Commit 39a5aa700397234982b228c1ed353e80986e50f5
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9c5ea323
Add event simulation example script and test XML file
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examples/model_bgd.xml
0 → 100644
| 1 | +<?xml version="1.0" standalone="no"?> | ||
| 2 | +<source_library title="source library"> | ||
| 3 | + <source name="Background" type="RadialAcceptance" instrument="CTA"> | ||
| 4 | + <spectrum type="FileFunction" file="$CTOOLS/share/models/bkg_dummy.txt"> | ||
| 5 | + <parameter scale="1.0" name="Normalization" min="0.0" max="1000.0" value="1.0" free="1"/> | ||
| 6 | + </spectrum> | ||
| 7 | + <radialModel type="Gaussian"> | ||
| 8 | + <parameter name="Sigma" scale="1.0" value="3.0" min="0.01" max="10.0" free="1"/> | ||
| 9 | + </radialModel> | ||
| 10 | + </source> | ||
| 11 | +</source_library> | ||
| 12 | + |
examples/simulate_events.py
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| 1 | +#! /usr/bin/env python | ||
| 2 | +# ========================================================================== | ||
| 3 | +# This script simulates events from a data-space model and compares them to | ||
| 4 | +# the model. | ||
| 5 | +# | ||
| 6 | +# If matplotlib is installed, the event spectrum will be displayed. | ||
| 7 | +# | ||
| 8 | +# -------------------------------------------------------------------------- | ||
| 9 | +# | ||
| 10 | +# Copyright (C) 2014 Juergen Knoedlseder | ||
| 11 | +# | ||
| 12 | +# This program is free software: you can redistribute it and/or modify | ||
| 13 | +# it under the terms of the GNU General Public License as published by | ||
| 14 | +# the Free Software Foundation, either version 3 of the License, or | ||
| 15 | +# (at your option) any later version. | ||
| 16 | +# | ||
| 17 | +# This program is distributed in the hope that it will be useful, | ||
| 18 | +# but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 19 | +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 20 | +# GNU General Public License for more details. | ||
| 21 | +# | ||
| 22 | +# You should have received a copy of the GNU General Public License | ||
| 23 | +# along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
| 24 | +# | ||
| 25 | +# ========================================================================== | ||
| 26 | +import gammalib | ||
| 27 | +import ctools | ||
| 28 | +import math | ||
| 29 | +try: | ||
| 30 | + import matplotlib.pyplot as plt | ||
| 31 | + has_matplotlib = True | ||
| 32 | +except: | ||
| 33 | + has_matplotlib = False | ||
| 34 | + | ||
| 35 | + | ||
| 36 | +# ======================== # | ||
| 37 | +# Create CTA observation # | ||
| 38 | +# ======================== # | ||
| 39 | +def createobs(ra=86.171648, dec=-1.4774586, rad=5.0, \ | ||
| 40 | + emin=0.1, emax=100.0, duration=360000.0, deadc=0.95, \ | ||
| 41 | + irf="cta_dummy_irf", caldb="$CTOOLS/share/caldb/data/cta/dummy"): | ||
| 42 | + """ | ||
| 43 | + Create CTA observation. | ||
| 44 | + """ | ||
| 45 | + # Allocate CTA observation | ||
| 46 | + obs = gammalib.GCTAObservation() | ||
| 47 | + | ||
| 48 | + # Set calibration database | ||
| 49 | + db = gammalib.GCaldb() | ||
| 50 | + if (gammalib.dir_exists(caldb)): | ||
| 51 | + db.rootdir(caldb) | ||
| 52 | + else: | ||
| 53 | + db.open("cta", caldb) | ||
| 54 | + | ||
| 55 | + # Set pointing direction | ||
| 56 | + pntdir = gammalib.GSkyDir() | ||
| 57 | + pntdir.radec_deg(ra, dec) | ||
| 58 | + pnt = gammalib.GCTAPointing() | ||
| 59 | + pnt.dir(pntdir) | ||
| 60 | + obs.pointing(pnt) | ||
| 61 | + | ||
| 62 | + # Set ROI | ||
| 63 | + roi = gammalib.GCTARoi() | ||
| 64 | + instdir = gammalib.GCTAInstDir() | ||
| 65 | + instdir.dir(pntdir) | ||
| 66 | + roi.centre(instdir) | ||
| 67 | + roi.radius(rad) | ||
| 68 | + | ||
| 69 | + # Set GTI | ||
| 70 | + gti = gammalib.GGti() | ||
| 71 | + start = gammalib.GTime(0.0) | ||
| 72 | + stop = gammalib.GTime(duration) | ||
| 73 | + gti.append(start, stop) | ||
| 74 | + | ||
| 75 | + # Set energy boundaries | ||
| 76 | + ebounds = gammalib.GEbounds() | ||
| 77 | + e_min = gammalib.GEnergy() | ||
| 78 | + e_max = gammalib.GEnergy() | ||
| 79 | + e_min.TeV(emin) | ||
| 80 | + e_max.TeV(emax) | ||
| 81 | + ebounds.append(e_min, e_max) | ||
| 82 | + | ||
| 83 | + # Allocate event list | ||
| 84 | + events = gammalib.GCTAEventList() | ||
| 85 | + events.roi(roi) | ||
| 86 | + events.gti(gti) | ||
| 87 | + events.ebounds(ebounds) | ||
| 88 | + obs.events(events) | ||
| 89 | + | ||
| 90 | + # Set instrument response | ||
| 91 | + obs.response(irf, db) | ||
| 92 | + | ||
| 93 | + # Set ontime, livetime, and deadtime correction factor | ||
| 94 | + obs.ontime(duration) | ||
| 95 | + obs.livetime(duration*deadc) | ||
| 96 | + obs.deadc(deadc) | ||
| 97 | + | ||
| 98 | + # Return observation | ||
| 99 | + return obs | ||
| 100 | + | ||
| 101 | + | ||
| 102 | +# =============== # | ||
| 103 | +# Simulate events # | ||
| 104 | +# =============== # | ||
| 105 | +def simulate(obs, xmlname): | ||
| 106 | + """ | ||
| 107 | + Simulate events. | ||
| 108 | + """ | ||
| 109 | + # Allocate random number generator | ||
| 110 | + ran = gammalib.GRan() | ||
| 111 | + | ||
| 112 | + # Load models and extract first model | ||
| 113 | + models = gammalib.GModels(xmlname) | ||
| 114 | + model = models[0] | ||
| 115 | + print(model) | ||
| 116 | + | ||
| 117 | + # Simulate events | ||
| 118 | + events = model.mc(obs, ran) | ||
| 119 | + | ||
| 120 | + # Print event statistics | ||
| 121 | + npred = obs.npred(models) | ||
| 122 | + print(str(len(events)) + " events simulated.") | ||
| 123 | + print(str(npred) + " events expected from Npred.") | ||
| 124 | + | ||
| 125 | + # Check distance | ||
| 126 | + pntdir = obs.pointing().dir() | ||
| 127 | + for event in events: | ||
| 128 | + distance = gammalib.GCTAInstDir(event.dir()).dir().dist_deg(pntdir) | ||
| 129 | + if (distance > 5.0): | ||
| 130 | + print("Too far: "+str(distance)) | ||
| 131 | + | ||
| 132 | + # Return events | ||
| 133 | + return events | ||
| 134 | + | ||
| 135 | + | ||
| 136 | +# ============================== # | ||
| 137 | +# Simulate events using ctobssim # | ||
| 138 | +# ============================== # | ||
| 139 | +def simulate_ctobssim(obs, xmlname, seed=0): | ||
| 140 | + """ | ||
| 141 | + Simulate events using ctobssim. | ||
| 142 | + """ | ||
| 143 | + # Create containers | ||
| 144 | + observations = gammalib.GObservations() | ||
| 145 | + observations.append(obs) | ||
| 146 | + | ||
| 147 | + # Append models | ||
| 148 | + models = gammalib.GModels(xmlname) | ||
| 149 | + observations.models(models) | ||
| 150 | + print(models[0]) | ||
| 151 | + | ||
| 152 | + # Allocate ctobssim application and set parameters | ||
| 153 | + sim = ctools.ctobssim(observations) | ||
| 154 | + sim['seed'].integer(seed) | ||
| 155 | + | ||
| 156 | + # Run simulator | ||
| 157 | + sim.run() | ||
| 158 | + | ||
| 159 | + # Retrieve events | ||
| 160 | + events = sim.obs()[0].events().copy() | ||
| 161 | + | ||
| 162 | + # Print event statistics | ||
| 163 | + npred = obs.npred(models) | ||
| 164 | + print(str(len(events)) + " events simulated.") | ||
| 165 | + print(str(npred) + " events expected from Npred.") | ||
| 166 | + | ||
| 167 | + # Delete the simulation | ||
| 168 | + del sim | ||
| 169 | + | ||
| 170 | + # Return events | ||
| 171 | + return events | ||
| 172 | + | ||
| 173 | + | ||
| 174 | +# =========== # | ||
| 175 | +# Show events # | ||
| 176 | +# =========== # | ||
| 177 | +def show_events(events, xmlname, duration, emin, emax, ebins=30): | ||
| 178 | + """ | ||
| 179 | + Show events using matplotlib. | ||
| 180 | + """ | ||
| 181 | + # Create figure | ||
| 182 | + plt.figure(1) | ||
| 183 | + plt.title("MC simulated event spectrum (" + str(emin) + '-' + str(emax) + " TeV)") | ||
| 184 | + | ||
| 185 | + # Setup energy range covered by data | ||
| 186 | + ebds = gammalib.GEbounds(ebins, gammalib.GEnergy(emin, "TeV"), | ||
| 187 | + gammalib.GEnergy(emax, "TeV")) | ||
| 188 | + | ||
| 189 | + # Create energy axis | ||
| 190 | + energy = [] | ||
| 191 | + for i in range(ebds.size()): | ||
| 192 | + energy.append(ebds.elogmean(i).TeV()) | ||
| 193 | + | ||
| 194 | + # Fill histogram | ||
| 195 | + counts = [0.0 for i in range(ebds.size())] | ||
| 196 | + for event in events: | ||
| 197 | + index = ebds.index(event.energy()) | ||
| 198 | + counts[index] = counts[index] + 1.0 | ||
| 199 | + | ||
| 200 | + # Create error bars | ||
| 201 | + error = [math.sqrt(c) for c in counts] | ||
| 202 | + | ||
| 203 | + # Get model values | ||
| 204 | + sum = 0.0 | ||
| 205 | + models = gammalib.GModels(xmlname) | ||
| 206 | + m = models[0] | ||
| 207 | + model = [] | ||
| 208 | + t = gammalib.GTime() | ||
| 209 | + for i in range(ebds.size()): | ||
| 210 | + eval = ebds.elogmean(i) | ||
| 211 | + ewidth = ebds.emax(i) - ebds.emin(i) | ||
| 212 | + f = m.npred(eval, t, obs) * ewidth.MeV() * duration | ||
| 213 | + sum += f | ||
| 214 | + model.append(f) | ||
| 215 | + print(str(sum) + " events expected from spectrum (integration).") | ||
| 216 | + | ||
| 217 | + # Plot data | ||
| 218 | + plt.loglog(energy, counts, 'ro') | ||
| 219 | + plt.errorbar(energy, counts, error, fmt=None, ecolor='r') | ||
| 220 | + | ||
| 221 | + # Plot model | ||
| 222 | + plt.plot(energy, model, 'b-') | ||
| 223 | + | ||
| 224 | + # Set axes | ||
| 225 | + plt.xlabel("Energy (TeV)") | ||
| 226 | + plt.ylabel("Number of events") | ||
| 227 | + | ||
| 228 | + # Notify | ||
| 229 | + print("PLEASE CLOSE WINDOW TO CONTINUE ...") | ||
| 230 | + | ||
| 231 | + # Show plot | ||
| 232 | + plt.show() | ||
| 233 | + | ||
| 234 | + # Return | ||
| 235 | + return | ||
| 236 | + | ||
| 237 | + | ||
| 238 | +#==========================# | ||
| 239 | +# Main routine entry point # | ||
| 240 | +#==========================# | ||
| 241 | +if __name__ == '__main__': | ||
| 242 | + """ | ||
| 243 | + Simulate events. | ||
| 244 | + """ | ||
| 245 | + # Dump header | ||
| 246 | + print("") | ||
| 247 | + print("*******************") | ||
| 248 | + print("* Simulate events *") | ||
| 249 | + print("*******************") | ||
| 250 | + | ||
| 251 | + # Set XML names | ||
| 252 | + xmlname = "model_bgd.xml" | ||
| 253 | + | ||
| 254 | + # Set simulation parameters | ||
| 255 | + duration = 360000.0 # Observation duration (s) | ||
| 256 | + emin = 0.1 # 0.1 TeV | ||
| 257 | + emax = 100.0 # 100 TeV | ||
| 258 | + ebins = 30 | ||
| 259 | + | ||
| 260 | + # Set observation | ||
| 261 | + obs = createobs(emin=emin, emax=emax, duration=duration) | ||
| 262 | + | ||
| 263 | + # Perform simulation | ||
| 264 | + #events = simulate(obs, xmlname) | ||
| 265 | + events = simulate_ctobssim(obs, xmlname) | ||
| 266 | + | ||
| 267 | + # Show events | ||
| 268 | + if has_matplotlib: | ||
| 269 | + show_events(events, xmlname, duration, emin, emax, ebins=ebins) |