def test_interpsnapshotKeplerPotential_eval_naz():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 1.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,51),
zgrid=(0.,0.2,51),
logR=False,
interpPot=True,
zsym=True,
numcores=1)
spaz= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,51),
zgrid=(0.,0.2,51),
logR=False,
interpPot=True,
zsym=True,
numcores=1,nazimuths=12)
#This just tests on the grid
rs= numpy.linspace(0.01,2.,21)
zs= numpy.linspace(-0.2,0.2,41)
for r in rs:
for z in zs:
assert numpy.fabs((sp(r,z)-spaz(r,z))/sp(r,z)) < 10.**-10., 'RZPot interpolation w/ InterpSnapShotPotential of KeplerPotential with different nazimuths fails at (R,z) = (%g,%g)' % (r,z)
#This tests within the grid, with vector evaluation
rs= numpy.linspace(0.01,2.,10)
zs= numpy.linspace(-0.2,0.2,20)
mr,mz= numpy.meshgrid(rs,zs)
mr= mr.flatten()
mz= mz.flatten()
assert numpy.all(numpy.fabs((sp(mr,mz)-spaz(mr,mz))/sp(mr,mz)) < 10.**-5.), 'RZPot interpolation w/ interpRZPotential with different nazimimuths fails for vector input'
return None
def test_interpsnapshotKeplerpotential_Rzderiv():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 2.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,101),
zgrid=(0.,0.2,101),
logR=False,
interpPot=True,
interpepifreq=True,
interpverticalfreq=True,
zsym=True)
kp= potential.KeplerPotential(amp=2.) #should be the same
#This just tests on the grid
rs= numpy.linspace(0.01,2.,21)[1:]
zs= numpy.linspace(-0.2,0.2,41)
zs= zs[zs != 0.]# avoid zero
# Test, but give small |z| a less constraining
for r in rs:
for z in zs:
assert numpy.fabs((sp.Rzderiv(r,z)-kp.Rzderiv(r,z))/kp.Rzderiv(r,z)) < 10.**-4.*(1.+19.*(numpy.fabs(z) < 0.05)), 'RZPot interpolation of Rzderiv w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g) by %g; value is %g' % (r,z,numpy.fabs((sp.Rzderiv(r,z)-kp.Rzderiv(r,z))/kp.Rzderiv(r,z)),kp.Rzderiv(r,z))
#This tests within the grid
rs= numpy.linspace(0.01,2.,10)[1:]
zs= numpy.linspace(-0.2,0.2,20)
for r in rs:
for z in zs:
assert numpy.fabs((sp.Rzderiv(r,z)-kp.Rzderiv(r,z))/kp.Rzderiv(r,z)) < 10.**-4.*(1.+19.*(numpy.fabs(z) < 0.05)), 'RZPot interpolation of Rzderiv w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g) by %g' % (r,z,numpy.fabs((sp.Rzderiv(r,z)-kp.Rzderiv(r,z))/kp.Rzderiv(r,z)))
return None
def test_interpsnapshotKeplerPotential_z2deriv():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 2.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,101),
zgrid=(0.,0.2,101),
logR=False,
interpPot=True,
interpverticalfreq=True,
zsym=True)
kp= potential.KeplerPotential(amp=2.) #should be the same
#This just tests on the grid
rs= numpy.linspace(0.01,2.,21)[1:]
zs= numpy.linspace(-0.2,0.2,41)
for r in rs:
for z in zs:
assert numpy.fabs((sp.z2deriv(r,z)-kp.z2deriv(r,z))/kp.z2deriv(r,z)) < 10.**-4., 'RZPot interpolation of z2deriv w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g) by %g' % (r,z,numpy.fabs((sp.z2deriv(r,z)-kp.z2deriv(r,z))/kp.z2deriv(r,z)))
#This tests within the grid
rs= numpy.linspace(0.01,2.,10)[1:]
zs= numpy.linspace(-0.2,0.2,20)
for r in rs:
for z in zs:
assert numpy.fabs((sp.z2deriv(r,z)-kp.z2deriv(r,z))/kp.z2deriv(r,z)) < 2.*10.**-4., 'RZPot interpolation of z2deriv w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g) by %g' % (r,z,numpy.fabs((sp.z2deriv(r,z)-kp.z2deriv(r,z))/kp.z2deriv(r,z)))
return None
def test_interpsnapshotKeplerPotential_normalize_units():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 4.
s['eps']= 0.
s['pos'].units= 'kpc'
s['vel'].units= 'km s**-1'
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,3.,201),
zgrid=(0.,0.2,201),
logR=False,
interpPot=True,
zsym=True)
#Currently unnormalized
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
# Normalize
sp.normalize(R0=1.)
assert numpy.fabs(sp.Rforce(1.,0.)+1.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
# De normalize
sp.denormalize()
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
# Also test when R0 =/= 1
sp.normalize(R0=2.)
assert numpy.fabs(sp.Rforce(1.,0.)+1.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
# De normalize
sp.denormalize()
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
return None
def test_interpsnapshotKeplerPotential_eval():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 1.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,201),
zgrid=(0.,0.2,201),
logR=False,
interpPot=True,
zsym=True,
numcores=1)
kp= potential.KeplerPotential(amp=1.) #should be the same
#This just tests on the grid
rs= numpy.linspace(0.01,2.,21)
zs= numpy.linspace(-0.2,0.2,41)
for r in rs:
for z in zs:
assert numpy.fabs((sp(r,z)-kp(r,z))/kp(r,z)) < 10.**-10., 'RZPot interpolation w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g)' % (r,z)
#This tests within the grid
rs= numpy.linspace(0.01,2.,10)
zs= numpy.linspace(-0.2,0.2,20)
for r in rs:
for z in zs:
assert numpy.fabs((sp(r,z)-kp(r,z))/kp(r,z)) < 10.**-5., 'RZPot interpolation w/ InterpSnapShotPotential of KeplerPotential fails at (R,z) = (%g,%g) by %g' % (r,z,numpy.fabs((sp(r,z)-kp(r,z))/kp(r,z)))
#Test all at the same time to use vector evaluation
mr,mz= numpy.meshgrid(rs,zs)
mr= mr.flatten()
mz= mz.flatten()
assert numpy.all(numpy.fabs((sp(mr,mz)-kp(mr,mz))/kp(mr,mz)) < 10.**-5.), 'RZPot interpolation w/ interpRZPotential fails for vector input'
return None
def test_interpsnapshotKeplerPotential_verticalfreq():
# Set up a snapshot with just one unit mass at the origin
s = pynbody.new(star=1)
s['mass'] = 2.
s['eps'] = 0.
sp = potential.InterpSnapshotRZPotential(s,
rgrid=(0.01, 2., 101),
zgrid=(0., 0.2, 101),
logR=False,
interpPot=True,
interpverticalfreq=True,
zsym=True)
kp = potential.KeplerPotential(normalize=2.) #should be the same
#This just tests on the grid
rs = numpy.linspace(0.01, 2., 21)[1:]
for r in rs:
assert numpy.fabs(
(sp.verticalfreq(r) - kp.verticalfreq(r)) / kp.verticalfreq(r)
) < 10.**-4., 'RZPot interpolation of verticalfreq w/ InterpSnapShotPotential of KeplerPotential fails at R = %g by %g' % (
r,
numpy.fabs((sp.verticalfreq(r) - kp.verticalfreq(r)) /
kp.verticalfreq(r)))
#This tests within the grid
rs = numpy.linspace(0.01, 2., 10)[1:]
for r in rs:
assert numpy.fabs(
(sp.verticalfreq(r) - kp.verticalfreq(r)) / kp.verticalfreq(r)
) < 10.**-4., 'RZPot interpolation of verticalfreq w/ InterpSnapShotPotential of KeplerPotential fails at R = %g by %g' % (
r,
numpy.fabs((sp.verticalfreq(r) - kp.verticalfreq(r)) /
kp.verticalfreq(r)))
return None
def test_interpsnapshotKeplerPotential_logR_eval():
# Set up a snapshot with just one unit mass at the origin
s = pynbody.new(star=1)
s['mass'] = 1.
s['eps'] = 0.
sp = potential.InterpSnapshotRZPotential(s,
rgrid=(numpy.log(0.01),
numpy.log(20.), 251),
logR=True,
zgrid=(0., 0.2, 201),
interpPot=True,
zsym=True)
kp = potential.KeplerPotential(amp=1.) #should be the same
rs = numpy.linspace(0.02, 16., 20)
zs = numpy.linspace(-0.15, 0.15, 40)
mr, mz = numpy.meshgrid(rs, zs)
mr = mr.flatten()
mz = mz.flatten()
assert numpy.all(
numpy.fabs((sp(mr, mz) - kp(mr, mz)) / kp(mr, mz)) < 10.**-5.
), 'RZPot interpolation w/ interpRZPotential fails for vector input, w/ logR at (R,z) = (%f,%f) by %g' % (
mr[numpy.argmax(numpy.fabs(
(sp(mr, mz) - kp(mr, mz)) / kp(mr, mz)))], mz[numpy.argmax(
numpy.fabs((sp(mr, mz) - kp(mr, mz)) / kp(mr, mz)))],
numpy.amax(numpy.fabs((sp(mr, mz) - kp(mr, mz)) / kp(mr, mz))))
return None
def test_interpsnapshotrzpotential_nopynbody():
# Test that if we cannot load pynbody, we get an ImportError
from galpy.potential_src import SnapshotRZPotential
SnapshotRZPotential._PYNBODY_LOADED= False
try:
sp= potential.InterpSnapshotRZPotential(1.) #1. doesn't matter
except ImportError: pass
else:
raise AssertionError("InterpSnapshotRZPotential w/o pynbody should have raised an error, but didn't")
return None
def test_interpsnapshotKeplerPotential_normalize():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 4.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,3.,201),
zgrid=(0.,0.2,201),
logR=False,
interpPot=True,
interpepifreq=True,
interpverticalfreq=True,
zsym=True)
nkp= potential.KeplerPotential(normalize=1.) # normalized Kepler
ukp= potential.KeplerPotential(amp=4.) # Un-normalized Kepler
#Currently unnormalized
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp(1.,0.1)-ukp(1.,0.1)) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.epifreq(1.)-ukp.epifreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.verticalfreq(1.)-ukp.verticalfreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
# Normalize
sp.normalize(R0=1.)
assert numpy.fabs(sp.Rforce(1.,0.)+1.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
assert numpy.fabs(sp(1.,0.1)-nkp(1.,0.1)) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.epifreq(1.)-nkp.epifreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.verticalfreq(1.)-nkp.verticalfreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
# De normalize
sp.denormalize()
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
assert numpy.fabs(sp(1.,0.1)-ukp(1.,0.1)) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.epifreq(1.)-ukp.epifreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.verticalfreq(1.)-ukp.verticalfreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
# Also test when R0 =/= 1
sp.normalize(R0=2.)
assert numpy.fabs(sp.Rforce(1.,0.)+1.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
assert numpy.fabs(sp(1.,0.1)-nkp(1.,0.1)) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.epifreq(1.)-nkp.epifreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.verticalfreq(1.)-nkp.verticalfreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
# De normalize
sp.denormalize()
assert numpy.fabs(sp.Rforce(1.,0.)+4.) < 10.**-7., "InterpSnapShotPotential that is assumed to be normalized doesn't behave as expected"
assert numpy.fabs(sp(1.,0.1)-ukp(1.,0.1)) < 10.**-7., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.epifreq(1.)-ukp.epifreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
assert numpy.fabs(sp.verticalfreq(1.)-ukp.verticalfreq(1.)) < 10.**-4., "InterpSnapShotPotential that is assumed to be unnormalized doesn't behave as expected"
return None
def test_interpsnapshotKeplerPotential_noc_eval():
# Set up a snapshot with just one unit mass at the origin
s= pynbody.new(star=1)
s['mass']= 1.
s['eps']= 0.
sp= potential.InterpSnapshotRZPotential(s,
rgrid=(0.01,2.,201),
zgrid=(0.,0.2,201),
logR=False,
interpPot=True,
zsym=True,
enable_c=False)
kp= potential.KeplerPotential(amp=1.) #should be the same
#Test all at the same time to use vector evaluation
rs= numpy.linspace(0.01,2.,10)
zs= numpy.linspace(-0.2,0.2,20)
mr,mz= numpy.meshgrid(rs,zs)
mr= mr.flatten()
mz= mz.flatten()
assert numpy.all(numpy.fabs((sp(mr,mz)-kp(mr,mz))/kp(mr,mz)) < 10.**-5.), 'RZPot interpolation w/ interpRZPotential fails for vector input, without enable_c'
return None
