def test_solve_fastpm_linear_growth():
pm = ParticleMesh(BoxSize=1024.0, Nmesh=(128, 128, 128), dtype='f8')
engine = FastPMEngine(pm)
code = CodeSegment(engine)
code.create_linear_field(whitenoise='whitenoise',
powerspectrum=pk,
dlinear_k='dlinear_k')
code.solve_fastpm(pt=pt,
dlinear_k='dlinear_k',
asteps=[0.1, 0.5, 1.0],
s='s',
v='v',
s1='s1',
s2='s2')
code.get_x(s='s', x='x')
code.paint_simple(x='x', density='density')
field = pm.generate_whitenoise(seed=1234, unitary=True).c2r()
density, dlinear_k, s = code.compute(['density', 'dlinear_k', 's'],
init={'whitenoise': field})
density_k = density.r2c()
p_lin = FFTPower(FieldMesh(dlinear_k), mode='1d')
p_nonlin = FFTPower(FieldMesh(density), mode='1d')
# the simulation shall do a linear growth
t1 = abs((p_nonlin.power['power'] / p_lin.power['power'])**0.5)
assert_allclose(t1[1:4], 1.0, rtol=5e-2)
def test_solve_lpt():
pm = ParticleMesh(BoxSize=8.0, Nmesh=(4, 4, 4), dtype='f8')
engine = FastPMEngine(pm)
code = CodeSegment(engine)
code.create_linear_field(whitenoise='whitenoise',
powerspectrum=pk,
dlinear_k='dlinear_k')
code.solve_lpt(pt=pt,
dlinear_k='dlinear_k',
aend=0.1,
s='s',
v='v',
s1='s1',
s2='s2')
field = pm.generate_whitenoise(seed=1234).c2r()
s1, s2 = code.compute(['s1', 's2'], init={'whitenoise': field})
dlin_k = code.compute('dlinear_k', init={'whitenoise': field})
s1, tape = code.compute('s1', init={'whitenoise': field}, return_tape=True)
# from fastpm.operators import lpt1, lpt2source
# s1_truth = lpt1(dlin_k, engine.q, resampler='cic')
# dlin2_k = lpt2source(dlin_k)
# s2_truth = lpt1(dlin2_k, engine.q, resampler='cic')
# assert_allclose(s1, s1_truth, rtol=1e-4)
# assert_allclose(s2, s2_truth, rtol=1e-4)
eps = field.cnorm()**0.5 * 1e-4
check_grad(code,
's1',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
's2',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
's',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
'v',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
def test_solve_fastpm():
pm = ParticleMesh(BoxSize=8.0, Nmesh=(4, 4, 4), dtype='f8')
engine = FastPMEngine(pm, shift=0.5, B=1)
code = CodeSegment(engine)
code.create_linear_field(whitenoise='whitenoise',
powerspectrum=pk,
dlinear_k='dlinear_k')
code.solve_fastpm(pt=pt,
dlinear_k='dlinear_k',
asteps=[0.1, 1.0],
s='s',
v='v',
s1='s1',
s2='s2')
# code.solve_fastpm(pt=pt, dlinear_k='dlinear_k', asteps=[1.0], s='s', v='v', s1='s1', s2='s2')
code.get_x(s='s', x='x')
code.paint_simple(x='x', density='density')
field = pm.generate_whitenoise(seed=1234, unitary=True).c2r()
eps = field.cnorm()**0.5 * 1e-5
check_grad(code,
's1',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
's',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
'v',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
check_grad(code,
'density',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
def test_project():
pm = ParticleMesh(BoxSize=8.0, Nmesh=(4, 4, 4), dtype='f8')
engine = FastPMEngine(pm, shift=0.5, B=1)
code = CodeSegment(engine)
code.project(field='whitenoise', projection='projection')
field = pm.generate_whitenoise(seed=1234, unitary=True).c2r()
eps = field.cnorm()**0.5 * 1e-5
check_grad(code,
'projection',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)
def test_features(comm):
pm = ParticleMesh(BoxSize=8.0, Nmesh=(4, 4, 4), dtype='f8', comm=comm)
engine = FastPMEngine(pm, shift=0.5, B=1)
code = CodeSegment(engine)
code.find_neighbours(field='whitenoise', features='features')
field = pm.generate_whitenoise(seed=1234, unitary=True).c2r()
field[...] = numpy.arange(field.csize).reshape(field.cshape)[field.slices]
eps = field.cnorm()**0.5 * 1e-5
features = code.compute('features', init={'whitenoise': field})
check_grad(code,
'features',
'whitenoise',
init={'whitenoise': field},
eps=eps,
rtol=1e-8)