IterFun

About

IterFun implements an eager iterator class reminiscent of Elixir's Enum structure that features a series of handy methods for performing common data transformations.

It's a continuously evolving project specifically developed to meet my personal needs, but I have decided to put it out in the open in case someone else find it as useful as me. Contributions in form of pull requests or suggestions are always welcome. If you need a more mature library for your project, consider one of these alternatives instead:

• toolz
• fn.py
• more-itertools
• Pipe

Examples

Two Sum Problem

Given an array of integers domain and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same element twice. You can return the answer in any order.

from iterfun import Iter

target = 12
domain = [45, 26, 5, 41, 58, 97, 82, 9, 79, 22, 3, 74, 70, 84, 17, 79, 41, 96, 13, 89]

pair = Iter(domain) \
    .filter(lambda x: x < target) \
    .combinations(2) \
    .filter(lambda x: sum(x) == target) \
    .flatten() \
    .to_list()

# [7, 10]
print(Iter(domain).find_index(lambda x: x in pair).image)

Technical Limitations

For reasons of simplicity, the mutable state in image is exposed as a list or dictionary and not as a generator which is capable of dealing with very large sequences. It's an implementation detail that is necessary for some index-based methods, though this behavior might change in future versions of this library where applicable.

There is probably room to improve the overall performance and accuracy of this library. To this end, future updates will also increase the test coverage in order to consider more edge cases and method interoperability. Notice that the terms and conditions of the MIT License will always apply.

Method Reference

This method reference serves as a first point of contact to help you discover what this library is capable of. Documentation and small, self-contained examples are provided in the doc strings of each method that you can read in the privacy of your code editor of choice.

Functions

• invert
• is_even
• is_odd
• is_prime
• miller_rabin
• sign

Iter

• all
• any
• at
• avg
• cartesian
• chunk_by
• chunk_every
• chunk_while
• combinations
• combinations_with_replacement
• count
• count_until
• dedup
• dedup_by
• difference
• drop
• drop_every
• drop_while
• duplicates
• filter
• find
• find_index
• find_value
• flat_map
• flat_map
• flat_map_reduce
• flatten
• frequencies
• group_by
• intersects
• intersperse
• into
• is_disjoint
• is_empty
• is_member
• is_subset
• is_superset
• join
• linspace
• map
• map_every
• map_intersperse
• map_join
• map_reduce
• max
• min
• min_max
• open
• permutations
• product
• randint
• random
• range
• reduce
• reduce_while
• reject
• reverse
• reverse_slice
• save
• scan
• shorten
• shuffle
• slice
• slide
• sort
• split
• split_while
• split_with
• sum
• symmetric_difference
• take
• take_every
• take_random
• take_while
• to_dict
• to_list
• transpose
• union
• unique
• unzip
• with_index
• zip_reduce
• zip_with

Authors

See also the list of contributors who participated in this project.

License

This project is licensed under the MIT License - see the LICENSE file for more details.