chunky

v0.1.0

chunky v0.1.0 Chunky View Source

Extended chunking and enumeration manipulations.

Functions

  • Chunky.permutations/1 - Generate all combinations of a set of values, with no duplication
  • Chunky.filter_with_predicates/2 - Filter an enumeration to only those entries that meet all the provided predicate functions
  • Chunky.chunk_runs/1 - Chunk an enumerable by runs of duplicate values
  • Chunky.chunk_to_length/2 - Chunk an enumerable into specific length chunks

TODO: Chunky.filter_with_predicates/2 TODO: Chunky.take_sequences/1 TODO: Chunky.take_chunks/2

Link to this section Summary

Functions

permutations(list)

Generate all of the permutations, without duplicates, from a set of values. The set of values can be

Link to this section Functions

Link to this function

permutations(list)

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Generate all of the permutations, without duplicates, from a set of values. The set of values can be:

  • a list of any type, like [1, 2, 3] or [:a, :b, %{}]
  • a string or binary, like "abcd"
  • a tuple, like {1, :b, "asdf"}
  • a range, like 1..4 or 3..-1

This is not lazy generated, so a permutation of a large set may take awhile. Keep in mind that the total number of permutations for a set of N values is N!.

When a set is permuted, the resulting list will contain values in the shape of the original; a permuted list will contains lists, permuted tuples will contain tuples, permuted strings will contain strings. The only exception is ranges, which will result in lists.

So, for instance, a permuted string will result in a list of strings. Chunky should handle Unicode just fine:

iex> Chunky.permutations("😀★⍵")
["😀★⍵", "😀⍵★", "★😀⍵", "★⍵😀", "⍵😀★", "⍵★😀"]

Examples 

iex> Chunky.permutations([1, 2, 3])
[[1, 2, 3], [1, 3, 2], [2, 1, 3], [2, 3, 1], [3, 1, 2], [3, 2, 1]]

iex> Chunky.permutations("abc")
["abc", "acb", "bac", "bca", "cab", "cba"]

iex> Chunky.permutations({:a, :b, :c})
[ {:a, :b, :c}, {:a, :c, :b}, {:b, :a, :c}, {:b, :c, :a}, {:c, :a, :b}, {:c, :b, :a} ]

iex> Chunky.permutations(1..-1)
[ [1, 0, -1], [1, -1, 0], [0, 1, -1], [0, -1, 1], [-1, 1, 0], [-1, 0, 1]]