def test_radius_from_time(self):
self.skip_no_scipy()
func = stellar_wind.RSquaredAcceleration()
star = Particle()
star.radius = 312. | units.RSun
star.acc_cutoff = 312*5. | units.RSun
star.initial_wind_velocity = 2 | units.kms
star.terminal_wind_velocity = 20 | units.kms
times = [0., 25., 100.] | units.yr
print "times", times
radii = func.radius_from_time(times, star)
print "radii", radii
self.assertAlmostEquals(radii[0], 312. | units.RSun)
self.assertAlmostEquals(radii[1], 22644.6086263 | units.RSun)
self.assertAlmostEquals(radii[2], 90704.1183516 | units.RSun)
return
times = numpy.linspace(0., 1, 100) | units.yr
radii = func.radius_from_time(times, star)
print radii
from matplotlib import pyplot
from amuse import plot as aplot
aplot.plot(times, radii/star.radius)
pyplot.show()
def create_star(self):
star = Particle()
star.radius = 2 | units.RSun
star.acc_cutoff = 10 | units.RSun
star.initial_wind_velocity = 4 | units.kms
star.terminal_wind_velocity = 12 | units.kms
return star
def test_radius_from_time(self):
self.skip_no_scipy()
func = stellar_wind.RSquaredAcceleration()
star = Particle()
star.radius = 312. | units.RSun
star.acc_cutoff = 312 * 5. | units.RSun
star.initial_wind_velocity = 2 | units.kms
star.terminal_wind_velocity = 20 | units.kms
times = [0., 25., 100.] | units.yr
print "times", times
radii = func.radius_from_time(times, star)
print "radii", radii
self.assertAlmostEquals(radii[0], 312. | units.RSun)
self.assertAlmostEquals(radii[1], 22644.6086263 | units.RSun)
self.assertAlmostEquals(radii[2], 90704.1183516 | units.RSun)
return
times = numpy.linspace(0., 1, 100) | units.yr
radii = func.radius_from_time(times, star)
print radii
from matplotlib import pyplot
from amuse import plot as aplot
aplot.plot(times, radii / star.radius)
pyplot.show()
def create_star(self):
star = Particle()
star.radius = 2 | units.RSun
star.acc_cutoff = 10 | units.RSun
star.initial_wind_velocity = 4 | units.kms
star.terminal_wind_velocity = 12 | units.kms
return star
def test_alternate_radius_function(self):
numpy.random.seed(123)
gen = stellar_wind.PositionGenerator()
# func = stellar_wind.LogisticVelocityAcceleration().radius_from_number
func = stellar_wind.ConstantVelocityAcceleration().radius_from_number
N = 100000
rmin = 2 | units.RSun
rmax = 6 | units.RSun
star = Particle()
star.radius = rmin
star.acc_cutoff = 10 | units.RSun
star.initial_wind_velocity = 4 | units.kms
star.terminal_wind_velocity = 12 | units.kms
p, _ = gen.generate_positions(N, rmin, rmax, func, star)
r = p.lengths()
self.assertEquals(len(r), N)
self.assertGreaterEqual(r.min(), rmin)
self.assertLessEqual(r.max(), rmax)
print r.mean()
self.assertAlmostEquals(r.mean(), 4.00196447056 | units.RSun)
return
r = r.value_in(units.RSun)
n_bins = 50
n, bins = numpy.histogram(r, n_bins)
bin_volume = 4./3. * numpy.pi * (bins[1:]**3 - bins[:-1]**3)
dens = n / bin_volume
bin_means = (bins[1:] + bins[:-1])/2.
from matplotlib import pyplot
pyplot.plot(bin_means, dens, '*')
pyplot.savefig("dens.pdf")
def test_alternate_radius_function(self):
numpy.random.seed(123)
gen = stellar_wind.PositionGenerator()
# func = stellar_wind.LogisticVelocityAcceleration().radius_from_number
func = stellar_wind.ConstantVelocityAcceleration().radius_from_number
N = 100000
rmin = 2 | units.RSun
rmax = 6 | units.RSun
star = Particle()
star.radius = rmin
star.acc_cutoff = 10 | units.RSun
star.initial_wind_velocity = 4 | units.kms
star.terminal_wind_velocity = 12 | units.kms
p, _ = gen.generate_positions(N, rmin, rmax, func, star)
r = p.lengths()
self.assertEquals(len(r), N)
self.assertGreaterEqual(r.min(), rmin)
self.assertLessEqual(r.max(), rmax)
print r.mean()
self.assertAlmostEquals(r.mean(), 4.00196447056 | units.RSun)
return
r = r.value_in(units.RSun)
n_bins = 50
n, bins = numpy.histogram(r, n_bins)
bin_volume = 4. / 3. * numpy.pi * (bins[1:]**3 - bins[:-1]**3)
dens = n / bin_volume
bin_means = (bins[1:] + bins[:-1]) / 2.
from matplotlib import pyplot
pyplot.plot(bin_means, dens, '*')
pyplot.savefig("dens.pdf")