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Add Spherical lensing example
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parent
2d21985279
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5 changed files with 1048 additions and 381 deletions
195
jaxpm/lensing.py
195
jaxpm/lensing.py
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@ -1,22 +1,32 @@
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import jax
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import jax.numpy as jnp
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import jax_cosmo
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import jax_cosmo as jc
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import jax_cosmo.constants as constants
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from jax.scipy.ndimage import map_coordinates
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from jaxpm.painting import cic_paint_2d
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from jaxpm.distributed import uniform_particles
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from jaxpm.painting import cic_paint, cic_paint_2d, cic_paint_dx
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from jaxpm.spherical import paint_spherical
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from jaxpm.utils import gaussian_smoothing
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def density_plane(positions,
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box_shape,
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center,
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width,
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plane_resolution,
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smoothing_sigma=None):
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""" Extacts a density plane from the simulation
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"""
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def density_plane_fn(box_shape,
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box_size,
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density_plane_width,
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density_plane_npix,
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sharding=None):
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def f(t, y, args):
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positions = y[0]
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cosmo = args
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nx, ny, nz = box_shape
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# Converts time t to comoving distance in voxel coordinates
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w = density_plane_width / box_size[2] * box_shape[2]
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center = jc.background.radial_comoving_distance(
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cosmo, t) / box_size[2] * box_shape[2]
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positions = uniform_particles(box_shape) + positions
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xy = positions[..., :2]
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d = positions[..., 2]
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@ -24,59 +34,148 @@ def density_plane(positions,
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xy = jnp.mod(xy, nx)
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# Rescaling positions to target grid
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xy = xy / nx * plane_resolution
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xy = xy / nx * density_plane_npix
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# Selecting only particles that fall inside the volume of interest
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weight = jnp.where(
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(d > (center - width / 2)) & (d <= (center + width / 2)), 1., 0.)
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weight = jnp.where((d > (center - w / 2)) & (d <= (center + w / 2)),
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1.0, 0.0)
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# Painting density plane
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density_plane = cic_paint_2d(
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jnp.zeros([plane_resolution, plane_resolution]), xy, weight)
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zero_mesh = jnp.zeros([density_plane_npix, density_plane_npix])
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# Apply sharding in order to recover sharding when taking gradients
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if sharding is not None:
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xy = jax.lax.with_sharding_constraint(xy, sharding)
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# Apply CIC painting
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density_plane = cic_paint_2d(zero_mesh, xy, weight)
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# Apply density normalization
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density_plane = density_plane / ((nx / plane_resolution) *
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(ny / plane_resolution) * (width))
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# Apply Gaussian smoothing if requested
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if smoothing_sigma is not None:
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density_plane = gaussian_smoothing(density_plane, smoothing_sigma)
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density_plane = density_plane / ((nx / density_plane_npix) *
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(ny / density_plane_npix) * w)
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return density_plane
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return f
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def convergence_Born(cosmo, density_planes, coords, z_source):
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def spherical_density_fn(box_shape,
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box_size,
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nside,
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fov,
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center_radec,
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observer_position,
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d_R,
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sharding=None):
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def f(t, y, args):
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positions = y[0]
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nx, ny, nz = box_shape
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bx, by, bz = box_size
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cosmo = args
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# Converts time t to comoving distance in voxel coordinates
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w = d_R / box_size[2] * box_shape[2]
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center = ((jc.background.radial_comoving_distance(cosmo, t)) / bz) * nz
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# Apply sharding in order to recover sharding when taking gradients
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if sharding is not None:
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positions = jax.lax.with_sharding_constraint(positions, sharding)
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density_mesh = cic_paint_dx(positions)
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# Project to spherical map
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spherical_map = paint_spherical(density_mesh, nside, fov, center_radec,
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observer_position, box_size, center,
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d_R)
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return spherical_map
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return f
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# ==========================================================
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# Weak Lensing Born Approximation
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# ==========================================================
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def convergence_Born(cosmo, density_planes, r, a, dx, dz, coords, z_source):
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"""
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Compute the Born convergence
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Args:
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cosmo: `Cosmology`, cosmology object.
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density_planes: list of dictionaries (r, a, density_plane, dx, dz), lens planes to use
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coords: a 3-D array of angular coordinates in radians of N points with shape [batch, N, 2].
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z_source: 1-D `Tensor` of source redshifts with shape [Nz] .
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name: `string`, name of the operation.
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Returns:
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`Tensor` of shape [batch_size, N, Nz], of convergence values.
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Compute Born-approximation lensing convergence maps.
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Parameters
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----------
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cosmo : jc.Cosmology
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Cosmology object.
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density_planes : ndarray
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3D array of lensing density planes [nx, ny, n_planes].
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r, a : ndarray
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Comoving distances and scale factors per plane.
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dx : float
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Pixel scale.
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dz : float
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Redshift bin width.
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coords : ndarray
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Angular coordinates grid [2, N, 2] in radians.
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z_source : ndarray
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Source redshifts.
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Returns
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-------
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convergence : ndarray
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2D convergence map for each source redshift.
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"""
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# Compute constant prefactor:
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constant_factor = 3 / 2 * cosmo.Omega_m * (constants.H0 / constants.c)**2
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# Compute comoving distance of source galaxies
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r_s = jax_cosmo.background.radial_comoving_distance(
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cosmo, 1 / (1 + z_source))
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r_s = jc.background.radial_comoving_distance(cosmo, 1 / (1 + z_source))
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n_planes = len(r)
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convergence = 0
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for entry in density_planes:
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r = entry['r']
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a = entry['a']
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p = entry['plane']
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dx = entry['dx']
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dz = entry['dz']
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# Normalize density planes
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density_normalization = dz * r / a
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def scan_fn(carry, i):
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density_planes, a, r = carry
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p = density_planes[:, :, i]
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density_normalization = dz * r[i] / a[i]
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p = (p - p.mean()) * constant_factor * density_normalization
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# Interpolate at the density plane coordinates
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im = map_coordinates(p, coords * r / dx - 0.5, order=1, mode="wrap")
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im = map_coordinates(p, coords * r[i] / dx - 0.5, order=1, mode="wrap")
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convergence += im * jnp.clip(1. -
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(r / r_s), 0, 1000).reshape([-1, 1, 1])
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return carry, im * jnp.clip(1.0 -
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(r[i] / r_s), 0, 1000).reshape([-1, 1, 1])
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return convergence
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_, convergence = jax.lax.scan(scan_fn, (density_planes, a, r),
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jnp.arange(n_planes))
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return convergence.sum(axis=0)
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def spherical_convergence_Born(cosmo, density_planes, r, a, nside, z_source):
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"""
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Compute Born-approximation lensing convergence maps on a sphere.
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Parameters
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----------
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cosmo : jc.Cosmology
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Cosmology object.
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density_planes : ndarray
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3D array of lensing density planes [n_planes, npix].
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r, a : ndarray
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Comoving distances and scale factors per plane.
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nside : int
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Healpix nside parameter.
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z_source : ndarray
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Source redshifts.
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Returns
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-------
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convergence : ndarray
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2D convergence map for each source redshift.
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"""
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constant_factor = 3 / 2 * cosmo.Omega_m * (constants.H0 / constants.c)**2
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# Compute comoving distance of source galaxies
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r_s = jc.background.radial_comoving_distance(cosmo, 1 / (1 + z_source))
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n_planes = len(r)
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def scan_fn(carry, i):
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density_planes, a, r = carry
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p = density_planes[i, :]
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density_normalization = r[i] / a[
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i] # This normalization needs to be checked
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p = (p - p.mean()) * constant_factor * density_normalization
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return carry, p * jnp.clip(1.0 -
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(r[i] / r_s), 0, 1000).reshape([-1, 1])
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_, convergence = jax.lax.scan(scan_fn, (density_planes, a, r),
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jnp.arange(n_planes))
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return convergence.sum(axis=0)
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133
jaxpm/ode.py
Normal file
133
jaxpm/ode.py
Normal file
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from jaxpm.growth import E, Gf, dGfa, gp
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from jaxpm.growth import growth_factor as Gp
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from jaxpm.pm import pm_forces
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def symplectic_fpm_ode(mesh_shape, dt0, paint_absolute_pos=True, halo_size=0, sharding=None):
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def drift(a, vel, args):
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"""
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state is a tuple (position, velocities)
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"""
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cosmo = args[0]
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# Get the time steps
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t0 = a
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t1 = a + dt0
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# Set the scale factors
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ai = t0
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ac = (t0 * t1) ** 0.5 # Geometric mean of t0 and t1
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af = t1
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#drift_contr = (Gp(cosmo, af) - Gp(cosmo, ai)) / gp(cosmo, ac)
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drift_contr = (af - ai )/ ac
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# Computes the update of position (drift)
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dpos = 1 / (ac**3 * E(cosmo, ac)) * vel
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return dpos * (drift_contr / dt0)
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def kick(a, pos, args):
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"""
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state is a tuple (position, velocities)
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"""
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# Computes the update of velocity (kick)
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cosmo = args
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# Get the time steps
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t0 = a
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t1 = t0 + dt0
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t2 = t1 + dt0
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t0t1 = (t0 * t1) ** 0.5 # Geometric mean of t0 and t1
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t1t2 = (t1 * t2) ** 0.5 # Geometric mean of t1 and t2
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# Set the scale factors
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ac = t1
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forces = (
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pm_forces(
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pos,
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mesh_shape=mesh_shape,
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paint_absolute_pos=paint_absolute_pos,
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halo_size=halo_size,
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sharding=sharding,
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)
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* 1.5
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* cosmo.Omega_m
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)
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# Computes the update of velocity (kick)
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dvel = 1.0 / (ac**2 * E(cosmo, ac)) * forces
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# First kick control factor
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kick_factor_1 = (t1 - t0t1) / t1
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#kick_factor_1 = (Gf(cosmo, t1) - Gf(cosmo, t0t1)) / dGfa(cosmo, t1)
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# Second kick control factor
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kick_factor_2 = (t2 - t1t2) / t2
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#kick_factor_2 = (Gf(cosmo, t1t2) - Gf(cosmo, t1)) / dGfa(cosmo, t1)
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return dvel * ((kick_factor_1 + kick_factor_2) / dt0)
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def first_kick(a, pos, args):
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"""
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state is a tuple (position, velocities)
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"""
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# Computes the update of velocity (kick)
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cosmo = args
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# Get the time steps
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t0 = a
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t1 = t0 + dt0
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t0t1 = (t0 * t1) ** 0.5 # Geometric mean of t0 and t1
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forces = (
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pm_forces(
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pos,
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mesh_shape=mesh_shape,
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paint_absolute_pos=paint_absolute_pos,
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halo_size=halo_size,
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sharding=sharding,
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)
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* 1.5
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* cosmo.Omega_m
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)
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# Computes the update of velocity (kick)
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dvel = 1.0 / (a**2 * E(cosmo, a)) * forces
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# First kick control factor
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kick_factor = (Gf(cosmo, t0t1) - Gf(cosmo, t0)) / dGfa(cosmo, t0)
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return dvel * (kick_factor / dt0)
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return drift, kick, first_kick
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def symplectic_ode(mesh_shape, paint_absolute_pos=True, halo_size=0, sharding=None):
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def drift(a, vel, args):
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"""
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state is a tuple (position, velocities)
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"""
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cosmo = args
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# Computes the update of position (drift)
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dpos = 1 / (a**3 * E(cosmo, a)) * vel
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return dpos
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def kick(a, pos, args):
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"""
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state is a tuple (position, velocities)
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"""
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# Computes the update of velocity (kick)
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cosmo = args
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forces = (
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pm_forces(
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pos,
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mesh_shape=mesh_shape,
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paint_absolute_pos=paint_absolute_pos,
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halo_size=halo_size,
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sharding=sharding,
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)
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* 1.5
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* cosmo.Omega_m
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)
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# Computes the update of velocity (kick)
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dvel = 1.0 / (a**2 * E(cosmo, a)) * forces
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return dvel
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return drift, kick
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50
jaxpm/spherical.py
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50
jaxpm/spherical.py
Normal file
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import jax.numpy as jnp
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import jax_healpy as jhp
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import matplotlib.pyplot as plt
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import jax
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from functools import partial
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import healpy as hp
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@partial(jax.jit, static_argnames=('nside', 'fov', 'center_radec' , 'd_R' , 'box_size'))
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def paint_spherical(volume, nside, fov, center_radec, observer_position, box_size, R, d_R):
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width, height, depth = volume.shape
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ra0, dec0 = center_radec
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fov_width, fov_height = fov
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pixel_scale_x = fov_width / width
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pixel_scale_y = fov_height / height
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res_deg = jhp.nside2resol(nside, arcmin=True) / 60
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if pixel_scale_x > res_deg or pixel_scale_y > res_deg:
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print(f"WARNING Pixel scale ({pixel_scale_x:.4f} deg, {pixel_scale_y:.4f} deg) is larger than the Healpy resolution ({res_deg:.4f} deg). Increase the field of view or decrease the nside.")
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y_idx, x_idx = jnp.indices((height, width))
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ra_grid = ra0 + x_idx * pixel_scale_x
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dec_grid = dec0 + y_idx * pixel_scale_y
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ra_flat = ra_grid.flatten() * jnp.pi / 180.0
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dec_flat = dec_grid.flatten() * jnp.pi / 180.0
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R_s = jnp.arange(0 , d_R, 1.0) + R
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XYZ = R_s.reshape(-1, 1, 1) * jhp.ang2vec(ra_flat, dec_flat, lonlat=False)
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observer_position = jnp.array(observer_position)
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# Convert observer position from box units to grid units
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observer_position = observer_position / jnp.array(box_size) * jnp.array(volume.shape)
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coords = XYZ + jnp.asarray(observer_position)[jnp.newaxis, jnp.newaxis, :]
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pixels = jhp.ang2pix(nside, ra_flat, dec_flat, lonlat=False)
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npix = jhp.nside2npix(nside)
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@partial(jax.vmap, in_axes=(0, None, None))
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def interpolate_volume(coords, volume, pixels):
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voxels = jax.scipy.ndimage.map_coordinates(volume, coords.T, order=1)
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sums = jnp.bincount(pixels, weights=voxels, length=npix)
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return sums
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sum_map = interpolate_volume(coords, volume, pixels).sum(axis=0)
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counts = jnp.bincount(pixels, length=npix)
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sum_map = jnp.where(counts > 0, sum_map / counts, jhp.UNSEEN)
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return sum_map
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@ -1,320 +0,0 @@
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{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"# **Animating Particle Mesh density fields**\n",
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"\n",
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"In this tutorial, we will animate the density field of a particle mesh simulation. We will use the `manim` library to create the animation. \n",
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"\n",
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"The density fields are created exactly like in the notebook [**05-MultiHost_PM.ipynb**](05-MultiHost_PM.ipynb) using the same script [**05-MultiHost_PM.py**](05-MultiHost_PM.py)."
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"To run a multi-host simulation, you first need to **allocate a job** with `salloc`. This command requests resources on an HPC cluster.\n",
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"\n",
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"just like in notebook [**05-MultiHost_PM.ipynb**]"
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"!salloc --account=XXX@a100 -C a100 --gres=gpu:8 --ntasks-per-node=8 --time=00:40:00 --cpus-per-task=8 --hint=nomultithread --qos=qos_gpu-dev --nodes=4 & "
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]
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},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"**A few hours later**\n",
|
||||
"\n",
|
||||
"Use `!squeue -u $USER -o \"%i %D %b\"` to **check the JOB ID** and verify your resource allocation.\n",
|
||||
"\n",
|
||||
"In this example, we’ve been allocated **32 GPUs split across 4 nodes**.\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"!squeue -u $USER -o \"%i %D %b\""
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"Unset the following environment variables, as they can cause issues when using JAX in a distributed setting:"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"import os\n",
|
||||
"del os.environ['VSCODE_PROXY_URI']\n",
|
||||
"del os.environ['NO_PROXY']\n",
|
||||
"del os.environ['no_proxy']"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Checking Available Compute Resources\n",
|
||||
"\n",
|
||||
"Run the following command to initialize JAX distributed computing and display the devices available for this job:\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"!srun --jobid=467745 -n 32 python -c \"import jax; jax.distributed.initialize(); print(jax.devices()) if jax.process_index() == 0 else None\""
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Multi-Host Simulation Script with Arguments (reminder)\n",
|
||||
"\n",
|
||||
"This script is nearly identical to the single-host version, with the main addition being the call to `jax.distributed.initialize()` at the start, enabling multi-host parallelism. Here’s a breakdown of the key arguments:\n",
|
||||
"\n",
|
||||
"- **`--pdims`** (`-p`): Specifies processor grid dimensions as two integers, like `16 2` for 16 x 2 device mesh (default is `[1, jax.devices()]`).\n",
|
||||
"- **`--mesh_shape`** (`-m`): Defines the simulation mesh shape as three integers (default is `[512, 512, 512]`).\n",
|
||||
"- **`--box_size`** (`-b`): Sets the physical box size of the simulation as three floating-point values, e.g., `1000. 1000. 1000.` (default is `[500.0, 500.0, 500.0]`).\n",
|
||||
"- **`--halo_size`** (`-H`): Specifies the halo size for boundary overlap across nodes (default is `64`).\n",
|
||||
"- **`--solver`** (`-s`): Chooses the ODE solver (`leapfrog` or `dopri8`). The `leapfrog` solver uses a fixed step size, while `dopri8` is an adaptive Runge-Kutta solver with a PID controller (default is `leapfrog`).\n",
|
||||
"- **`--snapthots`** (`-st`) : Number of snapshots to save (warning, increases memory usage)\n",
|
||||
"\n",
|
||||
"### Running the Multi-Host Simulation Script\n",
|
||||
"\n",
|
||||
"To create a smooth animation, we need a series of closely spaced snapshots to capture the evolution of the density field over time. In this example, we set the number of snapshots to **10** to ensure smooth transitions in the animation.\n",
|
||||
"\n",
|
||||
"Using a larger number of GPUs helps process these snapshots efficiently, especially with a large simulation mesh or high-resolution data. This allows us to achieve both the desired snapshot frequency and the necessary simulation detail without excessive runtime.\n",
|
||||
"\n",
|
||||
"The command to run the multi-host simulation with these settings will look something like this:\n",
|
||||
"\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"import subprocess\n",
|
||||
"\n",
|
||||
"# Define parameters as variables\n",
|
||||
"jobid = \"467745\"\n",
|
||||
"num_processes = 32\n",
|
||||
"script_name = \"05-MultiHost_PM.py\"\n",
|
||||
"mesh_shape = (1024, 1024, 1024)\n",
|
||||
"box_size = (1000., 1000., 1000.)\n",
|
||||
"halo_size = 128\n",
|
||||
"solver = \"leapfrog\"\n",
|
||||
"pdims = (16, 2)\n",
|
||||
"snapshots = 8\n",
|
||||
"\n",
|
||||
"# Build the command as a list, incorporating variables\n",
|
||||
"command = [\n",
|
||||
" \"srun\",\n",
|
||||
" f\"--jobid={jobid}\",\n",
|
||||
" \"-n\", str(num_processes),\n",
|
||||
" \"python\", script_name,\n",
|
||||
" \"--mesh_shape\", str(mesh_shape[0]), str(mesh_shape[1]), str(mesh_shape[2]),\n",
|
||||
" \"--box_size\", str(box_size[0]), str(box_size[1]), str(box_size[2]),\n",
|
||||
" \"--halo_size\", str(halo_size),\n",
|
||||
" \"-s\", solver,\n",
|
||||
" \"--pdims\", str(pdims[0]), str(pdims[1]),\n",
|
||||
" \"--snapshots\", str(snapshots)\n",
|
||||
"]\n",
|
||||
"\n",
|
||||
"# Execute the command as a subprocess\n",
|
||||
"subprocess.run(command)\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Projecting the 3D Density Fields to 2D\n",
|
||||
"\n",
|
||||
"To visualize the 3D density fields in 2D, we need to create a projection:\n",
|
||||
"\n",
|
||||
"- **`project_to_2d` Function**: This function reduces the 3D array to 2D by summing over a portion of one axis.\n",
|
||||
" - We sum the top one-eighth of the data along the first axis to capture a slice of the density field.\n",
|
||||
"\n",
|
||||
"- **Creating 2D Projections**: Apply `project_to_2d` to each 3D field (`initial_conditions`, `lpt_displacements`, `ode_solution_0`, and `ode_solution_1`) to get 2D arrays that represent the density fields.\n",
|
||||
"\n",
|
||||
"### Applying the Magma Colormap\n",
|
||||
"\n",
|
||||
"To improve visualization, apply the \"magma\" colormap to each 2D projection:\n",
|
||||
"\n",
|
||||
"- **`apply_colormap` Function**: This function maps values in the 2D array to colors using the \"magma\" colormap.\n",
|
||||
" - First, normalize the array to the `[0, 1]` range.\n",
|
||||
" - Apply the colormap to create RGB images, which will be used for the animation.\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": 1,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"from matplotlib import colormaps\n",
|
||||
"\n",
|
||||
"# Define a function to project the 3D field to 2D\n",
|
||||
"def project_to_2d(field):\n",
|
||||
" sum_over = field.shape[0] // 8\n",
|
||||
" slicing = [slice(None)] * field.ndim\n",
|
||||
" slicing[0] = slice(None, sum_over)\n",
|
||||
" slicing = tuple(slicing)\n",
|
||||
"\n",
|
||||
" return field[slicing].sum(axis=0)\n",
|
||||
"\n",
|
||||
"\n",
|
||||
"def apply_colormap(array, cmap_name=\"magma\"):\n",
|
||||
" cmap = colormaps[cmap_name]\n",
|
||||
" normalized_array = (array - array.min()) / (array.max() - array.min())\n",
|
||||
" colored_image = cmap(normalized_array)[:, :, :3] # Drop alpha channel for RGB\n",
|
||||
" return (colored_image * 255).astype(np.uint8)\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Loading and Visualizing Results\n",
|
||||
"\n",
|
||||
"After running the multi-host simulation, we load the saved results from disk:\n",
|
||||
"\n",
|
||||
"- **`initial_conditions.npy`**: Initial conditions for the simulation.\n",
|
||||
"- **`lpt_displacements.npy`**: Linear perturbation displacements.\n",
|
||||
"- **`ode_solution_*.npy`** : Solutions from the ODE solver at each snapshot.\n",
|
||||
"\n",
|
||||
"We will now project the fields to 2D maps and apply the color map\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": 2,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"import numpy as np\n",
|
||||
"\n",
|
||||
"initial_conditions = apply_colormap(project_to_2d(np.load('fields/initial_conditions.npy')))\n",
|
||||
"lpt_displacements = apply_colormap(project_to_2d(np.load('fields/lpt_displacements.npy')))\n",
|
||||
"ode_solutions = []\n",
|
||||
"for i in range(8):\n",
|
||||
" ode_solutions.append(apply_colormap(project_to_2d(np.load(f'fields/ode_solution_{i}.npy'))))"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Animating with Manim\n",
|
||||
"\n",
|
||||
"To create animations with `manim` in a Jupyter notebook, we start by configuring some settings to ensure the output displays correctly and without a background.\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": 3,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"from manim import *\n",
|
||||
"config.media_width = \"100%\"\n",
|
||||
"config.verbosity = \"WARNING\"\n",
|
||||
"config.background_color = \"#00000000\" # Transparent background"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "markdown",
|
||||
"metadata": {},
|
||||
"source": [
|
||||
"### Defining the Animation in Manim\n",
|
||||
"\n",
|
||||
"This animation class, `FieldTransition`, smoothly transitions through the stages of the particle mesh density field evolution.\n",
|
||||
"\n",
|
||||
"- **Setup**: Each density field snapshot is loaded as an image and aligned for smooth transitions.\n",
|
||||
"- **Animation Sequence**:\n",
|
||||
" - The animation begins with a fade-in of the initial conditions.\n",
|
||||
" - It then transitions through the stages in sequence, showing each snapshot of the density field evolution with brief pauses in between.\n",
|
||||
"\n",
|
||||
"To run the animation, execute `%manim -v WARNING -qm FieldTransition` to render it in the Jupyter Notebook.\n"
|
||||
]
|
||||
},
|
||||
{
|
||||
"cell_type": "code",
|
||||
"execution_count": null,
|
||||
"metadata": {},
|
||||
"outputs": [],
|
||||
"source": [
|
||||
"# Define the animation in Manim\n",
|
||||
"class FieldTransition(Scene):\n",
|
||||
" def construct(self):\n",
|
||||
" init_conditions_img = ImageMobject(initial_conditions).scale(4)\n",
|
||||
" lpt_img = ImageMobject(lpt_displacements).scale(4)\n",
|
||||
" snapshots_imgs = [ImageMobject(sol).scale(4) for sol in ode_solutions]\n",
|
||||
"\n",
|
||||
"\n",
|
||||
" # Place the images on top of each other initially\n",
|
||||
" lpt_img.move_to(init_conditions_img)\n",
|
||||
" for img in snapshots_imgs:\n",
|
||||
" img.move_to(init_conditions_img)\n",
|
||||
"\n",
|
||||
" # Show initial field and then transform between fields\n",
|
||||
" self.play(FadeIn(init_conditions_img))\n",
|
||||
" self.wait(0.2)\n",
|
||||
" self.play(Transform(init_conditions_img, lpt_img))\n",
|
||||
" self.wait(0.2)\n",
|
||||
" self.play(Transform(lpt_img, snapshots_imgs[0]))\n",
|
||||
" self.wait(0.2)\n",
|
||||
" for img1, img2 in zip(snapshots_imgs, snapshots_imgs[1:]):\n",
|
||||
" self.play(Transform(img1, img2))\n",
|
||||
" self.wait(0.2)\n",
|
||||
"\n",
|
||||
"%manim -v WARNING -qm -o anim.gif --format=gif FieldTransition "
|
||||
]
|
||||
}
|
||||
],
|
||||
"metadata": {
|
||||
"kernelspec": {
|
||||
"display_name": "Python 3",
|
||||
"language": "python",
|
||||
"name": "python3"
|
||||
},
|
||||
"language_info": {
|
||||
"codemirror_mode": {
|
||||
"name": "ipython",
|
||||
"version": 3
|
||||
},
|
||||
"file_extension": ".py",
|
||||
"mimetype": "text/x-python",
|
||||
"name": "python",
|
||||
"nbconvert_exporter": "python",
|
||||
"pygments_lexer": "ipython3",
|
||||
"version": "3.10.4"
|
||||
}
|
||||
},
|
||||
"nbformat": 4,
|
||||
"nbformat_minor": 2
|
||||
}
|
705
notebooks/06-RayTracing.ipynb
Normal file
705
notebooks/06-RayTracing.ipynb
Normal file
File diff suppressed because one or more lines are too long
Loading…
Add table
Add a link
Reference in a new issue