def load_octree(
octree_mask,
data,
bbox=None,
sim_time=0.0,
length_unit=None,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(True, True, True),
over_refine_factor=1,
partial_coverage=1,
unit_system="cgs",
):
r"""Load an octree mask into yt.
Octrees can be saved out by calling save_octree on an OctreeContainer.
This enables them to be loaded back in.
This will initialize an Octree of data. Note that fluid fields will not
work yet, or possibly ever.
Parameters
----------
octree_mask : np.ndarray[uint8_t]
This is a depth-first refinement mask for an Octree. It should be
of size n_octs * 8 (but see note about the root oct below), where
each item is 1 for an oct-cell being refined and 0 for it not being
refined. For over_refine_factors != 1, the children count will
still be 8, so there will stil be n_octs * 8 entries. Note that if
the root oct is not refined, there will be only one entry
for the root, so the size of the mask will be (n_octs - 1)*8 + 1.
data : dict
A dictionary of 1D arrays. Note that these must of the size of the
number of "False" values in the ``octree_mask``.
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units of length
sim_time : float, optional
The simulation time in seconds
length_unit : string
Unit to use for lengths. Defaults to unitless.
mass_unit : string
Unit to use for masses. Defaults to unitless.
time_unit : string
Unit to use for times. Defaults to unitless.
velocity_unit : string
Unit to use for velocities. Defaults to unitless.
magnetic_unit : string
Unit to use for magnetic fields. Defaults to unitless.
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
partial_coverage : boolean
Whether or not an oct can be refined cell-by-cell, or whether all
8 get refined.
Example
-------
>>> import numpy as np
>>> oct_mask = [8, 0, 0, 0, 0, 8, 0, 8,
... 0, 0, 0, 0, 0, 0, 0, 0,
... 8, 0, 0, 0, 0, 0, 0, 0,
... 0]
>>>
>>> octree_mask = np.array(oct_mask, dtype=np.uint8)
>>> quantities = {}
>>> quantities['gas', 'density'] = np.random.random((22, 1))
>>> bbox = np.array([[-10., 10.], [-10., 10.], [-10., 10.]])
>>>
>>> ds = load_octree(octree_mask=octree_mask,
... data=quantities,
... bbox=bbox,
... over_refine_factor=0,
... partial_coverage=0)
"""
from yt.frontends.stream.data_structures import (
StreamDictFieldHandler,
StreamHandler,
StreamOctreeDataset,
)
from yt.frontends.stream.definitions import process_data, set_particle_types
if not isinstance(octree_mask, np.ndarray) or octree_mask.dtype != np.uint8:
raise TypeError("octree_mask should be a Numpy array with type uint8")
nz = 1 << (over_refine_factor)
domain_dimensions = np.array([nz, nz, nz])
nprocs = 1
if bbox is None:
bbox = np.array([[0.0, 1.0], [0.0, 1.0], [0.0, 1.0]], "float64")
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros(nprocs, dtype="int32").reshape((nprocs, 1))
field_units, data, _ = process_data(data)
sfh = StreamDictFieldHandler()
particle_types = set_particle_types(data)
sfh.update({0: data})
grid_left_edges = domain_left_edge
grid_right_edges = domain_right_edge
grid_dimensions = domain_dimensions.reshape(nprocs, 3).astype("int32")
if length_unit is None:
length_unit = "code_length"
if mass_unit is None:
mass_unit = "code_mass"
if time_unit is None:
time_unit = "code_time"
if velocity_unit is None:
velocity_unit = "code_velocity"
if magnetic_unit is None:
magnetic_unit = "code_magnetic"
# I'm not sure we need any of this.
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
-np.ones(nprocs, dtype="int64"),
np.zeros(nprocs, dtype="int64").reshape(nprocs, 1), # Temporary
np.zeros(nprocs).reshape((nprocs, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "OctreeData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = 2
handler.dimensionality = 3
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamOctreeDataset(handler, unit_system=unit_system)
sds.octree_mask = octree_mask
sds.partial_coverage = partial_coverage
sds.over_refine_factor = over_refine_factor
return sds
def load_hexahedral_mesh(
data,
connectivity,
coordinates,
length_unit=None,
bbox=None,
sim_time=0.0,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(True, True, True),
geometry="cartesian",
unit_system="cgs",
):
r"""Load a hexahedral mesh of data into yt as a
:class:`~yt.frontends.stream.data_structures.StreamHandler`.
This should allow a semistructured grid of data to be loaded directly into
yt and analyzed as would any others. This comes with several caveats:
* Units will be incorrect unless the data has already been converted to
cgs.
* Some functions may behave oddly, and parallelism will be
disappointing or non-existent in most cases.
* Particles may be difficult to integrate.
Particle fields are detected as one-dimensional fields. The number of particles
is set by the "number_of_particles" key in data.
Parameters
----------
data : dict
This is a dict of numpy arrays, where the keys are the field names.
There must only be one. Note that the data in the numpy arrays should
define the cell-averaged value for of the quantity in in the hexahedral
cell.
connectivity : array_like
This should be of size (N,8) where N is the number of zones.
coordinates : array_like
This should be of size (M,3) where M is the number of vertices
indicated in the connectivity matrix.
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units of the length unit.
sim_time : float, optional
The simulation time in seconds
mass_unit : string
Unit to use for masses. Defaults to unitless.
time_unit : string
Unit to use for times. Defaults to unitless.
velocity_unit : string
Unit to use for velocities. Defaults to unitless.
magnetic_unit : string
Unit to use for magnetic fields. Defaults to unitless.
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
geometry : string or tuple
"cartesian", "cylindrical", "polar", "spherical", "geographic" or
"spectral_cube". Optionally, a tuple can be provided to specify the
axis ordering -- for instance, to specify that the axis ordering should
be z, x, y, this would be: ("cartesian", ("z", "x", "y")). The same
can be done for other coordinates, for instance:
("spherical", ("theta", "phi", "r")).
"""
from yt.frontends.stream.data_structures import (
StreamDictFieldHandler,
StreamHandler,
StreamHexahedralDataset,
)
from yt.frontends.stream.definitions import process_data, set_particle_types
domain_dimensions = np.ones(3, "int32") * 2
nprocs = 1
if bbox is None:
bbox = np.array([[0.0, 1.0], [0.0, 1.0], [0.0, 1.0]], "float64")
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros(nprocs, dtype="int32").reshape((nprocs, 1))
field_units, data, _ = process_data(data)
sfh = StreamDictFieldHandler()
particle_types = set_particle_types(data)
sfh.update({"connectivity": connectivity, "coordinates": coordinates, 0: data})
# Simple check for axis length correctness
if len(data) > 0:
fn = list(sorted(data))[0]
array_values = data[fn]
if array_values.size != connectivity.shape[0]:
mylog.error(
"Dimensions of array must be one fewer than the coordinate set."
)
raise RuntimeError
grid_left_edges = domain_left_edge
grid_right_edges = domain_right_edge
grid_dimensions = domain_dimensions.reshape(nprocs, 3).astype("int32")
if length_unit is None:
length_unit = "code_length"
if mass_unit is None:
mass_unit = "code_mass"
if time_unit is None:
time_unit = "code_time"
if velocity_unit is None:
velocity_unit = "code_velocity"
if magnetic_unit is None:
magnetic_unit = "code_magnetic"
# I'm not sure we need any of this.
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
-np.ones(nprocs, dtype="int64"),
np.zeros(nprocs, dtype="int64").reshape(nprocs, 1), # Temporary
np.zeros(nprocs).reshape((nprocs, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "HexahedralMeshData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = 2
handler.dimensionality = 3
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamHexahedralDataset(handler, geometry=geometry, unit_system=unit_system)
return sds
def load_particles(
data,
length_unit=None,
bbox=None,
sim_time=None,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(True, True, True),
geometry="cartesian",
unit_system="cgs",
data_source=None,
):
r"""Load a set of particles into yt as a
:class:`~yt.frontends.stream.data_structures.StreamParticleHandler`.
This will allow a collection of particle data to be loaded directly into
yt and analyzed as would any others. This comes with several caveats:
* There must be sufficient space in memory to contain all the particle
data.
* Parallelism will be disappointing or non-existent in most cases.
* Fluid fields are not supported.
Note: in order for the dataset to take advantage of SPH functionality,
the following two fields must be provided:
* ('io', 'density')
* ('io', 'smoothing_length')
Parameters
----------
data : dict
This is a dict of numpy arrays or (numpy array, unit name) tuples,
where the keys are the field names. Particles positions must be named
"particle_position_x", "particle_position_y", and "particle_position_z".
length_unit : float
Conversion factor from simulation length units to centimeters
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units of the length_unit
sim_time : float, optional
The simulation time in seconds
mass_unit : float
Conversion factor from simulation mass units to grams
time_unit : float
Conversion factor from simulation time units to seconds
velocity_unit : float
Conversion factor from simulation velocity units to cm/s
magnetic_unit : float
Conversion factor from simulation magnetic units to gauss
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
data_source : YTSelectionContainer, optional
If set, parameters like `bbox`, `sim_time`, and code units are derived
from it.
Examples
--------
>>> pos = [np.random.random(128*128*128) for i in range(3)]
>>> data = dict(particle_position_x = pos[0],
... particle_position_y = pos[1],
... particle_position_z = pos[2])
>>> bbox = np.array([[0., 1.0], [0.0, 1.0], [0.0, 1.0]])
>>> ds = load_particles(data, 3.08e24, bbox=bbox)
"""
from yt.frontends.stream.data_structures import (
StreamDictFieldHandler,
StreamHandler,
StreamParticlesDataset,
)
from yt.frontends.stream.definitions import process_data, set_particle_types
domain_dimensions = np.ones(3, "int32")
nprocs = 1
# Parse bounding box
if data_source is not None:
le, re = data_source.get_bbox()
le = le.to_value("code_length")
re = re.to_value("code_length")
bbox = list(zip(le, re))
if bbox is None:
bbox = np.array([[0.0, 1.0], [0.0, 1.0], [0.0, 1.0]], "float64")
else:
bbox = np.array(bbox)
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros(nprocs, dtype="int32").reshape((nprocs, 1))
# Parse simulation time
if data_source is not None:
sim_time = data_source.ds.current_time
if sim_time is None:
sim_time = 0.0
else:
sim_time = float(sim_time)
# Parse units
def parse_unit(unit, dimension):
if unit is None:
unit = "code_" + dimension
if data_source is not None:
unit = getattr(data_source.ds, dimension + "_unit", unit)
return unit
length_unit = parse_unit(length_unit, "length")
mass_unit = parse_unit(mass_unit, "mass")
time_unit = parse_unit(time_unit, "time")
velocity_unit = parse_unit(velocity_unit, "velocity")
magnetic_unit = parse_unit(magnetic_unit, "magnetic")
# Preprocess data
field_units, data, _ = process_data(data)
sfh = StreamDictFieldHandler()
pdata = {}
for key in data.keys():
if not isinstance(key, tuple):
field = ("io", key)
mylog.debug("Reassigning '%s' to '%s'", key, field)
else:
field = key
pdata[field] = data[key]
sfh._additional_fields += (field,)
data = pdata # Drop reference count
particle_types = set_particle_types(data)
sfh.update({"stream_file": data})
grid_left_edges = domain_left_edge
grid_right_edges = domain_right_edge
grid_dimensions = domain_dimensions.reshape(nprocs, 3).astype("int32")
# I'm not sure we need any of this.
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
-np.ones(nprocs, dtype="int64"),
np.zeros(nprocs, dtype="int64").reshape(nprocs, 1), # Temporary
np.zeros(nprocs).reshape((nprocs, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "ParticleData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = 2
handler.dimensionality = 3
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamParticlesDataset(handler, geometry=geometry, unit_system=unit_system)
return sds
def load_amr_grids(
grid_data,
domain_dimensions,
bbox=None,
sim_time=0.0,
length_unit=None,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(True, True, True),
geometry="cartesian",
refine_by=2,
unit_system="cgs",
):
r"""Load a set of grids of data into yt as a
:class:`~yt.frontends.stream.data_structures.StreamHandler`.
This should allow a sequence of grids of varying resolution of data to be
loaded directly into yt and analyzed as would any others. This comes with
several caveats:
* Units will be incorrect unless the unit system is explicitly specified.
* Some functions may behave oddly, and parallelism will be
disappointing or non-existent in most cases.
* Particles may be difficult to integrate.
* No consistency checks are performed on the index
Parameters
----------
grid_data : list of dicts
This is a list of dicts. Each dict must have entries "left_edge",
"right_edge", "dimensions", "level", and then any remaining entries are
assumed to be fields. Field entries must map to an NDArray. The grid_data
may also include a particle count. If no particle count is supplied, the
dataset is understood to contain no particles. The grid_data will be
modified in place and can't be assumed to be static.
domain_dimensions : array_like
This is the domain dimensions of the grid
length_unit : string or float
Unit to use for lengths. Defaults to unitless. If set to be a string, the bbox
dimensions are assumed to be in the corresponding units. If set to a float, the
value is a assumed to be the conversion from bbox dimensions to centimeters.
mass_unit : string or float
Unit to use for masses. Defaults to unitless.
time_unit : string or float
Unit to use for times. Defaults to unitless.
velocity_unit : string or float
Unit to use for velocities. Defaults to unitless.
magnetic_unit : string or float
Unit to use for magnetic fields. Defaults to unitless.
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units specified by length_unit.
Defaults to a cubic unit-length domain.
sim_time : float, optional
The simulation time in seconds
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
geometry : string or tuple
"cartesian", "cylindrical", "polar", "spherical", "geographic" or
"spectral_cube". Optionally, a tuple can be provided to specify the
axis ordering -- for instance, to specify that the axis ordering should
be z, x, y, this would be: ("cartesian", ("z", "x", "y")). The same
can be done for other coordinates, for instance:
("spherical", ("theta", "phi", "r")).
refine_by : integer or list/array of integers.
Specifies the refinement ratio between levels. Defaults to 2. This
can be an array, in which case it specifies for each dimension. For
instance, this can be used to say that some datasets have refinement of
1 in one dimension, indicating that they span the full range in that
dimension.
Examples
--------
>>> grid_data = [
... dict(left_edge = [0.0, 0.0, 0.0],
... right_edge = [1.0, 1.0, 1.],
... level = 0,
... dimensions = [32, 32, 32],
... number_of_particles = 0),
... dict(left_edge = [0.25, 0.25, 0.25],
... right_edge = [0.75, 0.75, 0.75],
... level = 1,
... dimensions = [32, 32, 32],
... number_of_particles = 0)
... ]
...
>>> for g in grid_data:
... g["density"] = (np.random.random(g["dimensions"])*2**g["level"], "g/cm**3")
...
>>> ds = load_amr_grids(grid_data, [32, 32, 32], length_unit=1.0)
"""
from yt.frontends.stream.data_structures import (
StreamDataset,
StreamDictFieldHandler,
StreamHandler,
)
from yt.frontends.stream.definitions import process_data, set_particle_types
domain_dimensions = np.array(domain_dimensions)
ngrids = len(grid_data)
if bbox is None:
bbox = np.array([[0.0, 1.0], [0.0, 1.0], [0.0, 1.0]], "float64")
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros((ngrids, 1), dtype="int32")
grid_left_edges = np.zeros((ngrids, 3), dtype="float64")
grid_right_edges = np.zeros((ngrids, 3), dtype="float64")
grid_dimensions = np.zeros((ngrids, 3), dtype="int32")
number_of_particles = np.zeros((ngrids, 1), dtype="int64")
parent_ids = np.zeros(ngrids, dtype="int64") - 1
sfh = StreamDictFieldHandler()
for i, g in enumerate(grid_data):
grid_left_edges[i, :] = g.pop("left_edge")
grid_right_edges[i, :] = g.pop("right_edge")
grid_dimensions[i, :] = g.pop("dimensions")
grid_levels[i, :] = g.pop("level")
# If someone included this throw it away--old API
if "number_of_particles" in g:
issue_deprecation_warning(
"It is no longer necessary to include "
"the number of particles in the data "
"dict. The number of particles is "
"determined from the sizes of the "
"particle fields.",
since="4.0.0",
removal="4.1.0",
)
g.pop("number_of_particles")
field_units, data, n_particles = process_data(
g, grid_dims=tuple(grid_dimensions[i, :])
)
number_of_particles[i, :] = n_particles
sfh[i] = data
# We now reconstruct our parent ids, so that our particle assignment can
# proceed.
mask = np.empty(ngrids, dtype="int32")
for gi in range(ngrids):
get_box_grids_level(
grid_left_edges[gi, :],
grid_right_edges[gi, :],
grid_levels[gi] + 1,
grid_left_edges,
grid_right_edges,
grid_levels,
mask,
)
ids = np.where(mask.astype("bool"))
for ci in ids:
parent_ids[ci] = gi
# Check if the grid structure is properly aligned (bug #1295)
for lvl in range(grid_levels.min() + 1, grid_levels.max() + 1):
idx = grid_levels.flatten() == lvl
dims = domain_dimensions * refine_by ** (lvl - 1)
for iax, ax in enumerate("xyz"):
cell_edges = np.linspace(
domain_left_edge[iax], domain_right_edge[iax], dims[iax], endpoint=False
)
if set(grid_left_edges[idx, iax]) - set(cell_edges):
raise YTIllDefinedAMR(lvl, ax)
if length_unit is None:
length_unit = "code_length"
if mass_unit is None:
mass_unit = "code_mass"
if time_unit is None:
time_unit = "code_time"
if velocity_unit is None:
velocity_unit = "code_velocity"
if magnetic_unit is None:
magnetic_unit = "code_magnetic"
particle_types = {}
for grid in sfh.values():
particle_types.update(set_particle_types(grid))
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
parent_ids,
number_of_particles,
np.zeros(ngrids).reshape((ngrids, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "AMRGridData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = refine_by
if np.all(domain_dimensions[1:] == 1):
dimensionality = 1
elif domain_dimensions[2] == 1:
dimensionality = 2
else:
dimensionality = 3
handler.dimensionality = dimensionality
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamDataset(handler, geometry=geometry, unit_system=unit_system)
return sds
def load_uniform_grid(
data,
domain_dimensions,
length_unit=None,
bbox=None,
nprocs=1,
sim_time=0.0,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(True, True, True),
geometry="cartesian",
unit_system="cgs",
):
r"""Load a uniform grid of data into yt as a
:class:`~yt.frontends.stream.data_structures.StreamHandler`.
This should allow a uniform grid of data to be loaded directly into yt and
analyzed as would any others. This comes with several caveats:
* Units will be incorrect unless the unit system is explicitly
specified.
* Some functions may behave oddly, and parallelism will be
disappointing or non-existent in most cases.
* Particles may be difficult to integrate.
Particle fields are detected as one-dimensional fields.
Parameters
----------
data : dict
This is a dict of numpy arrays or (numpy array, unit spec) tuples.
The keys are the field names.
domain_dimensions : array_like
This is the domain dimensions of the grid
length_unit : string
Unit to use for lengths. Defaults to unitless.
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units specified by length_unit.
Defaults to a cubic unit-length domain.
nprocs: integer, optional
If greater than 1, will create this number of subarrays out of data
sim_time : float, optional
The simulation time in seconds
mass_unit : string
Unit to use for masses. Defaults to unitless.
time_unit : string
Unit to use for times. Defaults to unitless.
velocity_unit : string
Unit to use for velocities. Defaults to unitless.
magnetic_unit : string
Unit to use for magnetic fields. Defaults to unitless.
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
geometry : string or tuple
"cartesian", "cylindrical", "polar", "spherical", "geographic" or
"spectral_cube". Optionally, a tuple can be provided to specify the
axis ordering -- for instance, to specify that the axis ordering should
be z, x, y, this would be: ("cartesian", ("z", "x", "y")). The same
can be done for other coordinates, for instance:
("spherical", ("theta", "phi", "r")).
Examples
--------
>>> np.random.seed(int(0x4D3D3D3))
>>> bbox = np.array([[0., 1.0], [-1.5, 1.5], [1.0, 2.5]])
>>> arr = np.random.random((128, 128, 128))
>>> data = dict(density=arr)
>>> ds = load_uniform_grid(data, arr.shape, length_unit='cm',
... bbox=bbox, nprocs=12)
>>> dd = ds.all_data()
>>> dd['density']
unyt_array([0.76017901, 0.96855994, 0.49205428, ..., 0.78798258,
0.97569432, 0.99453904], 'g/cm**3')
"""
from yt.frontends.stream.data_structures import (
StreamDataset,
StreamDictFieldHandler,
StreamHandler,
)
from yt.frontends.stream.definitions import (
assign_particle_data,
process_data,
set_particle_types,
)
domain_dimensions = np.array(domain_dimensions)
if bbox is None:
bbox = np.array([[0.0, 1.0], [0.0, 1.0], [0.0, 1.0]], "float64")
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros(nprocs, dtype="int32").reshape((nprocs, 1))
# If someone included this throw it away--old API
if "number_of_particles" in data:
issue_deprecation_warning(
"It is no longer necessary to include "
"the number of particles in the data "
"dict. The number of particles is "
"determined from the sizes of the "
"particle fields.",
since="4.0.0",
removal="4.1.0",
)
data.pop("number_of_particles")
# First we fix our field names, apply units to data
# and check for consistency of field shapes
field_units, data, number_of_particles = process_data(
data, grid_dims=tuple(domain_dimensions)
)
sfh = StreamDictFieldHandler()
if number_of_particles > 0:
particle_types = set_particle_types(data)
# Used much further below.
pdata = {"number_of_particles": number_of_particles}
for key in list(data.keys()):
if len(data[key].shape) == 1 or key[0] == "io":
if not isinstance(key, tuple):
field = ("io", key)
mylog.debug("Reassigning '%s' to '%s'", key, field)
else:
field = key
sfh._additional_fields += (field,)
pdata[field] = data.pop(key)
else:
particle_types = {}
if nprocs > 1:
temp = {}
new_data = {}
for key in data.keys():
psize = get_psize(np.array(data[key].shape), nprocs)
grid_left_edges, grid_right_edges, shapes, slices = decompose_array(
data[key].shape, psize, bbox
)
grid_dimensions = np.array([shape for shape in shapes], dtype="int32")
temp[key] = [data[key][slice] for slice in slices]
for gid in range(nprocs):
new_data[gid] = {}
for key in temp.keys():
new_data[gid].update({key: temp[key][gid]})
sfh.update(new_data)
del new_data, temp
else:
sfh.update({0: data})
grid_left_edges = domain_left_edge
grid_right_edges = domain_right_edge
grid_dimensions = domain_dimensions.reshape(nprocs, 3).astype("int32")
if length_unit is None:
length_unit = "code_length"
if mass_unit is None:
mass_unit = "code_mass"
if time_unit is None:
time_unit = "code_time"
if velocity_unit is None:
velocity_unit = "code_velocity"
if magnetic_unit is None:
magnetic_unit = "code_magnetic"
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
-np.ones(nprocs, dtype="int64"),
np.zeros(nprocs, dtype="int64").reshape(nprocs, 1), # particle count
np.zeros(nprocs).reshape((nprocs, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "UniformGridData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = 2
if np.all(domain_dimensions[1:] == 1):
dimensionality = 1
elif domain_dimensions[2] == 1:
dimensionality = 2
else:
dimensionality = 3
handler.dimensionality = dimensionality
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamDataset(handler, geometry=geometry, unit_system=unit_system)
# Now figure out where the particles go
if number_of_particles > 0:
# This will update the stream handler too
assign_particle_data(sds, pdata, bbox)
return sds
def load_unstructured_mesh(
connectivity,
coordinates,
node_data=None,
elem_data=None,
length_unit=None,
bbox=None,
sim_time=0.0,
mass_unit=None,
time_unit=None,
velocity_unit=None,
magnetic_unit=None,
periodicity=(False, False, False),
geometry="cartesian",
unit_system="cgs",
):
r"""Load an unstructured mesh of data into yt as a
:class:`~yt.frontends.stream.data_structures.StreamHandler`.
This should allow an unstructured mesh data to be loaded directly into
yt and analyzed as would any others. Not all functionality for
visualization will be present, and some analysis functions may not yet have
been implemented.
Particle fields are detected as one-dimensional fields. The number of
particles is set by the "number_of_particles" key in data.
In the parameter descriptions below, a "vertex" is a 3D point in space, an
"element" is a single polyhedron whose location is defined by a set of
vertices, and a "mesh" is a set of polyhedral elements, each with the same
number of vertices.
Parameters
----------
connectivity : list of array_like or array_like
This should either be a single 2D array or list of 2D arrays. If this
is a list, each element in the list corresponds to the connectivity
information for a distinct mesh. Each array can have different
connectivity length and should be of shape (N,M) where N is the number
of elements and M is the number of vertices per element.
coordinates : array_like
The 3D coordinates of mesh vertices. This should be of size (L, D) where
L is the number of vertices and D is the number of coordinates per vertex
(the spatial dimensions of the dataset). Currently this must be either 2 or 3.
When loading more than one mesh, the data for each mesh should be concatenated
into a single coordinates array.
node_data : dict or list of dicts
For a single mesh, a dict mapping field names to 2D numpy arrays,
representing data defined at element vertices. For multiple meshes,
this must be a list of dicts. Note that these are not the values as a
function of the coordinates, but of the connectivity. Their shape
should be the same as the connectivity. This means that if the data is
in the shape of the coordinates, you may need to reshape them using the
`connectivity` array as an index.
elem_data : dict or list of dicts
For a single mesh, a dict mapping field names to 1D numpy arrays, where
each array has a length equal to the number of elements. The data
must be defined at the center of each mesh element and there must be
only one data value for each element. For multiple meshes, this must be
a list of dicts, with one dict for each mesh.
bbox : array_like (xdim:zdim, LE:RE), optional
Size of computational domain in units of the length unit.
sim_time : float, optional
The simulation time in seconds
mass_unit : string
Unit to use for masses. Defaults to unitless.
time_unit : string
Unit to use for times. Defaults to unitless.
velocity_unit : string
Unit to use for velocities. Defaults to unitless.
magnetic_unit : string
Unit to use for magnetic fields. Defaults to unitless.
periodicity : tuple of booleans
Determines whether the data will be treated as periodic along
each axis
geometry : string or tuple
"cartesian", "cylindrical", "polar", "spherical", "geographic" or
"spectral_cube". Optionally, a tuple can be provided to specify the
axis ordering -- for instance, to specify that the axis ordering should
be z, x, y, this would be: ("cartesian", ("z", "x", "y")). The same
can be done for other coordinates, for instance:
("spherical", ("theta", "phi", "r")).
Examples
--------
Load a simple mesh consisting of two tets.
>>> # Coordinates for vertices of two tetrahedra
>>> coordinates = np.array([[0.0, 0.0, 0.5], [0.0, 1.0, 0.5],
... [0.5, 1, 0.5], [0.5, 0.5, 0.0],
... [0.5, 0.5, 1.0]])
>>> # The indices in the coordinates array of mesh vertices.
>>> # This mesh has two elements.
>>> connectivity = np.array([[0, 1, 2, 4], [0, 1, 2, 3]])
>>>
>>> # Field data defined at the centers of the two mesh elements.
>>> elem_data = {
... ('connect1', 'elem_field'): np.array([1, 2])
... }
>>>
>>> # Field data defined at node vertices
>>> node_data = {
... ('connect1', 'node_field'): np.array([[0.0, 1.0, 2.0, 4.0],
... [0.0, 1.0, 2.0, 3.0]])
... }
>>>
>>> ds = load_unstructured_mesh(connectivity, coordinates,
... elem_data=elem_data,
... node_data=node_data)
"""
from yt.frontends.exodus_ii.util import get_num_pseudo_dims
from yt.frontends.stream.data_structures import (
StreamDictFieldHandler,
StreamHandler,
StreamUnstructuredMeshDataset,
)
from yt.frontends.stream.definitions import process_data, set_particle_types
dimensionality = coordinates.shape[1]
domain_dimensions = np.ones(3, "int32") * 2
nprocs = 1
if elem_data is None and node_data is None:
raise RuntimeError("No data supplied in load_unstructured_mesh.")
connectivity = list(always_iterable(connectivity, base_type=np.ndarray))
num_meshes = max(1, len(connectivity))
elem_data = list(always_iterable(elem_data, base_type=dict)) or [{}] * num_meshes
node_data = list(always_iterable(node_data, base_type=dict)) or [{}] * num_meshes
data = [{} for i in range(num_meshes)]
for elem_dict, data_dict in zip(elem_data, data):
for field, values in elem_dict.items():
data_dict[field] = values
for node_dict, data_dict in zip(node_data, data):
for field, values in node_dict.items():
data_dict[field] = values
if bbox is None:
bbox = [
[
coordinates[:, i].min() - 0.1 * abs(coordinates[:, i].min()),
coordinates[:, i].max() + 0.1 * abs(coordinates[:, i].max()),
]
for i in range(dimensionality)
]
if dimensionality < 3:
bbox.append([0.0, 1.0])
if dimensionality < 2:
bbox.append([0.0, 1.0])
# handle pseudo-dims here
num_pseudo_dims = get_num_pseudo_dims(coordinates)
dimensionality -= num_pseudo_dims
for i in range(dimensionality, 3):
bbox[i][0] = 0.0
bbox[i][1] = 1.0
bbox = np.array(bbox, dtype=np.float64)
domain_left_edge = np.array(bbox[:, 0], "float64")
domain_right_edge = np.array(bbox[:, 1], "float64")
grid_levels = np.zeros(nprocs, dtype="int32").reshape((nprocs, 1))
field_units = {}
particle_types = {}
sfh = StreamDictFieldHandler()
sfh.update({"connectivity": connectivity, "coordinates": coordinates})
for i, d in enumerate(data):
_f_unit, _data, _ = process_data(d)
field_units.update(_f_unit)
sfh[i] = _data
particle_types.update(set_particle_types(d))
grid_left_edges = domain_left_edge
grid_right_edges = domain_right_edge
grid_dimensions = domain_dimensions.reshape(nprocs, 3).astype("int32")
if length_unit is None:
length_unit = "code_length"
if mass_unit is None:
mass_unit = "code_mass"
if time_unit is None:
time_unit = "code_time"
if velocity_unit is None:
velocity_unit = "code_velocity"
if magnetic_unit is None:
magnetic_unit = "code_magnetic"
# I'm not sure we need any of this.
handler = StreamHandler(
grid_left_edges,
grid_right_edges,
grid_dimensions,
grid_levels,
-np.ones(nprocs, dtype="int64"),
np.zeros(nprocs, dtype="int64").reshape(nprocs, 1), # Temporary
np.zeros(nprocs).reshape((nprocs, 1)),
sfh,
field_units,
(length_unit, mass_unit, time_unit, velocity_unit, magnetic_unit),
particle_types=particle_types,
periodicity=periodicity,
)
handler.name = "UnstructuredMeshData"
handler.domain_left_edge = domain_left_edge
handler.domain_right_edge = domain_right_edge
handler.refine_by = 2
handler.dimensionality = dimensionality
handler.domain_dimensions = domain_dimensions
handler.simulation_time = sim_time
handler.cosmology_simulation = 0
sds = StreamUnstructuredMeshDataset(
handler, geometry=geometry, unit_system=unit_system
)
fluid_types = ["all"]
for i in range(1, num_meshes + 1):
fluid_types += ["connect%d" % i]
sds.fluid_types = tuple(fluid_types)
def flatten(l):
return [item for sublist in l for item in sublist]
sds._node_fields = flatten([[f[1] for f in m] for m in node_data if m])
sds._elem_fields = flatten([[f[1] for f in m] for m in elem_data if m])
sds.default_field = [f for f in sds.field_list if f[0] == "connect1"][-1]
return sds