astrodendro.structure.Structure¶

class
astrodendro.structure.
Structure
(indices, values, children=[], idx=None, dendrogram=None)¶ A structure in the dendrogram, for example a leaf or a branch.
A structure that is part of a dendrogram knows which other structures it is related to. For example, it is possible to get the parent structure containing the present structure
s
by using theparent
attribute:>>> s.parent <Structure type=branch idx=2152>
Likewise, the
children
attribute can be used to get a list of all substructures:>>> s.children [<Structure type=branch idx=1680>, <Structure type=branch idx=5771>]
A number of attributes and methods are available to explore the structure in more detail, such as the
indices
andvalues
methods, which return the indices and values of the pixels that are part of the structure. These and other methods have asubtree=
option, which ifTrue
(the default) returns the quantities related to structure and all substructures, and ifFalse
includes only the pixels that are part of the structure, but excluding any substructure.Attributes
is_leaf
Whether the present structure is a leaf. is_branch
Whether the present structure is a branch. vmin
The minimum value of pixels belonging to the branch (excluding substructure). vmax
The maximum value of pixels belonging to the branch (excluding substructure). height
This is defined as the minimum value in the children structures, or the peak value of the present structure if it has no children. ancestor
Find the ancestor of this leaf/branch nonrecursively. parent
The parent structure containing the present structure. children
A list of all the substructures contained in the present structure. descendants
Get a flattened list of all child leaves and branches. level
The level of the structure, i.e. newick
Methods
indices
([subtree])The indices of the pixels in this branch. values
([subtree])The values of the pixels in this branch. get_npix
([subtree])Return the number of pixels in this structure. get_peak
([subtree])Return (index, value) for the pixel with maximum value. sorted_leaves
([sort_key, reverse, subtree])Return a list of sorted leaves. get_mask
([shape, subtree])Return a boolean mask outlining the structure. Methods (detail)

indices
(subtree=True)¶ The indices of the pixels in this branch.
Parameters: subtree : bool, optional
Whether to recursively include all substructures

values
(subtree=True)¶ The values of the pixels in this branch.
Parameters: subtree : bool, optional
Whether to recursively include all substructures

get_npix
(subtree=True)¶ Return the number of pixels in this structure.
Parameters: subtree : bool, optional
Whether to recursively include all substructures when counting the pixels.
Returns: n_pix : int
The number of pixels in this structure

get_peak
(subtree=True)¶ Return (index, value) for the pixel with maximum value.
Parameters: subtree : bool, optional
Whether to recursively include all substructures when searching for the peak.
Returns: index : tuple
The ndimensional index of the peak pixel
value : float
The value of the peak pixel

sorted_leaves
(sort_key=<function <lambda>>, reverse=False, subtree=True)¶ Return a list of sorted leaves.
Parameters: sort_key : function, optional
A function which given a structure will return a scalar that is then used for sorting. By default, this is set to a function that returns the peak value of a structure (including descendants).
reverse : bool, optional
Whether to reverse the sorting.
subtree : bool, optional
Whether to recursively include all substructures in the list.
Returns: leaves : list
A list of sorted leaves

get_mask
(shape=None, subtree=True)¶ Return a boolean mask outlining the structure.
Parameters: shape : tuple, optional
The shape of the array upon which to compute the mask. This is only required if the structure is not attached to a dendrogram.
subtree : bool, optional
Whether to recursively include all substructures in the mask.
Returns: mask :
ndarray
The mask outlining the structure (
False
values are used outside the structure, andTrue
values inside).
