surv.ntf=0 # number too faint
# this is the nitty-gritty loop for generating the pulsars
while pop.ndet < ngen:
pulsar = Pulsar()
# initial age for pulsar
pulsar.age = random.random() * age_max
# initial period
pulsar.p0 = -1.
while pulsar.p0 <= 0.:
pulsar.p0 = random.gauss(pop.pmean, pop.psigma)
# initial magnetic field (in Gauss)
pulsar.bfield_init = 10**random.gauss(pop.bmean, pop.bsigma)
# aligment angle
alignpulsar(pulsar, pop)
# braking index
if pop.braking_index == 0:
pulsar.braking_index = 2.5 + 0.5 * random.random()
else:
pulsar.braking_index = float(pop.braking_index)
#apply relevant spin down model
pulsar.dead = False # pulsar should start alive!
if pop.spinModel == 'fk06':
spindown_fk06(pulsar)
# apply deathline if relevant
if not pop.nodeathline:
bhattacharya_deathperiod_92(pulsar)
elif pop.spinModel == 'cs06':
# contopoulos and spitkovsky
spindown_cs06(pulsar, pop)
# define pulse width (default = 5% = 18 degrees)
pulsar.width_degree = 360. * duty /100.
# plough on - only if the pulsar isn't dead!
if not pulsar.dead:
# is the pulsar beaming?
pulsar_beaming(pulsar, pop.beamModel)
# if not, then skip onto next pulsar
if not pulsar.beaming:
continue
# position of the pulsar
galacticDistribute(pulsar, pop)
# birthvelocity
birthVelocity(pulsar, pop)
# model the xyz velocity
go.vxyz(pulsar)
# luminosity
if lumDistType == 'fk06':
luminosity_fk06(pulsar, alpha=pop.lumPar1, beta=pop.lumPar2)
elif lumDistType == 'lnorm':
pulsar.lum_1400 = populate._drawlnorm(pop.lumPar1, pop.lumPar2)
elif lumDistType == 'pow':
pulsar.lum_1400 = populate._powerlaw(pop.lummin,
pop.lummax,
pop.lumpow)
else:
# something's wrong!
raise EvolveException('Invalid luminosity distn selected')
# spectral index
pulsar.spindex = random.gauss(pop.simean, pop.sisigma)
# calculate galactic coords and distance
pulsar.gl, pulsar.gb = go.xyz_to_lb(pulsar.galCoords)
pulsar.dtrue = go.calc_dtrue(pulsar.galCoords)
# then calc DM using fortran libs
if pop.electronModel == 'ne2001':
pulsar.dm = go.ne2001_dist_to_dm(pulsar.dtrue,
pulsar.gl,
pulsar.gb)
elif pop.electronModel == 'lmt85':
pulsar.dm = go.lmt85_dist_to_dm(pulsar.dtrue,
pulsar.gl,
pulsar.gb)
# if surveys are given, check if pulsar detected or not
# in ANY of the surveys
if surveyList is not None:
detect_int = 0 # just a flag if pulsar is detected
for surv in surveys:
SNR = surv.SNRcalc(pulsar, pop)
if SNR > surv.SNRlimit:
# SNR is over threshold
# increment the flag
# and survey ndetected
detect_int += 1
surv.ndet += 1
continue
elif SNR == -1:
# pulse is smeared out
surv.nsmear += 1
continue
elif SNR == -2:
# pulsar is outside survey region
surv.nout += 1
continue
else:
#pulsar is just too faint
surv.ntf += 1
continue
# if detected, increment ndet (for whole population)
# and redraw the progress bar
if detect_int:
pop.ndet += 1
# update the counter
if not nostdout:
prog.increment_amount()
print prog, '\r',
sys.stdout.flush()
else:
# no survey list, just add the pulsar to population,
# and increment number of pulsars
pop.ndet +=1
# update the counter
if not nostdout:
prog.increment_amount()
print prog, '\r',
sys.stdout.flush()
# pulsar isn't dead, add to population!
pop.population.append(pulsar)
else:
# pulsar is dead. If no survey list,
# just increment number of pulsars
if surveyList is None:
pop.ndet += 1
# update the counter
if not nostdout:
prog.increment_amount()
print prog, '\r',
sys.stdout.flush()
if not nostdout:
print "\n\n"
print " Total pulsars = {0}".format(len(pop.population))
print " Total detected = {0}".format(pop.ndet)
for surv in surveys:
print "\n Results for survey '{0}'".format(surv.surveyName)
print " Number detected = {0}".format(surv.ndet)
print " Number too faint = {0}".format(surv.ntf)
print " Number smeared = {0}".format(surv.nsmear)
print " Number outside survey area = {0}".format(surv.nout)
return pop
