Classes
LinearMesh (Plin, BoxSize, Nmesh[, seed, …]) 
A MeshSource object that generates a RealField density mesh from a linear power spectrum function \(P(k)\). 
nbodykit.source.mesh.linear.
LinearMesh
(Plin, BoxSize, Nmesh, seed=None, unitary_amplitude=False, inverted_phase=False, remove_variance=None, comm=None)[source]¶A MeshSource object that generates a RealField
density
mesh from a linear power spectrum function \(P(k)\).
Parameters: 


Attributes: 
Methods
apply (func[, kind, mode]) 
Return a view of the mesh, with actions updated to apply the specified function, either in Fourier space or configuration space, based on mode 
compute ([mode, Nmesh]) 
Compute / Fetch the mesh object into memory as a RealField or ComplexField object. 
preview ([axes, Nmesh, root]) 
Gather the mesh into as a numpy array, with (reduced) resolution. 
save (output[, dataset, mode]) 
Save the mesh as a BigFileMesh on disk, either in real or complex space. 
to_complex_field () 
Return a ComplexField, generating from the linear power spectrum. 
to_field ([mode, out]) 
Return the mesh as a pmesh Field object, either in Fourier space or configuration space, based on mode . 
to_real_field ([out, normalize]) 
Convert the mesh source to the configurationspace field, returning a pmesh.pm.RealField object. 
view () 
Return a “view” of the MeshSource, in the spirit of numpy’s ndarray view. 
paint 
__finalize__
(other)¶Finalize the creation of a MeshSource object by copying over attributes from a second MeshSource.
Parameters:  other (MeshSource) – the second MeshSource to copy over attributes from 

__len__
()¶Length of a mesh source is zero
actions
¶A list of actions to apply to the density field when interpolating to the mesh.
This stores tuples of (mode, func, kind)
; see apply()
for more details.
apply
(func, kind='wavenumber', mode='complex')¶Return a view of the mesh, with actions
updated to
apply the specified function, either in Fourier space or
configuration space, based on mode
Parameters: 


Returns:  a view of the mesh object with the 
Return type: 
attrs
¶A dictionary storing relevant metadata about the CatalogSource.
compute
(mode='real', Nmesh=None)¶Compute / Fetch the mesh object into memory as a RealField or ComplexField object.
preview
(axes=None, Nmesh=None, root=0)¶Gather the mesh into as a numpy array, with (reduced) resolution. The result is broadcast to all ranks, so this uses \(\mathrm{Nmesh}^3\) per rank.
Parameters:  

Returns:  out – An numpy array holding the real density field. 
Return type:  array_like 
save
(output, dataset='Field', mode='real')¶Save the mesh as a BigFileMesh
on disk, either in real or complex space.
Parameters: 

to_complex_field
()[source]¶Return a ComplexField, generating from the linear power spectrum.
Note
The density field is normalized to \(1+\delta\) such that the mean of the return field in real space is unity.
Returns:  an arraylike object holding the generated linear density field in Fourier space 

Return type:  pmesh.pm.ComplexField 
to_field
(mode='real', out=None)¶Return the mesh as a pmesh
Field object, either in Fourier
space or configuration space, based on mode
.
This will call to_real_field()
or to_complex_field()
based on mode
.
Parameters:  mode ('real' or 'complex') – the return type of the field 

Returns:  either a RealField of ComplexField, storing the value of the field on the mesh 
Return type:  RealField , ComplexField 
to_real_field
(out=None, normalize=True)¶Convert the mesh source to the configurationspace field,
returning a pmesh.pm.RealField
object.
Not implemented in the base class, unless object is a view.
view
()¶Return a “view” of the MeshSource, in the spirit of numpy’s ndarray view.
This returns a new MeshSource whose memory is owned by self
.
Note that for CatalogMesh objects, this is overidden by the
CatalogSource.view
function.