def __init__(self,discpot,zlim,vlim,times=np.linspace(0,1,1001)*u.Gyr,zpt=31,vpt=31,zarray=False,varray=False):
"""
NAME:
__init__
PURPOSE:
Initialize a vertical disc in equilibrium
INPUT:
pot (galpy potential) - should be a 1-dimensional potential
zlim (float) - maximum height of the galactic disc in kpc
vlim (float) - maximum velocity of the galactic disc in km/s
OPTIONAL INPUTS:
times (array) - time array over which to integrate the disc orbits.
Otherwise, it defaults to 1001 timesteps over 5 Gyr.
zpt (int) - number of phase-space points along the z-axis
vpt (int) - number of phase-space points along the vz-axis
zarray (boolean) - if True, zlim is an array specifying the points along the z-axis at which to calculte the perturbation
varray (boolean) - if True, vlim is an array specifying the points along the vz-axis at which to calculte the perturbation
OUTPUT:
instance
"""
turn_physical_off(discpot) #1-dimensional potential object from Galpy
self.pot= discpot
self.InternalUnits= get_physical(self.pot)
if zarray:
self.zmax=np.max(np.abs(zlim))
self.znpt= len(zlim)
self.z= zlim
else:
self.zmax= zlim/self.InternalUnits['ro']
self.znpt= zpt
self.z= np.linspace(-self.zmax,self.zmax,self.znpt) # in galpy internal units
if varray:
self.vmax=np.max(np.abs(vlim))
self.vnpt= len(vlim)
self.v= vlim
else:
self.vmax= vlim/self.InternalUnits['vo']
self.vnpt= vpt
self.v= np.linspace(-self.vmax,self.vmax,self.vnpt) # in galpy internal units
self.tt= times
self.Jz,self.Oz= self.calc_JO()
self.integOrbits(self.tt)
def _coordinate_system(zmin_max, vmin_max, N, galactic_potential):
"""
:param zmin_max:
:param vmin_max:
:param N:
:param galactic_potential:
:return:
"""
_z = np.linspace(-zmin_max, zmin_max, N)
_v = np.linspace(-vmin_max, vmin_max, N)
turn_physical_off(galactic_potential)
units = get_physical(galactic_potential)
z_units_internal = _z / units['ro']
v_units_internal = _v / units['vo']
return z_units_internal, v_units_internal, galactic_potential, units
def test_get_physical():
#Test that the get_physical function returns the right scaling parameters
from galpy.util.bovy_conversion import get_physical
# Potential and variations thereof
from galpy.potential import MWPotential2014, DehnenBarPotential
dp = DehnenBarPotential
assert numpy.fabs(
get_physical(MWPotential2014[0]).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014[0]).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
ro, vo = 9., 230.
dp = DehnenBarPotential(ro=ro, vo=vo)
assert numpy.fabs(
get_physical(dp).get('ro') - ro
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(dp).get('vo') - vo
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014 + dp).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014 + dp).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014 + dp).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
assert numpy.fabs(
get_physical(MWPotential2014 + dp).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a Potential'
# Orbits
from galpy.orbit import Orbit
ro, vo = 10., 210.
o = Orbit(ro=ro, vo=vo)
assert numpy.fabs(
get_physical(o).get('ro') - ro
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an Orbit'
assert numpy.fabs(
get_physical(o).get('vo') - vo
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an Orbit'
# even though one shouldn't do this, let's test a list
assert numpy.fabs(
get_physical([o, o]).get('ro') - ro
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an Orbit'
assert numpy.fabs(
get_physical([o, o]).get('vo') - vo
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an Orbit'
# actionAngle
from galpy.actionAngle import actionAngleStaeckel
aAS = actionAngleStaeckel(pot=MWPotential2014, delta=0.45)
assert numpy.fabs(
get_physical(aAS).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an actionAngle instance'
assert numpy.fabs(
get_physical(aAS).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an actionAngle instance'
# This doesn't make much sense, but let's test...
ro, vo = 19., 130.
dp = DehnenBarPotential(ro=ro, vo=vo)
aAS = actionAngleStaeckel(pot=dp, delta=0.45, ro=ro, vo=vo)
assert numpy.fabs(
get_physical(aAS).get('ro') - ro
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an actionAngle instance'
assert numpy.fabs(
get_physical(aAS).get('vo') - vo
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for an actionAngle instance'
# DF
from galpy.df import quasiisothermaldf
aAS = actionAngleStaeckel(pot=MWPotential2014, delta=0.45)
qdf = quasiisothermaldf(1. / 3.,
0.2,
0.1,
1.,
1.,
aA=aAS,
pot=MWPotential2014)
assert numpy.fabs(
get_physical(qdf).get('ro') - 8.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a DF instance'
assert numpy.fabs(
get_physical(qdf).get('vo') - 220.
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a DF instance'
# non-standard ro,vo
from galpy.potential import MiyamotoNagaiPotential
ro, vo = 4., 330.
mp = MiyamotoNagaiPotential(a=0.5, b=0.1, ro=ro, vo=vo)
aAS = actionAngleStaeckel(pot=mp, delta=0.45, ro=ro, vo=vo)
qdf = quasiisothermaldf(1. / 3.,
0.2,
0.1,
1.,
1.,
aA=aAS,
pot=mp,
ro=ro,
vo=vo)
assert numpy.fabs(
get_physical(qdf).get('ro') - ro
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a DF instance'
assert numpy.fabs(
get_physical(qdf).get('vo') - vo
) < 1e-10, 'get_physical does not return the correct unit conversion parameter for a DF instance'
return None