Exemplo n.º 1
0
def test_impulse_deltav_general():
    from galpy.df import impulse_deltav_plummer, impulse_deltav_general
    from galpy.potential import PlummerPotential
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[3.4,0.,0.]]),
                                 numpy.array([4.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    pp= PlummerPotential(amp=1.5,b=4.)
    general_kick=\
        impulse_deltav_general(numpy.array([[3.4,0.,0.]]),
                               numpy.array([4.]),
                               3.,
                               numpy.array([0.,numpy.pi/2.,0.]),
                               pp)
    assert numpy.all(numpy.fabs(kick-general_kick) < 10.**tol), 'general kick calculation does not agree with Plummer calculation for a Plummer potential'
    # Same for a bunch of positions
    v= numpy.zeros((100,3))
    v[:,0]= 3.4
    xpos= numpy.random.normal(size=100)
    kick= impulse_deltav_plummer(v,
                                 xpos,
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 numpy.pi,numpy.exp(1.))
    pp= PlummerPotential(amp=numpy.pi,b=numpy.exp(1.))
    general_kick=\
        impulse_deltav_general(v,
                               xpos,
                               3.,
                               numpy.array([0.,numpy.pi/2.,0.]),
                               pp)
    assert numpy.all(numpy.fabs(kick-general_kick) < 10.**tol), 'general kick calculation does not agree with Plummer calculation for a Plummer potential'
    return None
Exemplo n.º 2
0
def test_impulse_deltav_general():
    from galpy.df import impulse_deltav_plummer, impulse_deltav_general
    from galpy.potential import PlummerPotential
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[3.4,0.,0.]]),
                                 numpy.array([4.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    pp= PlummerPotential(amp=1.5,b=4.)
    general_kick=\
        impulse_deltav_general(numpy.array([[3.4,0.,0.]]),
                               numpy.array([4.]),
                               3.,
                               numpy.array([0.,numpy.pi/2.,0.]),
                               pp)
    assert numpy.all(numpy.fabs(kick-general_kick) < 10.**tol), 'general kick calculation does not agree with Plummer calculation for a Plummer potential'
    # Same for a bunch of positions
    v= numpy.zeros((100,3))
    v[:,0]= 3.4
    xpos= numpy.random.normal(size=100)
    kick= impulse_deltav_plummer(v,
                                 xpos,
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 numpy.pi,numpy.exp(1.))
    pp= PlummerPotential(amp=numpy.pi,b=numpy.exp(1.))
    general_kick=\
        impulse_deltav_general(v,
                               xpos,
                               3.,
                               numpy.array([0.,numpy.pi/2.,0.]),
                               pp)
    assert numpy.all(numpy.fabs(kick-general_kick) < 10.**tol), 'general kick calculation does not agree with Plummer calculation for a Plummer potential'
    return None
Exemplo n.º 3
0
def test_impulse_deltav_plummerstream():
    from galpy.df import impulse_deltav_plummer, impulse_deltav_plummerstream
    from galpy.util import conversion
    V0, R0= 220., 8.
    GM= 10.**-2./conversion.mass_in_1010msol(V0,R0)
    rs= 0.625/R0
    b= rs
    stream_phi= numpy.linspace(-numpy.pi/2.,numpy.pi/2.,201)
    stream_r= 10./R0
    stream_v= 220./V0
    x_gc= stream_r*stream_phi
    v_gc= numpy.tile([0.000001,stream_v,0.000001],(201,1))
    w= numpy.array([0.,132.,176])/V0
    wmag= numpy.sqrt(numpy.sum(w**2.))
    tol= -5.
    # Plummer sphere kick
    kick= impulse_deltav_plummer(v_gc[101],x_gc[101],-b,w,GM,rs)
    # Kick from stream with length 0.01 r_s (should be ~Plummer sphere)
    dt= 0.01*rs*R0/wmag/V0*conversion.freq_in_kmskpc(V0,R0)
    stream_kick= impulse_deltav_plummerstream(\
        v_gc[101],x_gc[101],-b,w,lambda t: GM/dt,rs,-dt/2.,dt/2.)
    assert numpy.all(numpy.fabs((kick-stream_kick)/kick) < 10.**tol), 'Short stream impulse kick calculation does not agree with Plummer calculation by %g' % (numpy.amax(numpy.fabs((kick-stream_kick)/kick)))
    # Same for a bunch of positions
    kick= impulse_deltav_plummer(v_gc,x_gc,-b,w,GM,rs)
    # Kick from stream with length 0.01 r_s (should be ~Plummer sphere)
    dt= 0.01*rs*R0/wmag/V0*conversion.freq_in_kmskpc(V0,R0)
    stream_kick=\
        impulse_deltav_plummerstream(\
        v_gc,x_gc,-b,w,lambda t: GM/dt,rs,-dt/2.,dt/2.)
    assert numpy.all((numpy.fabs((kick-stream_kick)/kick) < 10.**tol)*(numpy.fabs(kick) >= 10**-4.)\
                         +(numpy.fabs((kick-stream_kick)) < 10**tol)*(numpy.fabs(kick) < 10**-4.)), 'Short stream impulse kick calculation does not agree with Plummer calculation by rel: %g, abs: %g' % (numpy.amax(numpy.fabs((kick-stream_kick)/kick)[numpy.fabs(kick) >= 10**-4.]),numpy.amax(numpy.fabs((kick-stream_kick))[numpy.fabs(kick) < 10**-3.]))
Exemplo n.º 4
0
def test_impulse_deltav_plummer_subhalo_perpendicular():
    from galpy.df import impulse_deltav_plummer
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[0.,numpy.pi,0.]]),
                                 numpy.array([0.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    # Should be B&T (8.152)
    assert numpy.fabs(kick[0,0]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    assert numpy.fabs(kick[0,2]+2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    # Same for along z
    kick= impulse_deltav_plummer(numpy.array([[0.,0.,numpy.pi]]),
                                 numpy.array([0.]),
                                 3.,
                                 numpy.array([0.,0.,numpy.pi/2.]),
                                 1.5,4.)
    # Should be B&T (8.152)
    assert numpy.fabs(kick[0,0]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    assert numpy.fabs(kick[0,1]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    return None
Exemplo n.º 5
0
def test_impulse_deltav_plummer_subhalo_perpendicular():
    from galpy.df import impulse_deltav_plummer
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[0.,numpy.pi,0.]]),
                                 numpy.array([0.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    # Should be B&T (8.152)
    assert numpy.fabs(kick[0,0]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    assert numpy.fabs(kick[0,2]+2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    # Same for along z
    kick= impulse_deltav_plummer(numpy.array([[0.,0.,numpy.pi]]),
                                 numpy.array([0.]),
                                 3.,
                                 numpy.array([0.,0.,numpy.pi/2.]),
                                 1.5,4.)
    # Should be B&T (8.152)
    assert numpy.fabs(kick[0,0]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    assert numpy.fabs(kick[0,1]-2.*1.5*3./numpy.pi*2./25.) < 10.**tol, 'Perpendicular kick of subhalo perpendicular not as expected'
    return None
Exemplo n.º 6
0
def test_impulse_deltav_plummer_curved_subhalo_perpendicular():
    from galpy.df import impulse_deltav_plummer, \
        impulse_deltav_plummer_curvedstream
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[3.4,0.,0.]]),
                                 numpy.array([4.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    curved_kick= impulse_deltav_plummer_curvedstream(\
        numpy.array([[3.4,0.,0.]]),
        numpy.array([[4.,0.,0.]]),
        3.,
        numpy.array([0.,numpy.pi/2.,0.]),
        numpy.array([0.,0.,0.]),
        numpy.array([3.4,0.,0.]),
        1.5,4.)
    # Should be equal
    assert numpy.all(numpy.fabs(kick-curved_kick) < 10.**tol), 'curved Plummer kick does not agree with straight kick for straight track'
    # Same for a bunch of positions
    v= numpy.zeros((100,3))
    v[:,0]= 3.4
    xpos= numpy.random.normal(size=100)
    kick= impulse_deltav_plummer(v,
                                 xpos,
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    xpos= numpy.array([xpos,numpy.zeros(100),numpy.zeros(100)]).T
    curved_kick= impulse_deltav_plummer_curvedstream(\
        v,
        xpos,
        3.,
        numpy.array([0.,numpy.pi/2.,0.]),
        numpy.array([0.,0.,0.]),
        numpy.array([3.4,0.,0.]),
        1.5,4.)
    # Should be equal
    assert numpy.all(numpy.fabs(kick-curved_kick) < 10.**tol), 'curved Plummer kick does not agree with straight kick for straight track'
    return None
Exemplo n.º 7
0
def test_impulse_deltav_plummer_curved_subhalo_perpendicular():
    from galpy.df import impulse_deltav_plummer, \
        impulse_deltav_plummer_curvedstream
    tol= -10.
    kick= impulse_deltav_plummer(numpy.array([[3.4,0.,0.]]),
                                 numpy.array([4.]),
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    curved_kick= impulse_deltav_plummer_curvedstream(\
        numpy.array([[3.4,0.,0.]]),
        numpy.array([[4.,0.,0.]]),
        3.,
        numpy.array([0.,numpy.pi/2.,0.]),
        numpy.array([0.,0.,0.]),
        numpy.array([3.4,0.,0.]),
        1.5,4.)
    # Should be equal
    assert numpy.all(numpy.fabs(kick-curved_kick) < 10.**tol), 'curved Plummer kick does not agree with straight kick for straight track'
    # Same for a bunch of positions
    v= numpy.zeros((100,3))
    v[:,0]= 3.4
    xpos= numpy.random.normal(size=100)
    kick= impulse_deltav_plummer(v,
                                 xpos,
                                 3.,
                                 numpy.array([0.,numpy.pi/2.,0.]),
                                 1.5,4.)
    xpos= numpy.array([xpos,numpy.zeros(100),numpy.zeros(100)]).T
    curved_kick= impulse_deltav_plummer_curvedstream(\
        v,
        xpos,
        3.,
        numpy.array([0.,numpy.pi/2.,0.]),
        numpy.array([0.,0.,0.]),
        numpy.array([3.4,0.,0.]),
        1.5,4.)
    # Should be equal
    assert numpy.all(numpy.fabs(kick-curved_kick) < 10.**tol), 'curved Plummer kick does not agree with straight kick for straight track'
    return None
Exemplo n.º 8
0
def test_impulse_deltav_plummerstream_tmaxerror():
    from galpy.df import impulse_deltav_plummer, impulse_deltav_plummerstream
    from galpy.util import conversion
    V0, R0= 220., 8.
    GM= 10.**-2./conversion.mass_in_1010msol(V0,R0)
    rs= 0.625/R0
    b= rs
    stream_phi= numpy.linspace(-numpy.pi/2.,numpy.pi/2.,201)
    stream_r= 10./R0
    stream_v= 220./V0
    x_gc= stream_r*stream_phi
    v_gc= numpy.tile([0.000001,stream_v,0.000001],(201,1))
    w= numpy.array([0.,132.,176])/V0
    wmag= numpy.sqrt(numpy.sum(w**2.))
    tol= -5.
    # Same for infinite integration limits
    kick= impulse_deltav_plummer(v_gc[101],x_gc[101],-b,w,GM,rs)
    # Kick from stream with length 0.01 r_s (should be ~Plummer sphere)
    dt= 0.01*rs*R0/wmag/V0*conversion.freq_in_kmskpc(V0,R0)
    with pytest.raises(ValueError) as excinfo:
        stream_kick= impulse_deltav_plummerstream(\
            v_gc[101],x_gc[101],-b,w,lambda t: GM/dt,rs)
    return None