ixfx
    Preparing search index...

    Class NumberMap<K>

    Simple map for numbers.

    Keys not present in map return the defaultValue given in the constructor

    // All keys default to zero.
    const map = new Maps.NumberMap();
    map.get(`hello`); // 0

    To check if a key is present, use has:

    map.has(`hello`); // false

    Math:

    // Adds 1 by default to value of `hello`
    map.add(`hello`);         // 1
    map.multiply(`hello`, 2); // 2 

    // Reset key to default value
    map.reset(`hello`); // 0

    Different default value:

    const map = new Maps.NumberMap(10);
    map.get(`hello`); // 10

    Regular set works, overriding the value to whatever is given:

    map.set(`hello`, 5);
    map.add(`hello`, 2); // 7

    Type Parameters

    • K

    Hierarchy

    • Map<K, number>
      • NumberMap
    Index

    Constructors

    constructor

    Methods

    [iterator] add clear delete deleteKeys divide entries entriesSorted filterKeysByValue findValueMax findValueMin forEach get has keys keysByValue mapValue multiply reset set subtract values groupBy

    Properties

    [toStringTag] defaultValue size [species]

    Constructors

    Methods

    • Returns an iterable of entries in the map.

      Returns MapIterator<[K, number]>

    • Adds an amount to key's value. If key is not found, it is treated as the default value. The new value is set and returned.

      Parameters

      • key: K
      • amount: number = 1

      Returns number

    • Returns void

    • Parameters

      • key: K

      Returns boolean

      true if an element in the Map existed and has been removed, or false if the element does not exist.

    • Divides the value of key by amount. If key is not found, it is treated as the default value. The new value is set and returned.

      Parameters

      • key: K
      • amount: number

      Returns number

    • Returns an iterable of key, value pairs for every entry in the map.

      Returns MapIterator<[K, number]>

    • Iterates over entries, sorted by value. By default ascending order.

      Parameters

      • Optionalsorter: (a: [K, number], b: [K, number]) => number

      Returns Generator<[key: K, value: number]>

    • Iterates over all keys that have a value matching fn.

      // Iterate over all keys that store a value greater than 1
      const greaterThanOne = (v) => v > 1;
      for (const key of map.filterKeysByValue(greaterThanOne)) {
      }

      Parameters

      • fn: (value: number) => boolean

        Predicate to test values

      Returns Generator<K, void, unknown>

    • Returns the largest value in the map. If the map is empty, returns NaN.

      // Eg find all the keys corresponding to the maximum value
      const largestKeys = [...map.keysByValue(map.findValueMax())];

      Returns number

    • Returns the smallest value in the map. If the map is empty, returns NaN.

      // Eg find all the keys corresponding to the minimum value
      const smallestKeys = [...map.keysByValue(map.findValueMin())];

      Returns number

    • Executes a provided function once per each key/value pair in the Map, in insertion order.

      Parameters

      • callbackfn: (value: number, key: K, map: Map<K, number>) => void
      • OptionalthisArg: any

      Returns void

    • Parameters

      • key: K

      Returns boolean

      boolean indicating whether an element with the specified key exists or not.

    • Returns an iterable of keys in the map

      Returns MapIterator<K>

    • Applies a function to all values

      // Round all the values
      map.mapValue((value,key)=> Math.round(value));

      Parameters

      • fn: (value: number, key?: K) => number

      Returns void

    • Multiplies the value of key by amount. If key is not found, it is treated as the default value. The new value is set and returned.

      Parameters

      • key: K
      • amount: number

      Returns number

    • Adds a new element with a specified key and value to the Map. If an element with the same key already exists, the element will be updated.

      Parameters

      • key: K
      • value: number

      Returns this

    • Subtracts an amount from key's value. If key is not found, it is treated as the default value. The new value is set and returned.

      Parameters

      • key: K
      • amount: number = 1

      Returns number

    • Returns an iterable of values in the map

      Returns MapIterator<number>

    • Groups members of an iterable according to the return value of the passed callback.

      Type Parameters

      • K
      • T

      Parameters

      • items: Iterable<T>

        An iterable.

      • keySelector: (item: T, index: number) => K

        A callback which will be invoked for each item in items.

      Returns Map<K, T[]>

    Properties

    "[toStringTag]": string
    defaultValue: number
    size: number

    the number of elements in the Map.

    "[species]": MapConstructor

    Settings

    Member Visibility

    On This Page

    Constructors
    Methods
    Properties