Classes
MultipleSpeciesCatalogMesh (*args, **kwargs) |
A subclass of CatalogMesh designed to paint the density field from a sum of multiple types of particles. |
nbodykit.source.catalogmesh.species.
MultipleSpeciesCatalogMesh
(*args, **kwargs)[source]¶A subclass of CatalogMesh
designed to paint the density field from a sum of multiple types
of particles.
The paint()
function paints the density field summed over
all particle species.
Parameters: |
|
---|
Attributes
Index |
The attribute giving the global index rank of each particle in the list. |
actions |
The actions to apply to the interpolated density field, optionally included the compensation correction. |
attrs |
A dictionary storing relevant meta-data about the CatalogSource. |
columns |
All columns in the CatalogSource, including those hard-coded into the class’s defintion and override columns provided by the user. |
compensated |
Boolean flag to indicate whether to correct for the windowing kernel introduced when interpolating the discrete particles to a continuous field. |
csize |
The total, collective size of the CatalogSource, i.e., summed across all ranks. |
hardcolumns |
A list of the hard-coded columns in the CatalogSource. |
interlaced |
Whether to use interlacing when interpolating the density field. |
size |
The number of objects in the CatalogSource on the local rank. |
use_cache |
If set to True , use the built-in caching features of dask to cache data in memory. |
window |
String specifying the name of the interpolation kernel when gridding the density field. |
Methods
CompensateCIC (w, v) |
Return the Fourier-space kernel that accounts for the convolution of |
CompensateCICAliasing (w, v) |
Return the Fourier-space kernel that accounts for the convolution of |
CompensateTSC (w, v) |
Return the Fourier-space kernel that accounts for the convolution of the gridded field with the TSC window function in configuration space. |
CompensateTSCAliasing (w, v) |
Return the Fourier-space kernel that accounts for the convolution of |
Selection () |
A boolean column that selects a subset slice of the CatalogSource. |
Value () |
When interpolating a CatalogSource on to a mesh, the value of this array is used as the Value that each particle contributes to a given mesh cell. |
Weight () |
The column giving the weight to use for each particle on the mesh. |
apply (func[, kind, mode]) |
Return a view of the mesh, with actions updated to |
compute (*args, **kwargs) |
Our version of dask.compute() that computes multiple delayed dask collections at once. |
copy () |
Return a shallow copy of self . |
get_hardcolumn (col) |
Construct and return a hard-coded column. |
gslice (start, stop[, end, redistribute]) |
Execute a global slice of a CatalogMesh. |
make_column (array) |
Utility function to convert an array-like object to a dask.array.Array . |
paint ([mode, Nmesh]) |
Paint the density on the mesh and apply any transformation functions specified in actions . |
preview ([axes, Nmesh, root]) |
Gather the mesh into as a numpy array, with (reduced) resolution. |
read (columns) |
Return the requested columns as dask arrays. |
save (output[, dataset, mode]) |
Save the mesh as a BigFileMesh on disk, either in real or complex space. |
sort (keys[, reverse, usecols]) |
Sort the CatalogMesh object globally across all MPI ranks in ascending order by the input keys. |
to_complex_field ([out]) |
Convert the mesh source to the Fourier-space field, returning a pmesh.pm.ComplexField object. |
to_field ([mode, out]) |
Return the mesh as a pmesh Field object, either in Fourier space or configuration space, based on mode . |
to_mesh ([Nmesh, BoxSize, dtype, interlaced, …]) |
Convert the CatalogSource to a MeshSource, using the specified parameters. |
to_real_field ([normalize]) |
Paint the density field holding the sum of all particle species, returning a RealField object. |
view ([type]) |
Return a “view” of the CatalogSource object, with the returned type set by type . |
__getitem__
(key)[source]¶If indexed by a species name, return a CatalogMesh object holding only the data columns for that species with the same parameters as the current object.
If not a species name, this has the same behavior as
CatalogSource.__getitem__()
.
to_real_field
(normalize=True)[source]¶Paint the density field holding the sum of all particle species,
returning a RealField
object.
Meta-data computed for each particle is stored in the attrs
attribute of the returned RealField, with keys that are prefixed by
the species name. In particular, the total shot noise for the
mesh is defined as:
where the sum is over all species in the catalog, W_i
is the
sum of the Weight
column for the \(i^\mathrm{th}\) species,
and \(W_\mathrm{tot}\) is the sum of \(W_i\) across all species.
Parameters: | normalize (bool, optional) – if True , normalize the density field as \(1+\delta\),
dividing by the total mean number of objects per cell, as given
by the num_per_cell meta-data value in attrs |
---|---|
Returns: | the RealField holding the painted density field, with a
attrs dictionary attribute holding the meta-data |
Return type: | RealField |