NDCollection

class ndcube.NDCollection(key_data_pairs, aligned_axes=None, meta=None, **kwargs)[source] [edit on github]

Bases: dict

A class for holding and manipulating a collection of aligned NDCube or NDCubeSequences.

Parameters
  • data (sequence of tuple`s of (`str, NDCube or NDCubeSequence)) – The names and data cubes/sequences to held in the collection.

  • aligned_axes (tuple of int, tuple of tuple`s of `int, ‘all’, or None, optional) – Axes of each cube/sequence that are aligned in numpy order. If elements are int, then the same axis numbers in all cubes/sequences are aligned. If elements are tuples of ints, then must be one tuple for every cube/sequence. Each element of each tuple gives the axes of each cube/sequence that are aligned. If ‘all’, all axes are aligned in natural order, i.e. the 0th axes of all cubes are aligned, as are the 1st, and so on. Default=None

  • meta (dict, optional) – General metadata for the overall collection.

Example

Say the collection holds two NDCubes, each of 3 dimensions. aligned_axes = (1, 2) means that axis 1 (0-based counting) of cube0 is aligned with axis 1 of cube1, and axis 2 of cube0 is aligned with axis 2 of cube1. However, if aligned_axes = ((0, 1), (2, 1)) then the first tuple corresponds to cube0 and the second with cube1. This is interpretted as axis 0 of cube0 is aligned with axis 2 of cube1 while axis 1 of cube0 is aligned with axis 1 of cube1.

Attributes Summary

aligned_dimensions

Returns the lengths of all aligned axes.

aligned_world_axis_physical_types

Returns the physical types of the aligned axes of an ND object in the collection.

Methods Summary

copy()

pop(k[,d])

If key is not found, d is returned if given, otherwise KeyError is raised

popitem()

2-tuple; but raise KeyError if D is empty.

setdefault()

Insert key with a value of default if key is not in the dictionary.

update(*args)

Merges a new collection with current one replacing objects with common keys.

Attributes Documentation

aligned_dimensions

Returns the lengths of all aligned axes.

If there are no aligned axes, returns None.

aligned_world_axis_physical_types

Returns the physical types of the aligned axes of an ND object in the collection.

If there are no aligned axes, returns None.

Methods Documentation

copy() → a shallow copy of D[source] [edit on github]
pop(k[, d]) → v, remove specified key and return the corresponding value.[source] [edit on github]

If key is not found, d is returned if given, otherwise KeyError is raised

popitem() → (k, v), remove and return some (key, value) pair as a[source] [edit on github]

2-tuple; but raise KeyError if D is empty.

setdefault()[source] [edit on github]

Insert key with a value of default if key is not in the dictionary.

Return the value for key if key is in the dictionary, else default.

update(*args)[source] [edit on github]

Merges a new collection with current one replacing objects with common keys.

Takes either a single input (NDCollection) or two inputs (sequence of key/value pair and aligned axes associated with each key/value pair.