Combinatorics¶

Functionality¶

Combinatorics node performs various combinatoric operations like: Product, Permutations and Combinations.

Inputs¶

The inputs to the node are a set of lists of any type and a set of control parameters.

The list inputs in combination to the control parameter inputs (Repeat / Length) are vectorized and the control parameters accept either single or multiple values for vectorization.

List inputs to the node: - A - B [1] … - Z [1]

Notes: [1] : The multiple list inputs are available for the Product operation, all the other operations take one list input. For the Product operation as the last list input is connected a new empty input socket will appear to allow other lists to be connected.

Parameters¶

The Operation parameter allows to select one of following operations: Product, Permutations and Combinations.

All parameters except Operation can be given as an external input.

Param	Type	Default	Description
Operation	Enum: Product Permutations Combinations	Product	See details in the Operations section.
Repeat	Int	1	Repeat the input lists this many times [1]
Length	Int	1	The number of the elements in the list to operate on [2]
A	List		The list of elements to operate on.
B..Z	List		Additional lists to operate on [3]

Notes: [1] : The Repeat parameter is only available for the Product operation. [2] : The Length parameter is only available for the Permutations and Combinations operation. [3] : Additional lists inputs are available only for the Product operation.

Operations¶

Product

For this operation the node allows an arbitrary number of input lists to be product together as: A x B x .. x Z. The result of the product operation is a list of elements each of size equal to the number of input lists and has all the combinations of elements from the first list, followed by all elements in the second list etc.

e.g. for two connected list inputs:

A : [“X”, “Y”] B : [1, 2, 3]

The result A x B is:

[“X”, “Y”] x [1, 2, 3] => [ [“X”, 1], [“X”, 2], [“X”, 3], [“Y”, 1], [“Y”, 2], [“Y”, 3] ]

The value of the Repeat parameter makes the node compute the product of all the connected lists replicated this number of times.

e.g. for one connected input with repeat value of 2:

A : [“X”, “Y”] Repeat: 2

The result A x A is:

[“X”, “Y”] x [“X”, “Y”] => [ [“X”, “X”], [“X”, “Y”], [“Y”, “X”], [“Y”, “Y”] ]

Permutations

For this operation the node take a single input list and generates the permutations of its elements. The Length parameter sets the number of elements in the list to be permutated.

Notes: * If the Length is zero, the node will permute ALL elements in the list. * The Length value is bounded between zero and the length of the input list, so any length values larger than the length of the input list is equivalent to permuting ALL elements in the list.

e.g. for a list of 3 (mixed) elements:

A: [“X”, 3, (1,1,1)] L: 3

The result is:

[
  ['X', 3, (1, 1, 1)],
  ['X', (1, 1, 1), 3],
  [3, 'X', (1, 1, 1)],
  [3, (1, 1, 1), 'X'],
  [(1, 1, 1), 'X', 3],
  [(1, 1, 1), 3, 'X']
]

Combinations

For this operation the node takes a single list as input and generates the combinations of its elements taking L number of elements given by the Length parameter.

Notes: * If the Length is zero, the node will combine ALL elements in the list. * The Length value is bounded between zero and the length of the input list, so any length values larger than the length of the input list is equivalent to combining ALL elements.

e.g. for a list of 4 elements taken 2 elements:

A : [1, ‘X’, (1, 2, 3), [1, 3]] L : 2

The result is:

[
  [1, 'X'],
  [1, (1, 2, 3)],
  [1, [1, 3]],
  ['X', (1, 2, 3)],
  ['X', [1, 3]],
  [(1, 2, 3), [1, 3]]
]

Outputs¶

Result The list of product, permutations or combinations.

The results will be generated only when the Result output is connected.