Set Data Structure

Description

This is a javascript implementation of a set data structure.

A set data structure is an implementation of the mathematical concept of a finite set. A set is a collection of unique values (no duplicates) that have no particular order. A set is more concerned whether or not values are contained in the set than the order in which they are added.

This implementation of a set inlcudes the common set operations of union, intersection, difference, and subset.

For specific examples and documentation, see the below sections

Basic Usage

Install with npm :

npm install set-ds --save

Basic usage example below. Note: it does not cover all the available methods, rather just highlights the main functionality to get up and running with this data structure. For a description of all the methods, see the API section.

var SetDS = require('set-ds');
var setA = new SetDS();

setA.isEmpty();
// --> true
setA.add(1);
setA.add(2);
setA.add(3);
setA.add(4);
setA.add(5);

setA.values();
// --> [1, 2, 3, 4, 5]

setA.has(4);
// --> true

// or instantiate with an array or args
var setB = new SetDS([7, 6, 5, 8, 4]);
setB.isEmpty();
// --> false

setB.values();
// --> [4, 5, 6, 7, 8]

var setC = setA.union(setB);
setC.values();
// --> [1, 2, 3, 4, 5, 6, 7, 8]

var setD = setA.intersection(setB);
setD.values();
// --> [4, 5]

var setE = setA.difference(setB);
setE.values();
// --> [1, 2, 3]

setA.subset(new SetDS(1, 7, 3, 4, 6, 5, 2));
// --> true

setA.clear();
setA.isEmpty();
// --> true

API

Available methods for a Set instance:

• isEmpty()

  Determines if the set is empty

• size()

  Returns the size, or number of items in the set

• clear()

  Clears all the items from the set

• add(value)

  Adds an item to the set. If the set already contains the item, it is not added.

• remove(value)

  Removes an item from the set.

• has(value)

  Determines of the set contains, or has, the value

• values()

  Returns an array containing all the items in the set

• union(otherSet)

  Returns a Set that is the union of this set and the 'otherSet'. The returned set will contain all the elements from both sets, and by definition, will not contain any duplicates.

• intersection(otherSet)

  Returns a Set that ts the intersection of this set and the 'otherSet', The returned set will have only those items that both sets have in common.

• difference(otherSet)

  Returns a Set that ts the different of this and the 'otherSet', The returned set will have those items that are contained in this set, but NOT contained in the 'otherSet'.

• subset(otherSet)

  Returns whether or not this set is a subset of the 'otherSet'. If all items of this set are contained in the otherSet, this function returns true; false otherwise.

License

MIT © Jason Jones