def test_rsp1d_matrix_pha_zero_energy_bin():
"""What happens when the first bin starts at 0, with replacement.
Unlike test_rsp1d_delta_pha_zero_energy_bin this directly
calls Response1D to create the model.
"""
ethresh = 1.0e-5
rdata = create_non_delta_rmf()
# hack the first bin to have 0 energy
rdata.energ_lo[0] = 0.0
# PHA and ARF have different exposure ties
exposure_arf = 0.1
exposure_pha = 2.4
specresp = create_non_delta_specresp()
with warnings.catch_warnings(record=True) as ws:
warnings.simplefilter("always")
adata = create_arf(rdata.energ_lo,
rdata.energ_hi,
specresp,
exposure=exposure_arf,
ethresh=ethresh)
validate_zero_replacement(ws, 'ARF', 'user-arf', ethresh)
nchans = rdata.e_min.size
channels = np.arange(1, nchans + 1, dtype=np.int16)
counts = np.ones(nchans, dtype=np.int16)
pha = DataPHA('test-pha',
channel=channels,
counts=counts,
exposure=exposure_pha)
pha.set_rmf(rdata)
pha.set_arf(adata)
pha.set_analysis('energy')
mdl = MyPowLaw1D()
rsp = Response1D(pha)
wrapped = rsp(mdl)
# Evaluate the statistic / model. The value was calculated using
# commit a65fb94004664eab219cc09652172ffe1dad80a6 on a linux
# system (Ubuntu 17.04).
#
f = Fit(pha, wrapped)
ans = f.calc_stat()
assert ans == pytest.approx(37971.8716151947)
def test_rsp1d_matrix_pha_zero_energy_bin():
"""What happens when the first bin starts at 0, with replacement.
Unlike test_rsp1d_delta_pha_zero_energy_bin this directly
calls Response1D to create the model.
"""
ethresh = 1.0e-5
rdata = create_non_delta_rmf()
# hack the first bin to have 0 energy
rdata.energ_lo[0] = 0.0
# PHA and ARF have different exposure ties
exposure_arf = 0.1
exposure_pha = 2.4
specresp = create_non_delta_specresp()
with warnings.catch_warnings(record=True) as ws:
warnings.simplefilter("always")
adata = create_arf(rdata.energ_lo,
rdata.energ_hi,
specresp,
exposure=exposure_arf,
ethresh=ethresh)
validate_zero_replacement(ws, 'ARF', 'user-arf', ethresh)
nchans = rdata.e_min.size
channels = np.arange(1, nchans + 1, dtype=np.int16)
counts = np.ones(nchans, dtype=np.int16)
pha = DataPHA('test-pha', channel=channels, counts=counts,
exposure=exposure_pha)
pha.set_rmf(rdata)
pha.set_arf(adata)
pha.set_analysis('energy')
mdl = MyPowLaw1D()
rsp = Response1D(pha)
wrapped = rsp(mdl)
# Evaluate the statistic / model. The value was calculated using
# commit a65fb94004664eab219cc09652172ffe1dad80a6 on a linux
# system (Ubuntu 17.04).
#
f = Fit(pha, wrapped)
ans = f.calc_stat()
assert ans == pytest.approx(37971.8716151947)
mdl = Polynom1D()
mdl.c2.thaw()
report("mdl")
from sherpa.fit import Fit
f = Fit(d, mdl)
report("f")
report("f.data")
report("f.model")
dump("f.model.c2.val")
mdl.c2 = 1
dump("f.model.c2.val")
print("Starting statistic: {:.3f}".format(f.calc_stat()))
sinfo1 = f.calc_stat_info()
report("sinfo1")
d.ignore(0, 5)
sinfo2 = f.calc_stat_info()
d.notice()
dump("sinfo1.numpoints")
dump("sinfo2.numpoints")
res = f.fit()
if res.succeeded: print("Fit succeeded")
if not res.succeeded: print("**** ERRRR, the fit failed folks")
report("res.format()")
report("res")
from sherpa.stats import LeastSq
from sherpa.optmethods import NelderMead
from sherpa.fit import Fit
f = Fit(d, mdl, stat=LeastSq(), method=NelderMead())
report("print(f)")
res = f.fit()
dump("res.succeeded")
report("res.format()")
report("res")
report("mdl")
stat2 = f.calc_stat()
print("Statistic = {:.4f}".format(stat2))
from sherpa.plot import FitPlot, ResidPlot, SplitPlot
fplot = FitPlot()
mplot.prepare(d, mdl)
fplot.prepare(dplot, mplot)
splot = SplitPlot()
splot.addplot(fplot)
rplot = ResidPlot()
print("### should get a WARNING about missing errors")
rplot.prepare(d, mdl, stat=LeastSq())
rplot.plot_prefs['yerrorbars'] = False
splot.addplot(rplot)
def prepare_spectra(group, nH, add_gal, redshift):
pha = read_pha("core_spectrum.pi")
pha.set_analysis("energy")
pha.notice(0.5, 7.0)
tabs = ~pha.mask
pha.group_counts(group, tabStops=tabs)
x = pha.get_x()
x = pha.apply_filter(x, pha._middle)
y = pha.get_y(filter=True)
pha.set_analysis("energy")
model = xsphabs.abs1 * powlaw1d.srcp1
print("Fitting the spectrum")
zFlag = False
if (nH is not None) and (nH > 0.0):
if add_gal == 1:
model = xsphabs.gal * xszphabs.abs1 * powlaw1d.srcp
gal.nH = nH
freeze(gal.nH)
zFlag = True
else:
model = xsphabs.abs1 * powlaw1d.srcp1
abs1.nH = nH
freeze(abs1.nH)
else:
model = xszphabs.abs1 * powlaw1d.srcp1
zFlag = True
if zFlag is True and add_gal == 1:
# print('REDSHIFT',redshift)
abs1.redshift = redshift
freeze(abs1.redshift)
full_model = RSPModelPHA(pha.get_arf(), pha.get_rmf(), pha, pha.exposure * model)
print(full_model)
fit = Fit(pha, full_model, method=MonCar(), stat=WStat())
res = fit.fit()
print(res.format())
print(fit.est_errors())
# calculate the p-value for wstat
mplot2 = ModelPlot()
mplot2.prepare(pha, full_model)
miu = mplot2.y * pha.exposure * 0.0146
obs = y * pha.exposure * 0.0146
c, ce, cv = gof_cstat(miu, obs)
print(f"C0={c},C_e={ce},C_v={cv}")
zval = (fit.calc_stat() - ce) / np.sqrt(cv)
if zval > 0:
pval = special.erfc(zval / np.sqrt(2))
else:
pval = special.erf(abs(zval) / np.sqrt(2))
print(f"p-value for wstat = {pval}")
set_data(pha)
set_model(model)
save_chart_spectrum("core_flux_chart.dat", elow=0.5, ehigh=7.0)
# save_chart_spectrum("core_flux_chart.rdb",format='text/tsv', elow=0.5, ehigh=7.0)
save_spectrum_rdb("core_flux_chart.dat")
def prepare_spectra(nH: float,
group: int = 1,
add_gal: bool = False,
redshift: Optional[float] = None,
**kwargs) -> float:
"""
Fit the spectra using an absorbed powerlaw model using the Wstat statistic. The function also returns a p-value for the gof.
:param nH: The galactic absorption column density in units of 10^22 /cm3
:param group: The number of counts per energy bin
:param add_gal: Setting this to True would add an intrinsic abrosption column density along side the galactic one
:param redshift: The redshift to use in the fit. Only takes effect if add_gal is set to True
...
:return: Returns the p-value of the gof. The null hypothesis states that the model and the observation differ while alternate says that the model explains the data
"""
pha = read_pha("core_spectrum.pi")
pha.set_analysis("energy")
pha.notice(0.5, 7.0)
tabs = ~pha.mask
pha.group_counts(group, tabStops=tabs)
x = pha.get_x()
x = pha.apply_filter(x, pha._middle)
y = pha.get_y(filter=True)
pha.set_analysis("energy")
model = xsphabs.abs1 * powlaw1d.srcp1
print("Fitting the spectrum")
zFlag = False
if (nH is not None) and (nH > 0.0):
if add_gal == 1:
model = xsphabs.gal * xszphabs.abs1 * powlaw1d.srcp
gal.nH = nH
freeze(gal.nH)
zFlag = True
else:
model = xsphabs.abs1 * powlaw1d.srcp1
abs1.nH = nH
freeze(abs1.nH)
else:
model = xszphabs.abs1 * powlaw1d.srcp1
zFlag = True
if zFlag is True and add_gal == 1:
# print('REDSHIFT',redshift)
abs1.redshift = redshift
freeze(abs1.redshift)
full_model = RSPModelPHA(pha.get_arf(), pha.get_rmf(), pha,
pha.exposure * model)
print(full_model)
fit = Fit(pha, full_model, method=MonCar(), stat=WStat())
res = fit.fit()
print(res.format())
print(fit.est_errors())
# calculate the p-value for wstat
mplot2 = ModelPlot()
mplot2.prepare(pha, full_model)
miu = mplot2.y * pha.exposure * 0.0146
obs = y * pha.exposure * 0.0146
c, ce, cv = SpecUtils.estimate_gof_cstat(miu, obs)
#print(f"C0={c},C_e={ce},C_v={cv}")
zval = (fit.calc_stat() - ce) / np.sqrt(cv)
if zval > 0:
pval = special.erfc(zval / np.sqrt(2))
else:
pval = special.erf(abs(zval) / np.sqrt(2))
print(f"p-value for wstat = {pval}")
set_data(pha)
set_model(model)
save_chart_spectrum("core_flux_chart.dat", elow=0.5, ehigh=7.0)
# save_chart_spectrum("core_flux_chart.rdb",format='text/tsv', elow=0.5, ehigh=7.0)
SAOTraceUtils.save_spectrum_rdb("core_flux_chart.dat")
return pval
from sherpa.stats import LeastSq
from sherpa.optmethods import NelderMead
from sherpa.fit import Fit
f = Fit(d, mdl, stat=LeastSq(), method=NelderMead())
report("print(f)")
res = f.fit()
dump("res.succeeded")
report("res.format()")
report("res")
report("mdl")
stat2 = f.calc_stat()
print("Statistic = {:.4f}".format(stat2))
from sherpa.plot import FitPlot, ResidPlot, SplitPlot
fplot = FitPlot()
mplot.prepare(d, mdl)
fplot.prepare(dplot, mplot)
splot = SplitPlot()
splot.addplot(fplot)
rplot = ResidPlot()
print("### should get a WARNING about missing errors")
rplot.prepare(d, mdl, stat=LeastSq())
rplot.plot_prefs['yerrorbars'] = False
splot.addplot(rplot)
mplot = ModelPlot()
mplot.prepare(d, mdl)
plt.subplot(2, 1, 1)
mplot.plot(clearwindow=False)
plt.subplot(2, 1, 2)
dplot.plot(clearwindow=False)
plt.title('')
savefig("model_data_before_fit.png")
from sherpa.stats import Chi2
from sherpa.fit import Fit
f = Fit(d, mdl, stat=Chi2())
report("f")
print("Starting statistic: {}".format(f.calc_stat()))
fitres = f.fit()
report("fitres.format()")
print("Reduced chi square = {:.2f}".format(fitres.rstat))
mplot.prepare(d, mdl)
dplot.plot()
mplot.overplot()
savefig("model_data_fit1.png")
from sherpa.optmethods import NelderMead
f.method = NelderMead()
fitres2 = f.fit()
report("mdl")
