add example sim

examples/sim.py

+import numpy as np
+from airshower import shower, utils, plotting
+import argparse
+
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--mass", default=1, type=int, help='mass number')
+parser.add_argument("--nfiles", default=1, type=int, help='mass number')
+parser.add_argument("--nevents", default=1000, type=int, help='mass number')
+args = parser.parse_args()
+
+print 'Simulating'
+print 'A', args.mass
+print 'nfiles', args.nfiles
+print 'nevents', args.nevents
+
+v_stations = utils.station_coordinates(9, layout='offset')
+
+for i in range(args.nfiles):
+    logE = 18.5 + 1.5 * np.random.rand(args.nevents)
+    mass = args.mass * np.ones(args.nevents)
+    data = shower.rand_events(logE, mass, v_stations)
+
+    np.savez_compressed(
+        'showers-A%i-%i.npz' % (args.mass, i),
+        detector=data['detector'],
+        logE=data['logE'],
+        mass=data['mass'],
+        Xmax=data['Xmax'],
+        showercore=data['showercore'],
+        showeraxis=data['showeraxis'],
+        showermax=data['showermax'],
+        time=data['time'],
+        signal=data['signal'])