def nbody_fn(mesh,
klin,
plin,
nc=FLAGS.nc,
bs=FLAGS.box_size,
batch_size=FLAGS.batch_size,
a0=FLAGS.a0,
a=FLAGS.af,
nsteps=FLAGS.nsteps,
dtype=tf.float32):
""" Pyramid N-body function
"""
stages = np.linspace(a0, a, nsteps, endpoint=True)
# Define the named dimensions
# Parameters of the small scales decomposition
n_block_x = FLAGS.nx
n_block_y = FLAGS.ny
n_block_z = 1
halo_size = FLAGS.hsize
# Parameters of the large scales decomposition
downsampling_factor = FLAGS.dsample
lnc = nc // 2**downsampling_factor
fx_dim = mtf.Dimension("nx", nc)
fy_dim = mtf.Dimension("ny", nc)
fz_dim = mtf.Dimension("nz", nc)
tfx_dim = mtf.Dimension("tx", nc)
tfy_dim = mtf.Dimension("ty", nc)
tfz_dim = mtf.Dimension("tz", nc)
# Dimensions of the low resolution grid
x_dim = mtf.Dimension("nx_lr", lnc)
y_dim = mtf.Dimension("ny_lr", lnc)
z_dim = mtf.Dimension("nz_lr", lnc)
tx_dim = mtf.Dimension("tx_lr", lnc)
ty_dim = mtf.Dimension("ty_lr", lnc)
tz_dim = mtf.Dimension("tz_lr", lnc)
nx_dim = mtf.Dimension('nx_block', n_block_x)
ny_dim = mtf.Dimension('ny_block', n_block_y)
nz_dim = mtf.Dimension('nz_block', n_block_z)
sx_dim = mtf.Dimension('sx_block', nc // n_block_x)
sy_dim = mtf.Dimension('sy_block', nc // n_block_y)
sz_dim = mtf.Dimension('sz_block', nc // n_block_z)
batch_dim = mtf.Dimension("batch", batch_size)
pk_dim = mtf.Dimension("npk", len(plin))
pk = mtf.import_tf_tensor(mesh, plin.astype('float32'), shape=[pk_dim])
# Compute necessary Fourier kernels
kvec = flowpm.kernels.fftk((nc, nc, nc), symmetric=False)
kx = mtf.import_tf_tensor(
mesh, kvec[0].squeeze().astype('float32'), shape=[tfx_dim])
ky = mtf.import_tf_tensor(
mesh, kvec[1].squeeze().astype('float32'), shape=[tfy_dim])
kz = mtf.import_tf_tensor(
mesh, kvec[2].squeeze().astype('float32'), shape=[tfz_dim])
kv = [ky, kz, kx]
# kvec for low resolution grid
kvec_lr = flowpm.kernels.fftk([lnc, lnc, lnc], symmetric=False)
kx_lr = mtf.import_tf_tensor(
mesh,
kvec_lr[0].squeeze().astype('float32') / 2**downsampling_factor,
shape=[tx_dim])
ky_lr = mtf.import_tf_tensor(
mesh,
kvec_lr[1].squeeze().astype('float32') / 2**downsampling_factor,
shape=[ty_dim])
kz_lr = mtf.import_tf_tensor(
mesh,
kvec_lr[2].squeeze().astype('float32') / 2**downsampling_factor,
shape=[tz_dim])
kv_lr = [ky_lr, kz_lr, kx_lr]
# kvec for high resolution blocks
padded_sx_dim = mtf.Dimension('padded_sx_block',
nc // n_block_x + 2 * halo_size)
padded_sy_dim = mtf.Dimension('padded_sy_block',
nc // n_block_y + 2 * halo_size)
padded_sz_dim = mtf.Dimension('padded_sz_block',
nc // n_block_z + 2 * halo_size)
kvec_hr = flowpm.kernels.fftk([
nc // n_block_x + 2 * halo_size, nc // n_block_y + 2 * halo_size,
nc // n_block_z + 2 * halo_size
],
symmetric=False)
kx_hr = mtf.import_tf_tensor(
mesh, kvec_hr[0].squeeze().astype('float32'), shape=[padded_sx_dim])
ky_hr = mtf.import_tf_tensor(
mesh, kvec_hr[1].squeeze().astype('float32'), shape=[padded_sy_dim])
kz_hr = mtf.import_tf_tensor(
mesh, kvec_hr[2].squeeze().astype('float32'), shape=[padded_sz_dim])
kv_hr = [ky_hr, kz_hr, kx_hr]
shape = [batch_dim, fx_dim, fy_dim, fz_dim]
lr_shape = [batch_dim, x_dim, y_dim, z_dim]
hr_shape = [batch_dim, nx_dim, ny_dim, nz_dim, sx_dim, sy_dim, sz_dim]
part_shape = [batch_dim, fx_dim, fy_dim, fz_dim]
# Compute initial initial conditions distributed
initc = mtfpm.linear_field(mesh, shape, bs, nc, pk, kv)
# Reshaping array into high resolution mesh
field = mtf.slicewise(
lambda x: tf.expand_dims(
tf.expand_dims(tf.expand_dims(x, axis=1), axis=1), axis=1), [initc],
output_dtype=tf.float32,
output_shape=hr_shape,
name='my_reshape',
splittable_dims=lr_shape[:-1] + hr_shape[1:4] + part_shape[1:3])
for block_size_dim in hr_shape[-3:]:
field = mtf.pad(field, [halo_size, halo_size], block_size_dim.name)
for blocks_dim, block_size_dim in zip(hr_shape[1:4], field.shape[-3:]):
field = mpm.halo_reduce(field, blocks_dim, block_size_dim, halo_size)
field = mtf.reshape(field, field.shape + [mtf.Dimension('h_dim', 1)])
high = field
low = mesh_utils.downsample(field, downsampling_factor, antialias=True)
low = mtf.reshape(low, low.shape[:-1])
high = mtf.reshape(high, high.shape[:-1])
for block_size_dim in hr_shape[-3:]:
low = mtf.slice(low, halo_size // 2**downsampling_factor,
block_size_dim.size // 2**downsampling_factor,
block_size_dim.name)
# Hack usisng custom reshape because mesh is pretty dumb
low = mtf.slicewise(
lambda x: x[:, 0, 0, 0], [low],
output_dtype=tf.float32,
output_shape=lr_shape,
name='my_dumb_reshape',
splittable_dims=lr_shape[:-1] + hr_shape[:4])
state = mtfpm.lpt_init(
low,
high,
0.1,
kv_lr,
kv_hr,
halo_size,
hr_shape,
lr_shape,
part_shape[1:],
downsampling_factor=downsampling_factor,
antialias=True,
)
final_state = mtfpm.nbody(
state,
stages,
lr_shape,
hr_shape,
kv_lr,
kv_hr,
halo_size,
downsampling_factor=downsampling_factor)
# paint the field
final_field = mtf.zeros(mesh, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
final_field = mtf.pad(final_field, [halo_size, halo_size],
block_size_dim.name)
final_field = mesh_utils.cic_paint(final_field, final_state[0], halo_size)
# Halo exchange
for blocks_dim, block_size_dim in zip(hr_shape[1:4], final_field.shape[-3:]):
final_field = mpm.halo_reduce(final_field, blocks_dim, block_size_dim,
halo_size)
# Remove borders
for block_size_dim in hr_shape[-3:]:
final_field = mtf.slice(final_field, halo_size, block_size_dim.size,
block_size_dim.name)
final_field = mtf.slicewise(
lambda x: x[:, 0, 0, 0], [final_field],
output_dtype=tf.float32,
output_shape=[batch_dim, fx_dim, fy_dim, fz_dim],
name='my_dumb_reshape',
splittable_dims=part_shape[:-1] + hr_shape[:4])
return initc, final_field
def recon_prototype(mesh,
data,
nc=FLAGS.nc,
bs=FLAGS.box_size,
batch_size=FLAGS.batch_size,
a0=FLAGS.a0,
a=FLAGS.af,
nsteps=FLAGS.nsteps,
dtype=tf.float32):
"""
Prototype of function computing LPT deplacement.
Returns output tensorflow and mesh tensorflow tensors
"""
if dtype == tf.float32:
npdtype = "float32"
cdtype = tf.complex64
elif dtype == tf.float64:
npdtype = "float64"
cdtype = tf.complex128
print(dtype, npdtype)
# Compute a few things first, using simple tensorflow
stages = np.linspace(a0, a, nsteps, endpoint=True)
#graph = mtf.Graph()
#mesh = mtf.Mesh(graph, "my_mesh")
# Define the named dimensions
# Parameters of the small scales decomposition
n_block_x = FLAGS.nx
n_block_y = FLAGS.ny
n_block_z = 1
halo_size = FLAGS.hsize
if halo_size >= 0.5 * min(nc // n_block_x, nc // n_block_y,
nc // n_block_z):
new_size = int(0.5 *
min(nc // n_block_x, nc // n_block_y, nc // n_block_z))
print('WARNING: REDUCING HALO SIZE from %d to %d' %
(halo_size, new_size))
halo_size = new_size
# Parameters of the large scales decomposition
downsampling_factor = 2
lnc = nc // 2**downsampling_factor
fx_dim = mtf.Dimension("nx", nc)
fy_dim = mtf.Dimension("ny", nc)
fz_dim = mtf.Dimension("nz", nc)
tfx_dim = mtf.Dimension("tx", nc)
tfy_dim = mtf.Dimension("ty", nc)
tfz_dim = mtf.Dimension("tz", nc)
# Dimensions of the low resolution grid
x_dim = mtf.Dimension("nx_lr", lnc)
y_dim = mtf.Dimension("ny_lr", lnc)
z_dim = mtf.Dimension("nz_lr", lnc)
tx_dim = mtf.Dimension("tx_lr", lnc)
ty_dim = mtf.Dimension("ty_lr", lnc)
tz_dim = mtf.Dimension("tz_lr", lnc)
nx_dim = mtf.Dimension('nx_block', n_block_x)
ny_dim = mtf.Dimension('ny_block', n_block_y)
nz_dim = mtf.Dimension('nz_block', n_block_z)
sx_dim = mtf.Dimension('sx_block', nc // n_block_x)
sy_dim = mtf.Dimension('sy_block', nc // n_block_y)
sz_dim = mtf.Dimension('sz_block', nc // n_block_z)
k_dims = [tx_dim, ty_dim, tz_dim]
batch_dim = mtf.Dimension("batch", batch_size)
klin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[0]
plin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[1]
ipklin = iuspline(klin, plin)
pk_dim = mtf.Dimension("npk", len(plin))
pk = mtf.import_tf_tensor(mesh, plin.astype(npdtype), shape=[pk_dim])
# Compute necessary Fourier kernels
kvec = flowpm.kernels.fftk((nc, nc, nc), symmetric=False, dtype=npdtype)
kx = mtf.import_tf_tensor(mesh,
kvec[0].squeeze().astype(npdtype),
shape=[tfx_dim])
ky = mtf.import_tf_tensor(mesh,
kvec[1].squeeze().astype(npdtype),
shape=[tfy_dim])
kz = mtf.import_tf_tensor(mesh,
kvec[2].squeeze().astype(npdtype),
shape=[tfz_dim])
kv = [ky, kz, kx]
# kvec for low resolution grid
kvec_lr = flowpm.kernels.fftk([lnc, lnc, lnc],
symmetric=False,
dtype=npdtype)
kx_lr = mtf.import_tf_tensor(mesh,
kvec_lr[0].squeeze().astype(npdtype) /
2**downsampling_factor,
shape=[tx_dim])
ky_lr = mtf.import_tf_tensor(mesh,
kvec_lr[1].squeeze().astype(npdtype) /
2**downsampling_factor,
shape=[ty_dim])
kz_lr = mtf.import_tf_tensor(mesh,
kvec_lr[2].squeeze().astype(npdtype) /
2**downsampling_factor,
shape=[tz_dim])
kv_lr = [ky_lr, kz_lr, kx_lr]
# kvec for high resolution blocks
padded_sx_dim = mtf.Dimension('padded_sx_block',
nc // n_block_x + 2 * halo_size)
padded_sy_dim = mtf.Dimension('padded_sy_block',
nc // n_block_y + 2 * halo_size)
padded_sz_dim = mtf.Dimension('padded_sz_block',
nc // n_block_z + 2 * halo_size)
kvec_hr = flowpm.kernels.fftk([
nc // n_block_x + 2 * halo_size, nc // n_block_y + 2 * halo_size,
nc // n_block_z + 2 * halo_size
],
symmetric=False,
dtype=npdtype)
kx_hr = mtf.import_tf_tensor(mesh,
kvec_hr[0].squeeze().astype(npdtype),
shape=[padded_sx_dim])
ky_hr = mtf.import_tf_tensor(mesh,
kvec_hr[1].squeeze().astype(npdtype),
shape=[padded_sy_dim])
kz_hr = mtf.import_tf_tensor(mesh,
kvec_hr[2].squeeze().astype(npdtype),
shape=[padded_sz_dim])
kv_hr = [ky_hr, kz_hr, kx_hr]
# kvec for prior blocks
prior_sx_dim = mtf.Dimension('prior_sx_block', nc // n_block_x)
prior_sy_dim = mtf.Dimension('prior_sy_block', nc // n_block_y)
prior_sz_dim = mtf.Dimension('prior_sz_block', nc // n_block_z)
kvec_pr = flowpm.kernels.fftk(
[nc // n_block_x, nc // n_block_y, nc // n_block_z],
symmetric=False,
dtype=npdtype)
kx_pr = mtf.import_tf_tensor(mesh,
kvec_pr[0].squeeze().astype(npdtype),
shape=[prior_sx_dim])
ky_pr = mtf.import_tf_tensor(mesh,
kvec_pr[1].squeeze().astype(npdtype),
shape=[prior_sy_dim])
kz_pr = mtf.import_tf_tensor(mesh,
kvec_pr[2].squeeze().astype(npdtype),
shape=[prior_sz_dim])
kv_pr = [ky_pr, kz_pr, kx_pr]
shape = [batch_dim, fx_dim, fy_dim, fz_dim]
lr_shape = [batch_dim, x_dim, y_dim, z_dim]
hr_shape = [batch_dim, nx_dim, ny_dim, nz_dim, sx_dim, sy_dim, sz_dim]
part_shape = [batch_dim, fx_dim, fy_dim, fz_dim]
## Compute initial initial conditions distributed
fieldvar = mtf.get_variable(mesh, 'linear', hr_shape)
input_field = tf.placeholder(data.dtype, [
batch_size, n_block_x, n_block_y, n_block_z, nc // n_block_x,
nc // n_block_y, nc // n_block_z
])
mtfinp = mtf.import_tf_tensor(mesh, input_field, shape=hr_shape)
linearop = mtf.assign(fieldvar, mtfinp)
#
field = fieldvar
initc = mtf.slicewise(lambda x: x[:, 0, 0, 0], [field],
output_dtype=tf.float32,
output_shape=[batch_dim, fx_dim, fy_dim, fz_dim],
name='my_dumb_reshape',
splittable_dims=part_shape[:-1] + hr_shape[:4])
#
for block_size_dim in hr_shape[-3:]:
field = mtf.pad(field, [halo_size, halo_size], block_size_dim.name)
for blocks_dim, block_size_dim in zip(hr_shape[1:4], field.shape[-3:]):
field = mpm.halo_reduce(field, blocks_dim, block_size_dim, halo_size)
field = mtf.reshape(field, field.shape + [mtf.Dimension('h_dim', 1)])
high = field
low = mesh_utils.downsample(field, downsampling_factor, antialias=True)
low = mtf.reshape(low, low.shape[:-1])
high = mtf.reshape(high, high.shape[:-1])
for block_size_dim in hr_shape[-3:]:
low = mtf.slice(low, halo_size // 2**downsampling_factor,
block_size_dim.size // 2**downsampling_factor,
block_size_dim.name)
# Hack usisng custom reshape because mesh is pretty dumb
low = mtf.slicewise(lambda x: x[:, 0, 0, 0], [low],
output_dtype=initc.dtype,
output_shape=lr_shape,
name='my_dumb_reshape',
splittable_dims=lr_shape[:-1] + hr_shape[:4])
# Here we can run our nbody
if FLAGS.nbody:
state = mtfpm.lpt_init(low,
high,
0.1,
kv_lr,
kv_hr,
halo_size,
hr_shape,
lr_shape,
part_shape[1:],
downsampling_factor=downsampling_factor,
antialias=True)
final_state = mtfpm.nbody(state,
stages,
lr_shape,
hr_shape,
kv_lr,
kv_hr,
halo_size,
downsampling_factor=downsampling_factor)
else:
final_state = mtfpm.lpt_init(low,
high,
stages[-1],
kv_lr,
kv_hr,
halo_size,
hr_shape,
lr_shape,
part_shape[1:],
downsampling_factor=downsampling_factor,
antialias=True)
# paint the field
final_field = mtf.zeros(mesh, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
final_field = mtf.pad(final_field, [halo_size, halo_size],
block_size_dim.name)
final_field = mesh_utils.cic_paint(final_field, final_state[0], halo_size)
# Halo exchange
for blocks_dim, block_size_dim in zip(hr_shape[1:4],
final_field.shape[-3:]):
final_field = mpm.halo_reduce(final_field, blocks_dim, block_size_dim,
halo_size)
# Remove borders
for block_size_dim in hr_shape[-3:]:
final_field = mtf.slice(final_field, halo_size, block_size_dim.size,
block_size_dim.name)
final_field = mtf.slicewise(
lambda x: x[:, 0, 0, 0], [final_field],
output_dtype=dtype,
output_shape=[batch_dim, fx_dim, fy_dim, fz_dim],
name='my_dumb_reshape',
splittable_dims=part_shape[:-1] + hr_shape[:4])
mtfdata = mtf.import_tf_tensor(mesh,
tf.convert_to_tensor(data),
shape=shape)
# Get prior
k_dims_pr = [d.shape[0] for d in kv_pr]
k_dims_pr = [k_dims_pr[2], k_dims_pr[0], k_dims_pr[1]]
cfield = mesh_utils.r2c3d(fieldvar, k_dims_pr, dtype=cdtype)
def _cwise_prior(kfield, pk, kx, ky, kz):
kx = tf.reshape(kx, [-1, 1, 1])
ky = tf.reshape(ky, [1, -1, 1])
kz = tf.reshape(kz, [1, 1, -1])
kk = tf.sqrt((kx / bs * nc)**2 + (ky / bs * nc)**2 + (kz / bs * nc)**2)
kshape = kk.shape
kk = tf.reshape(kk, [-1])
pkmesh = tfp.math.interp_regular_1d_grid(
x=kk,
x_ref_min=1e-05,
x_ref_max=1000.0,
y_ref=pk,
grid_regularizing_transform=tf.log)
priormesh = tf.reshape(pkmesh, kshape)
return tf.abs(kfield) / priormesh**0.5
cpfield = mtf.cwise(_cwise_prior, [cfield, pk] + kv_pr,
output_dtype=tf.float32)
prior = mtf.reduce_sum(mtf.square(cpfield)) * bs**3
# Total loss
diff = (final_field - mtfdata)
R0 = tf.placeholder(tf.float32, shape=())
def _cwise_smooth(kfield, kx, ky, kz):
kx = tf.reshape(kx, [-1, 1, 1])
ky = tf.reshape(ky, [1, -1, 1])
kz = tf.reshape(kz, [1, 1, -1])
kk = (kx / bs * nc)**2 + (ky / bs * nc)**2 + (kz / bs * nc)**2
wts = tf.cast(tf.exp(-kk * (R0 * bs / nc)**2), kfield.dtype)
return kfield * wts
cdiff = mesh_utils.r2c3d(diff, k_dims_pr, dtype=cdtype)
cdiff = mtf.cwise(_cwise_smooth, [cdiff] + kv_pr, output_dtype=cdtype)
diff = mesh_utils.c2r3d(cdiff, diff.shape[-3:], dtype=dtype)
chisq = mtf.reduce_sum(mtf.square(diff))
loss = chisq + prior
#return initc, final_field, loss, linearop, input_field
nyq = np.pi * nc / bs
def _cwise_highpass(kfield, kx, ky, kz):
kx = tf.reshape(kx, [-1, 1, 1])
ky = tf.reshape(ky, [1, -1, 1])
kz = tf.reshape(kz, [1, 1, -1])
kk = (kx / bs * nc)**2 + (ky / bs * nc)**2 + (kz / bs * nc)**2
wts = tf.cast(tf.exp(-kk * (R0 * bs / nc + 1 / nyq)**2), kfield.dtype)
return kfield * (1 - wts)
var_grads = mtf.gradients([loss], [fieldvar])
cgrads = mesh_utils.r2c3d(var_grads[0], k_dims_pr, dtype=cdtype)
cgrads = mtf.cwise(_cwise_highpass, [cgrads] + kv_pr, output_dtype=cdtype)
var_grads = [
mesh_utils.c2r3d(cgrads, var_grads[0].shape[-3:], dtype=dtype)
]
lr = tf.placeholder(tf.float32, shape=())
update_op = mtf.assign(fieldvar, fieldvar - var_grads[0] * lr)
return initc, final_field, loss, var_grads, update_op, linearop, input_field, lr, R0
def lpt_prototype(mesh,
initial_conditions,
derivs,
nc=FLAGS.nc,
bs=FLAGS.box_size,
batch_size=FLAGS.batch_size,
a0=FLAGS.a0,
a=FLAGS.af,
nsteps=FLAGS.nsteps):
"""
Prototype of function computing LPT deplacement.
Returns output tensorflow and mesh tensorflow tensors
"""
stages = np.linspace(a0, a, nsteps, endpoint=True)
lap, grad_x, grad_y, grad_z = derivs
klin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[0]
plin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[1]
ipklin = iuspline(klin, plin)
stages = np.linspace(a0, a, nsteps, endpoint=True)
# Define the named dimensions
# Parameters of the small scales decomposition
n_block_x = FLAGS.nx
n_block_y = FLAGS.ny
n_block_z = 1
halo_size = FLAGS.hsize
# Parameters of the large scales decomposition
downsampling_factor = FLAGS.dsample
lnc = nc // 2**downsampling_factor
#
fx_dim = mtf.Dimension("nx", nc)
fy_dim = mtf.Dimension("ny", nc)
fz_dim = mtf.Dimension("nz", nc)
# Dimensions of the low resolution grid
x_dim = mtf.Dimension("nx_lr", lnc)
y_dim = mtf.Dimension("ny_lr", lnc)
z_dim = mtf.Dimension("nz_lr", lnc)
tx_dim = mtf.Dimension("tx_lr", lnc)
ty_dim = mtf.Dimension("ty_lr", lnc)
tz_dim = mtf.Dimension("tz_lr", lnc)
nx_dim = mtf.Dimension('nx_block', n_block_x)
ny_dim = mtf.Dimension('ny_block', n_block_y)
nz_dim = mtf.Dimension('nz_block', n_block_z)
sx_dim = mtf.Dimension('sx_block', nc // n_block_x)
sy_dim = mtf.Dimension('sy_block', nc // n_block_y)
sz_dim = mtf.Dimension('sz_block', nc // n_block_z)
k_dims = [tx_dim, ty_dim, tz_dim]
batch_dim = mtf.Dimension("batch", batch_size)
pk_dim = mtf.Dimension("npk", len(plin))
pk = mtf.import_tf_tensor(mesh, plin.astype('float32'), shape=[pk_dim])
# kvec for low resolution grid
kvec_lr = flowpm.kernels.fftk([lnc, lnc, lnc], symmetric=False)
kx_lr = mtf.import_tf_tensor(mesh,
kvec_lr[0].squeeze().astype('float32') /
2**downsampling_factor,
shape=[tx_dim])
ky_lr = mtf.import_tf_tensor(mesh,
kvec_lr[1].squeeze().astype('float32') /
2**downsampling_factor,
shape=[ty_dim])
kz_lr = mtf.import_tf_tensor(mesh,
kvec_lr[2].squeeze().astype('float32') /
2**downsampling_factor,
shape=[tz_dim])
kv_lr = [ky_lr, kz_lr, kx_lr]
# kvec for high resolution blocks
padded_sx_dim = mtf.Dimension('padded_sx_block',
nc // n_block_x + 2 * halo_size)
padded_sy_dim = mtf.Dimension('padded_sy_block',
nc // n_block_y + 2 * halo_size)
padded_sz_dim = mtf.Dimension('padded_sz_block',
nc // n_block_z + 2 * halo_size)
kvec_hr = flowpm.kernels.fftk([
nc // n_block_x + 2 * halo_size, nc // n_block_y + 2 * halo_size,
nc // n_block_z + 2 * halo_size
],
symmetric=False)
kx_hr = mtf.import_tf_tensor(mesh,
kvec_hr[0].squeeze().astype('float32'),
shape=[padded_sx_dim])
ky_hr = mtf.import_tf_tensor(mesh,
kvec_hr[1].squeeze().astype('float32'),
shape=[padded_sy_dim])
kz_hr = mtf.import_tf_tensor(mesh,
kvec_hr[2].squeeze().astype('float32'),
shape=[padded_sz_dim])
kv_hr = [kx_hr, ky_hr, kz_hr]
lr_shape = [batch_dim, x_dim, y_dim, z_dim]
hr_shape = [batch_dim, nx_dim, ny_dim, nz_dim, sx_dim, sy_dim, sz_dim]
part_shape = [batch_dim, fx_dim, fy_dim, fz_dim]
initc = tf.reshape(
initial_conditions,
[1, n_block_x, nc // n_block_x, n_block_y, nc // n_block_y, 1, nc])
initc = tf.transpose(initc, [0, 1, 3, 5, 2, 4, 6])
field = mtf.import_tf_tensor(mesh, initc, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
field = mtf.pad(field, [halo_size, halo_size], block_size_dim.name)
for blocks_dim, block_size_dim in zip(hr_shape[1:4], field.shape[-3:]):
field = mpm.halo_reduce(field, blocks_dim, block_size_dim, halo_size)
field = mtf.reshape(field, field.shape + [mtf.Dimension('h_dim', 1)])
high = field
low = mesh_utils.downsample(field, downsampling_factor, antialias=True)
low = mtf.reshape(low, low.shape[:-1])
high = mtf.reshape(high, high.shape[:-1])
for block_size_dim in hr_shape[-3:]:
low = mtf.slice(low, halo_size // 2**downsampling_factor,
block_size_dim.size // 2**downsampling_factor,
block_size_dim.name)
# Hack usisng custom reshape because mesh is pretty dumb
low = mtf.slicewise(lambda x: x[:, 0, 0, 0], [low],
output_dtype=tf.float32,
output_shape=lr_shape,
name='my_dumb_reshape',
splittable_dims=lr_shape[:-1] + hr_shape[:4])
# Hack to handle reshape acrosss multiple dimensions
#low = mtf.reshape(low, [batch_dim, x_dim, low.shape[2], low.shape[5], z_dim])
#low = mtf.reshape(low, lr_shape)
state = mtfpm.lpt_init(
low,
high,
a0,
kv_lr,
kv_hr,
halo_size,
hr_shape,
lr_shape,
k_dims,
part_shape[1:],
downsampling_factor=downsampling_factor,
antialias=True,
)
# Here we can run our nbody
final_state = state #mtfpm.nbody(state, stages, lr_shape, hr_shape, k_dims, kv_lr, kv_hr, halo_size, downsampling_factor=downsampling_factor)
# paint the field
final_field = mtf.zeros(mesh, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
final_field = mtf.pad(final_field, [halo_size, halo_size],
block_size_dim.name)
final_field = mesh_utils.cic_paint(final_field, final_state[0], halo_size)
# Halo exchange
for blocks_dim, block_size_dim in zip(hr_shape[1:4],
final_field.shape[-3:]):
final_field = mpm.halo_reduce(final_field, blocks_dim, block_size_dim,
halo_size)
# Remove borders
for block_size_dim in hr_shape[-3:]:
final_field = mtf.slice(final_field, halo_size, block_size_dim.size,
block_size_dim.name)
#final_field = mtf.reshape(final_field, [batch_dim, fx_dim, fy_dim, fz_dim])
# Hack usisng custom reshape because mesh is pretty dumb
final_field = mtf.slicewise(
lambda x: x[:, 0, 0, 0], [final_field],
output_dtype=tf.float32,
output_shape=[batch_dim, fx_dim, fy_dim, fz_dim],
name='my_dumb_reshape',
splittable_dims=part_shape[:-1] + hr_shape[:4])
return final_field
def nbody_model(mesh):
"""
Initializes a 3D volume with random noise, and execute a forward FFT
"""
# Setup parameters
bs = FLAGS.box_size
nc = FLAGS.cube_size
batch_size = FLAGS.batch_size
a0 = FLAGS.a0
a = 1.0
nsteps = FLAGS.pm_steps
# Compute a few things first, using simple tensorflow
klin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[0]
plin = np.loadtxt('../flowpm/data/Planck15_a1p00.txt').T[1]
ipklin = iuspline(klin, plin)
stages = np.linspace(a0, a, nsteps, endpoint=True)
# Initialize the integration steps
stages = np.linspace(FLAGS.a0, 1.0, FLAGS.pm_steps, endpoint=True)
# Generate a batch of 3D initial conditions
initial_conditions = flowpm.linear_field(
nc, # size of the cube
bs, # Physical size of the cube
ipklin, # Initial power spectrum
batch_size=batch_size)
# Compute necessary Fourier kernels
kvec = flowpm.kernels.fftk((nc, nc, nc), symmetric=False)
from flowpm.kernels import laplace_kernel, gradient_kernel
lap = tf.cast(laplace_kernel(kvec), tf.complex64)
grad_x = gradient_kernel(kvec, 0)
grad_y = gradient_kernel(kvec, 1)
grad_z = gradient_kernel(kvec, 2)
# Define the named dimensions
# Parameters of the small scales decomposition
n_block_x = 8
n_block_y = 4
n_block_z = 1
halo_size = 16
# Parameters of the large scales decomposition
downsampling_factor = 2
lnc = nc // 2**downsampling_factor
fx_dim = mtf.Dimension("nx", nc)
fy_dim = mtf.Dimension("ny", nc)
fz_dim = mtf.Dimension("nz", nc)
# Dimensions of the low resolution grid
x_dim = mtf.Dimension("nx_lr", lnc)
y_dim = mtf.Dimension("ny_lr", lnc)
z_dim = mtf.Dimension("nz_lr", lnc)
x_dim_t = mtf.Dimension("x_lr_t", lnc)
y_dim_t = mtf.Dimension("y_lr_t", lnc)
z_dim_t = mtf.Dimension("z_lr_t", lnc)
nx_dim = mtf.Dimension('nx_block', n_block_x)
ny_dim = mtf.Dimension('ny_block', n_block_y)
nz_dim = mtf.Dimension('nz_block', n_block_z)
sx_dim = mtf.Dimension('sx_block', nc // n_block_x)
sy_dim = mtf.Dimension('sy_block', nc // n_block_y)
sz_dim = mtf.Dimension('sz_block', nc // n_block_z)
batch_dim = mtf.Dimension("batch", batch_size)
pk_dim = mtf.Dimension("npk", len(plin))
pk = mtf.import_tf_tensor(mesh, plin.astype('float32'), shape=[pk_dim])
# kvec for low resolution grid
kvec_lr = flowpm.kernels.fftk([lnc, lnc, lnc], symmetric=False)
kx_lr = mtf.import_tf_tensor(mesh,
kvec_lr[0].squeeze().astype('float32') /
2**downsampling_factor,
shape=[x_dim_t])
ky_lr = mtf.import_tf_tensor(mesh,
kvec_lr[1].squeeze().astype('float32') /
2**downsampling_factor,
shape=[y_dim_t])
kz_lr = mtf.import_tf_tensor(mesh,
kvec_lr[2].squeeze().astype('float32') /
2**downsampling_factor,
shape=[z_dim_t])
kv_lr = [ky_lr, kz_lr, kx_lr]
# kvec for high resolution blocks
padded_sx_dim = mtf.Dimension('padded_sx_block',
nc // n_block_x + 2 * halo_size)
padded_sy_dim = mtf.Dimension('padded_sy_block',
nc // n_block_y + 2 * halo_size)
padded_sz_dim = mtf.Dimension('padded_sz_block',
nc // n_block_z + 2 * halo_size)
kvec_hr = flowpm.kernels.fftk([
nc // n_block_x + 2 * halo_size, nc // n_block_y + 2 * halo_size,
nc // n_block_z + 2 * halo_size
],
symmetric=False)
kx_hr = mtf.import_tf_tensor(mesh,
kvec_hr[0].squeeze().astype('float32'),
shape=[padded_sx_dim])
ky_hr = mtf.import_tf_tensor(mesh,
kvec_hr[1].squeeze().astype('float32'),
shape=[padded_sy_dim])
kz_hr = mtf.import_tf_tensor(mesh,
kvec_hr[2].squeeze().astype('float32'),
shape=[padded_sz_dim])
kv_hr = [ky_hr, kz_hr, kx_hr]
lr_shape = [batch_dim, x_dim, y_dim, z_dim]
hr_shape = [batch_dim, nx_dim, ny_dim, nz_dim, sx_dim, sy_dim, sz_dim]
part_shape = [batch_dim, fx_dim, fy_dim, fz_dim]
initc = tf.reshape(initial_conditions, [
batch_size, n_block_x, nc // n_block_x, n_block_y, nc // n_block_y, 1,
nc
])
initc = tf.transpose(initc, [0, 1, 3, 5, 2, 4, 6])
field = mtf.import_tf_tensor(mesh, initc, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
field = mtf.pad(field, [halo_size, halo_size], block_size_dim.name)
for blocks_dim, block_size_dim in zip(hr_shape[1:4], field.shape[-3:]):
field = mpm.halo_reduce(field, blocks_dim, block_size_dim, halo_size)
field = mtf.reshape(field, field.shape + [mtf.Dimension('h_dim', 1)])
high = field
low = mesh_utils.downsample(field, downsampling_factor, antialias=True)
low = mtf.reshape(low, low.shape[:-1])
high = mtf.reshape(high, high.shape[:-1])
for block_size_dim in hr_shape[-3:]:
low = mtf.slice(low, halo_size // 2**downsampling_factor,
block_size_dim.size // 2**downsampling_factor,
block_size_dim.name)
# Hack usisng custom reshape because mesh is pretty dumb
low = mtf.slicewise(lambda x: x[:, 0, 0, 0], [low],
output_dtype=tf.float32,
output_shape=lr_shape,
name='my_dumb_reshape',
splittable_dims=lr_shape[:-1] + hr_shape[:4])
state = mtfpm.lpt_init(
low,
high,
0.1,
kv_lr,
kv_hr,
halo_size,
hr_shape,
lr_shape,
part_shape[1:],
downsampling_factor=downsampling_factor,
antialias=True,
)
# Here we can run our nbody
final_state = mtfpm.nbody(state,
stages,
lr_shape,
hr_shape,
kv_lr,
kv_hr,
halo_size,
downsampling_factor=downsampling_factor)
# paint the field
final_field = mtf.zeros(mesh, shape=hr_shape)
for block_size_dim in hr_shape[-3:]:
final_field = mtf.pad(final_field, [halo_size, halo_size],
block_size_dim.name)
final_field = mesh_utils.cic_paint(final_field, final_state[0], halo_size)
# Halo exchange
for blocks_dim, block_size_dim in zip(hr_shape[1:4],
final_field.shape[-3:]):
final_field = mpm.halo_reduce(final_field, blocks_dim, block_size_dim,
halo_size)
# Remove borders
for block_size_dim in hr_shape[-3:]:
final_field = mtf.slice(final_field, halo_size, block_size_dim.size,
block_size_dim.name)
#final_field = mtf.reshape(final_field, [batch_dim, fx_dim, fy_dim, fz_dim])
# Hack usisng custom reshape because mesh is pretty dumb
final_field = mtf.slicewise(
lambda x: x[:, 0, 0, 0], [final_field],
output_dtype=tf.float32,
output_shape=[batch_dim, fx_dim, fy_dim, fz_dim],
name='my_dumb_reshape',
splittable_dims=part_shape[:-1] + hr_shape[:4])
return final_field