def test_seed(self):
#unseeded
r0 = random.uniform(0, 1)
r1 = random.expovariate(3000)
r2 = random.gauss(1, 3)
#seed
random.seed(0xdeadbeef)
a0 = random.uniform(0, 1)
a1 = random.expovariate(3)
a2 = random.gauss(1, 3)
#reseed
random.seed(0xdeadbeef)
b0 = random.uniform(0, 1)
b1 = random.expovariate(3)
b2 = random.gauss(1, 3)
#unseeded should be different to seeded
self.assertFalse(a0 == r0)
self.assertFalse(a1 == r1)
self.assertFalse(a2 == r2)
#reseeded should be same as seeded
self.assertEqual(a0, b0)
self.assertEqual(a1, b1)
self.assertEqual(a2, b2)
def path_length(self, ptc):
'''path before decay within material, for a particle.
The particle must have a method is_em to indicate if the radiation
or interaction length should be used.
'''
freepath = self.x0 if ptc.is_em() else self.lambdaI
if freepath == 0.0:
return sys.float_info.max
else:
return random.expovariate(1./freepath)
'''Describe material used in a detector layer.'''
def __init__(self, name, x0, lambdaI):
'''Parameters:
- name: e.g. iron
- x0: radiation length
- lambdaI : interaction length
'''
self.name = name
self.x0 = x0
self.lambdaI = lambdaI
def path_length(self, ptc):
'''path before decay within material, for a particle.
The particle must have a method is_em to indicate if the radiation
or interaction length should be used.
'''
freepath = self.x0 if ptc.is_em() else self.lambdaI
if freepath == 0.0:
return sys.float_info.max
else:
return random.expovariate(1./freepath)
void = Material('void', 0, 0)
if __name__ == '__main__':
import matplotlib.pyplot as plt
a = [random.expovariate(25.) for i in range(10000)]
n, bins, patches = plt.hist(a, 50, normed=1, facecolor='green', alpha=0.75)
plt.show()
