linear-array

linear-array

Javascript / Node.js utility library. Returns a set of utility functions, available through the lineArr namespace, which serve to generate arrays populated with sequences such as natural or stepWithOffset sequence, and to check if an array is a sequence of a certain type (like a natural sequence [0,1,2,3,4]).

Install

There are 2 ways to install and use the library.

• npm

$ npm install --save linear-array

• import with a <script> tag

<script
  type="module"
  src="https://unpkg.com/linear-array@2.0.0/linear-array.js"
></script>

Importing in project

Since this package can be used on the client side, as UMD or ES6 module, and server side, as CommonJS module, there are 2 ways to import it into your .js file:

• CommonJS

const lineArr = require('linear-array');

• ES6

import lineArr from 'linear-array';

• UMD

Use the globally available lineArr module directly in your code.

It is being imported from the linear-array liibrary with the <script> tag, and is attached to the globally available window variable.

Usage

Currently, there are 4 methods available through the lineArr module / namespace.

Based on the differences in their input and output data types, they can be divided into 2 categories;

• inputs / arguments are finite integers, the output value is a filled array of finite integers sorted in an increasing order according to a specific pattern
• input / argument is an array of finite integers, and the output value is a boolean which indicates it the given array conforms to a specific pattern

But both categories operate on the same pattern of data types, and these patterns can be categorized in a mathematical sense as Sequences.

But, repetition of numbers in the arrays is not allowed.

Sequence of natural numbers

fillSeqNaturalNumbers (limiter: number, [includeLast = false]: boolean) => number[]

fillSeqNaturalNumbers(limiter, inludeLast?) === [0, 1, 2, 3, ... , includeLast ? limiter : (limiter - 1)]

(0) -> []

(7) -> [0, 1, 2, 3, 4, 5, 6]

(7, true) -> [0, 1, 2, 3, 4, 5, 6, 7]

isSeqNaturalNumbers(arr: number[]) => boolean

isSeqNaturalNumbers(arr) === true || false

([]) -> false

([0]) -> true

([0,1,2,3,4]) -> true

([2,3,4,5,6]) -> false

([0,1,2,3,5]) -> false

Sequence of numbers with a specified fixed step and offset

fillStepSequenceWithOffset (limiter: number, [step = 1]: number, [offset = 0]: number) => number[]

fillStepSequenceWithOffset(limiter, step?, offset?) === [0+offset, step + offset, 2*step + offset, ..., (limiter - 1)*step + offset]

(0) -> []

(0,1,1) -> []

(1,1,1) -> [1]

(5) -> [0, 1, 2, 3, 4]

(5,1,3) -> [3, 4, 5, 6, 7]

(5,3) -> [0, 3, 6, 9, 12]

(5,2,2) -> [2, 4, 6, 8, 10]

isStepSequenceWithOffset (arr: number[], [step = 1]: number, [offset = 0]: number) => boolean

isStepSequenceWithOffset(arr, step?, offset?) === true || false

([]) -> false

([0]) -> true

([0],1,1) -> false

([0,1,2,3,4]) -> true

([0,1,2,3,4], 2) -> false

([0,1,2,3,4], 1, 1) -> false

([1,2,3,4,5], 1, 1) -> true

([6,9,12,15,18], 3, 6) -> true

([5,9,12,15,19], 3, 6) -> false

Release history

2.0.0.

BREAKING CHANGES:

The linearArray method no longer exists and it is not imported directly from the library.

Instead, a module called lineArr is imported and it contains a set of methods. See the Usage section on what they are and how they are used.

The closes equivalent to the old linearArray method is now fillSeqNaturalNumbers

NEW FEATURES:

This update has 4 new methods which can be accessed through the lineArr module.

• lineArr.fillSeqNaturalNumbers

• lineArr.isSeqNaturalNumbers

• lineArr.fillStepSequenceWithOffset

• lineArr.isStepSequenceWithOffset

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Contributors ✨

Many thanks goes to these people for helping me maintain and upgrade the project:

Amin NAIRI 💻 🤔 ⚠️

Author

Ivan Spoljaric

• LinkedIn

License

Copyright © 2020, Ivan Spoljaric. Released under the MIT License.