Class: Combination

Defined in: combinations/combination.ts:82

A class representing a combination of values.

The class stores unique values and exposes deterministic sorted values, lexicographic rank helpers, set-style predicates, and ordering helpers.

Param

The values of the combination.

Param

The lexicographic rank of the combination.

Param

The starting offset for combination values.

Examples

const combination = new Combination([12, 3, 42, 6, 22]);
combination.values; // [3, 6, 12, 22, 42]
combination.rank; // 755560

const empty = new Combination();
empty.values; // []
empty.rank; // 0

Extended by

BoundCombination

Constructors

Constructor

new Combination(values?, __namedParameters?): Combination

Defined in: combinations/combination.ts:91

Parameters

values?

CombinationInputWithRank | CombinationInputValues | null

__namedParameters?

CombinationOptions = {}

Returns

Combination

Properties

_rank

protected _rank: number | null

Defined in: combinations/combination.ts:85

_start

protected readonly _start: number

Defined in: combinations/combination.ts:87

_values

protected readonly _values: Set\<number>

Defined in: combinations/combination.ts:83

Accessors

length

Get Signature

get length(): number

Defined in: combinations/combination.ts:180

Get number of values.

Example

new Combination([3, 1, 2]).length; // 3

Returns

number

Number of unique values in the combination.

rank

Get Signature

get rank(): number

Defined in: combinations/combination.ts:155

Get lexicographic rank.

If rank is not explicitly provided, it is computed lazily from values.

Example

new Combination([3, 1, 2]).rank; // 0

Returns

number

Lexicographic rank.

start

Get Signature

get start(): number

Defined in: combinations/combination.ts:192

Get the starting offset of the combination.

Example

new Combination([3, 1, 2], null, 0).start; // 0

Returns

number

Start offset.

storedRank

Get Signature

get storedRank(): number | null

Defined in: combinations/combination.ts:168

Get the stored rank without triggering lazy rank computation.

Returns

number | null

Stored rank or null when it has not been set/computed yet.

values

Get Signature

get values(): CombinationValues

Defined in: combinations/combination.ts:137

Get sorted combination values.

Example

new Combination([3, 1, 2]).values; // [1, 2, 3]

Returns

CombinationValues

Sorted values.

Methods

[iterator]()

[iterator](): Iterator\<number>

Defined in: combinations/combination.ts:444

Returns

Iterator\<number>

compares()

compares(combination): number

Defined in: combinations/combination.ts:358

Compare this combination to another combination or rank.

Parameters

combination

CombinationInput

Candidate combination/rank.

Returns

number

-1, 0, or 1.

Example

new Combination([1, 2, 3]).compares([1, 2, 4]); // -1

copy()

copy(values?): Combination

Defined in: combinations/combination.ts:209

Return a copy with optional modifications.

Parameters

values?

CombinationCopyOptions = {}

Replacement values. null keeps current values. If an integer is provided, it is treated as the lexicographic rank of the combination.

Returns

Combination

A new Combination.

Example

const base = new Combination([4, 5, 6], { start: 1 });
base.copy({ values: [2, 3, 4] }).values; // [2, 3, 4]

equals()

equals(combination): boolean

Defined in: combinations/combination.ts:257

Check whether this combination equals another combination or rank.

Parameters

combination

CombinationInput

Candidate combination/rank.

Returns

boolean

true when values/rank are equal.

Example

const base = new Combination([1, 2, 3]);
base.equals([1, 2, 3]); // true
base.equals(0); // true

get()

get(index): number

Defined in: combinations/combination.ts:408

Get a value by index.

Parameters

index

number

Zero-based value index.

Returns

number

Value at index.

Throws

Thrown when index is out of bounds.

getValues()

getValues(start?): CombinationValues

Defined in: combinations/combination.ts:237

Get values with an optional start offset transformation.

Parameters

start?

number

Optional target start offset.

Returns

CombinationValues

Values adjusted to the requested start offset.

Example

new Combination([1, 2, 3]).getValues(0); // [0, 1, 2]

hashCode()

hashCode(): number

Defined in: combinations/combination.ts:424

Get an integer hash representation.

Returns

number

Rank-based hash.

Example

new Combination([1, 2, 3]).hashCode(); // 0

includes()

includes(combination): boolean

Defined in: combinations/combination.ts:292

Check whether this combination includes another combination or a value.

Parameters

combination

Candidate value(s).

number | CombinationInputValues | null | undefined

Returns

boolean

true when all candidate values are included.

Example

const base = new Combination([2, 4, 6]);
base.includes(4); // true
base.includes([2, 5]); // false

intersection()

intersection(combination): Combination

Defined in: combinations/combination.ts:340

Get the intersection with another combination.

Parameters

combination

Candidate value(s).

CombinationInputValues | null | undefined

Returns

Combination

A new Combination containing shared values.

Example

new Combination([1, 2, 3]).intersection([3, 4, 5]).values; // [3]

intersects()

intersects(combination): boolean

Defined in: combinations/combination.ts:318

Check whether this combination intersects another combination.

Parameters

combination

Candidate value(s).

CombinationInputValues | null | undefined

Returns

boolean

true when at least one value overlaps.

Example

new Combination([1, 2, 3]).intersects([3, 4]); // true

similarity()

similarity(combination): number

Defined in: combinations/combination.ts:388

Calculate similarity ratio with another combination.

Parameters

combination

Candidate values.

CombinationInputValues | null | undefined

Returns

number

Similarity ratio in [0, 1].

Example

new Combination([1, 2, 3]).similarity([2, 3, 4]); // 0.666...

toRepr()

toRepr(): string

Defined in: combinations/combination.ts:436

Return a string representation.

Returns

string

Representation string.

Example

new Combination([1, 2, 3]).toRepr();

toString()

toString(): string

Defined in: combinations/combination.ts:440

Returns

string