LongCount

Long Count cycle.

The Long Count is a mixed-radix numeral system used by the ancient Maya to track days elapsed since a creation-era base date. This implementation uses the standard epoch per scholarly literature [R1, R2]:

Epoch (Maya Day Number (MDN) = 0): 13.0.0.0.0 4 Ajaw 8 Kumk'u

This date represents the completion of the 13th bak'tun in Maya cosmology and serves as the anchor for all Long Count calculations and correlation with Western calendars. MDN is analogous to Julian Day Number, but for the Maya calendar system.

Units (mixed-radix system):

1 k'in = 1 day
1 winal = 20 k'in
1 tun = 18 winal = 360 days
1 k'atun = 20 tun = 7,200 days
1 bak'tun = 20 k'atun = 144,000 days

See

Reingold, Dershowitz, & Clamen (1993) [R1]
Martin & Skidmore (2012) [R2]

Extends

DistanceNumber

Constructors

Constructor

new LongCount(...cycles): LongCount

Defined in: lc/long-count.ts:219

Parameters

cycles

...(number | Wildcard)[]

Components in the long count (eg, K'in, Winal, Bak'tun, etc)

Returns

LongCount

Overrides

DistanceNumber.constructor

Properties

comment

comment: Comment

Defined in: comment-wrapper.ts:11

Attached comment.

Inherited from

DistanceNumber.comment

datePattern

datePattern: RegExp

Defined in: lc/distance-number.ts:12

Inherited from

DistanceNumber.datePattern

parts

parts: (number | Wildcard)[]

Defined in: lc/distance-number.ts:11

Inherited from

DistanceNumber.parts

sign

sign: number

Defined in: lc/distance-number.ts:13

Inherited from

DistanceNumber.sign

Accessors

bakTun

Get Signature

get bakTun(): number | Wildcard

Defined in: lc/distance-number.ts:262

Return the bak'tun component of the fullDate

Returns

number | Wildcard

Set Signature

set bakTun(newBakTun): void

Defined in: lc/distance-number.ts:254

Set the bak'tun component of the fullDate

Parameters

newBakTun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.bakTun

gregorian

Get Signature

get gregorian(): GregorianCalendarDate

Defined in: lc/long-count.ts:261

Return a Gregorian representation of this long count date, offset by the correlation constant.

Returns

GregorianCalendarDate

isNegative

Get Signature

get isNegative(): boolean

Defined in: lc/distance-number.ts:60

Return true if the Long Count is operating as a negative Distance Number.

Returns

boolean

Set Signature

set isNegative(newNegative): void

Defined in: lc/distance-number.ts:76

Set this Long Count as being a negative Distance Number

Parameters

newNegative

boolean

Returns

void

Inherited from

DistanceNumber.isNegative

isPositive

Get Signature

get isPositive(): boolean

Defined in: lc/distance-number.ts:52

Return true if the Long Count is positive.

Returns

boolean

Set Signature

set isPositive(newPositive): void

Defined in: lc/distance-number.ts:68

Set this Long Count as being a Long Count or a positive Distance Number

Parameters

newPositive

boolean

Returns

void

Inherited from

DistanceNumber.isPositive

julian

Get Signature

get julian(): JulianCalendarDate

Defined in: lc/long-count.ts:269

Return a Julian representation of this long count date, offset by the correlation constant.

Returns

JulianCalendarDate

julianDay

Get Signature

get julianDay(): number

Defined in: lc/long-count.ts:253

Return a representation of this Long Count in Julian Days.

Returns

number

kalabtun

Get Signature

get kalabtun(): number | Wildcard

Defined in: lc/distance-number.ts:292

Return the kalabtun component of the fullDate

Returns

number | Wildcard

Set Signature

set kalabtun(newBakTun): void

Defined in: lc/distance-number.ts:284

Set the kalabtun component of the fullDate

Parameters

newBakTun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.kalabtun

kAtun

Get Signature

get kAtun(): number | Wildcard

Defined in: lc/distance-number.ts:247

Return the k'atun component of the fullDate

Returns

number | Wildcard

Set Signature

set kAtun(newKAtun): void

Defined in: lc/distance-number.ts:239

Set the k'atun component of the fullDate

Parameters

newKAtun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.kAtun

kIn

Get Signature

get kIn(): number | Wildcard

Defined in: lc/distance-number.ts:202

Return the k'in component of the fullDate

Returns

number | Wildcard

Set Signature

set kIn(newKIn): void

Defined in: lc/distance-number.ts:194

Set the k'in component of the fullDate

Parameters

newKIn

number | Wildcard

Returns

void

Inherited from

DistanceNumber.kIn

kinchiltun

Get Signature

get kinchiltun(): number | Wildcard

Defined in: lc/distance-number.ts:307

Return the kinchiltun component of the fullDate

Returns

number | Wildcard

Set Signature

set kinchiltun(newBakTun): void

Defined in: lc/distance-number.ts:299

Set the kinchiltun component of the fullDate

Parameters

newBakTun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.kinchiltun

lordOfNight

Get Signature

get lordOfNight(): LordOfTheNight

Defined in: lc/long-count.ts:285

Returns

LordOfTheNight

piktun

Get Signature

get piktun(): number | Wildcard

Defined in: lc/distance-number.ts:277

Return the piktun component of the fullDate

Returns

number | Wildcard

Set Signature

set piktun(newBakTun): void

Defined in: lc/distance-number.ts:269

Set the piktun component of the fullDate

Parameters

newBakTun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.piktun

sigParts

Get Signature

get sigParts(): (number | Wildcard)[]

Defined in: lc/distance-number.ts:120

Only digits in the LC with significant digits

Returns

(number | Wildcard)[]

Inherited from

DistanceNumber.sigParts

tun

Get Signature

get tun(): number | Wildcard

Defined in: lc/distance-number.ts:232

Return the tun component of the fullDate

Returns

number | Wildcard

Set Signature

set tun(newTun): void

Defined in: lc/distance-number.ts:224

Set the tun component of the fullDate

Parameters

newTun

number | Wildcard

Returns

void

Inherited from

DistanceNumber.tun

winal

Get Signature

get winal(): number | Wildcard

Defined in: lc/distance-number.ts:217

Return the winal component of the fullDate

Returns

number | Wildcard

Set Signature

set winal(newWinal): void

Defined in: lc/distance-number.ts:209

Set the winal component of the fullDate

Parameters

newWinal

number | Wildcard

Returns

void

Inherited from

DistanceNumber.winal

Methods

appendComment()

appendComment(comment): this

Defined in: comment-wrapper.ts:42

Append additional text to the current comment.

Parameters

comment

string | Comment

Returns

this

Inherited from

DistanceNumber.appendComment

asDistanceNumber()

asDistanceNumber(): DistanceNumber

Defined in: lc/long-count.ts:340

Return this Long Count as a Distance Number

Returns

DistanceNumber

buildCalendarRound()

buildCalendarRound(): CalendarRound

Defined in: lc/long-count.ts:295

Returns

CalendarRound

buildFullDate()

buildFullDate(): FullDate

Defined in: lc/long-count.ts:305

Returns

FullDate

FullDate

clone()

clone(): LongCount

Defined in: lc/long-count.ts:277

Create a copy object of this long count fullDate

Returns

LongCount

Overrides

DistanceNumber.clone

commentIsEqual()

commentIsEqual(otherCommentWrapper): boolean

Defined in: comment-wrapper.ts:60

Compare this wrapper's comment against another wrapper.

Parameters

otherCommentWrapper

CommentWrapper

Returns

boolean

Inherited from

DistanceNumber.commentIsEqual

equal()

equal(other): boolean

Defined in: lc/long-count.ts:351

Compare two Long Count dates for equality. Unlike DistanceNumber.equal(), this compares all parts, handling trailing zeros correctly. This ensures dates with k'in=0 are compared correctly (e.g., 0.0.0.0.0 vs 0.2.12.13.0).

Parameters

other

IPart

Returns

boolean

Overrides

DistanceNumber.equal

equalWithComment()

equalWithComment(otherCommentWrapper): boolean

Defined in: comment-wrapper.ts:67

Check equality including the associated comment.

Parameters

otherCommentWrapper

IPart

Returns

boolean

Inherited from

DistanceNumber.equalWithComment

exactlyEqual()

exactlyEqual(other): boolean

Defined in: lc/distance-number.ts:107

Given two long count dates, check if they are exactly equal

Parameters

other

DistanceNumber

Returns

boolean

Inherited from

DistanceNumber.exactlyEqual

getDateSections()

getDateSections(index): number | Wildcard

Defined in: lc/distance-number.ts:145

Get specific column in Long Count fullDate

Parameters

index

number

Returns

number | Wildcard

Inherited from

DistanceNumber.getDateSections

getPosition()

getPosition(): number

Defined in: lc/distance-number.ts:332

Count the number of days since 0.0.0.0.0 for this LC.

Returns

number

Inherited from

DistanceNumber.getPosition

gt()

gt(newLongCount): boolean

Defined in: lc/distance-number.ts:187

Compare is this LC is less than the supplied LC.

Parameters

newLongCount

DistanceNumber

Returns

boolean

Inherited from

DistanceNumber.gt

isPartial()

isPartial(): boolean

Defined in: lc/distance-number.ts:324

Returns true if any of the positions in the Long Count have been assigned a Wildcard object.

Returns

boolean

Inherited from

DistanceNumber.isPartial

isValid()

isValid(): boolean

Defined in: lc/distance-number.ts:315

Ensure the fullDate has only numbers and wildcards separated by points.

Returns

boolean

Inherited from

DistanceNumber.isValid

lt()

lt(newLongCount): boolean

Defined in: lc/distance-number.ts:178

Compare if this LC is greater than the supplied LC.

Parameters

newLongCount

DistanceNumber

Returns

boolean

Inherited from

DistanceNumber.lt

map()

map(fn): any[]

Defined in: lc/distance-number.ts:169

Pass the map down to the parts

Parameters

fn

(lcPart, lcPartIndex) => any

Returns

any[]

Inherited from

DistanceNumber.map

minus()

minus(newLc): LongcountSubtraction

Defined in: lc/long-count.ts:329

Return the difference between this Long Count and the supplied

Parameters

newLc

LongCount

Returns

LongcountSubtraction

Overrides

DistanceNumber.minus

normalise()

normalise(): DistanceNumber

Defined in: lc/distance-number.ts:399

Make sure the elements of the Long Count do not exceed their valid ranges. Converts the Long Count to total days, then decomposes back to normalized form with proper carry/borrow per the mixed-radix system [R1, R2]:

k'in ∈ [0,19]
winal ∈ [0,17] (18 winal = 1 tun)
tun ∈ [0,19]
k'atun ∈ [0,19]
bak'tun and higher are unbounded

Returns

DistanceNumber

Inherited from

DistanceNumber.normalise

plus()

plus(newLc): LongcountAddition

Defined in: lc/long-count.ts:317

Return the sum of this Long Count and the supplied

Parameters

newLc

LongCount

Returns

LongcountAddition

Overrides

DistanceNumber.plus

resetComment()

resetComment(): this

Defined in: comment-wrapper.ts:20

Reset the current comment back to an empty comment.

Returns

this

Inherited from

DistanceNumber.resetComment

setComment()

setComment(comment): this

Defined in: comment-wrapper.ts:28

Replace the current comment.

Parameters

comment

string | Comment

Returns

this

Inherited from

DistanceNumber.setComment

setCorrelationConstant()

setCorrelationConstant(newConstant): LongCount

Defined in: lc/long-count.ts:244

Chainable method to set the correlation constant

Parameters

newConstant

CorrelationConstant

Returns

LongCount

setDateSections()

setDateSections(index, newValue): LongCount

Defined in: lc/distance-number.ts:159

Set specific column in Long Count fullDate

Parameters

index

number

newValue

number | Wildcard

Returns

LongCount

Inherited from

DistanceNumber.setDateSections

toString()

toString(): string

Defined in: lc/distance-number.ts:454

Convert the LongCount to a string and pad the sections of the fullDate

Returns

string

Inherited from

DistanceNumber.toString

fromDistanceNumber()

static fromDistanceNumber(dn): LongCount

Defined in: lc/long-count.ts:39

Parameters

dn

DistanceNumber

Returns

LongCount

fromGregorian()

static fromGregorian(gregorian, correlation?): LongCount

Defined in: lc/long-count.ts:74

Create a Long Count from a Gregorian date.

Accepts JavaScript Date objects or ISO 8601 date strings and converts them to the corresponding Maya Long Count date using the specified correlation constant. The default correlation (584283, original GMT) is used unless specified otherwise.

Important: This method uses the proleptic Gregorian calendar for all dates, including historical dates before the Gregorian calendar was adopted in 1582. JavaScript Date objects always use the proleptic Gregorian calendar. Only the date portion is used; any time components are ignored.

Supports ISO 8601 date format: "YYYY-MM-DD" (e.g., "2012-12-21")

Parameters

gregorian

string | Date

JavaScript Date object or ISO 8601 date string

correlation?

CorrelationConstant = ...

Correlation constant for alignment (default: 584283 GMT)

Returns

LongCount

A Long Count instance representing the same date

Throws

If the date is invalid or results in a negative Maya Day Number

Example

// From JavaScript Date object
const date = new Date('2012-12-21');
const lc1 = LongCount.fromGregorian(date);
console.log(lc1.toString()); // "13. 0. 0. 0. 0"

// From ISO 8601 date string
const lc2 = LongCount.fromGregorian('2012-12-21');
console.log(lc2.toString()); // "13. 0. 0. 0. 0"

fromJulianDay()

static fromJulianDay(julianDay, correlation?): LongCount

Defined in: lc/long-count.ts:132

Create a Long Count from a Julian Day Number.

Converts a Julian Day Number to the corresponding Maya Long Count date using the specified correlation constant. The Maya Day Number (MDN) is calculated as: MDN = JDN - correlation_constant.

Parameters

julianDay

number

The Julian Day Number to convert

correlation?

CorrelationConstant = ...

Correlation constant for alignment (default: 584283 GMT)

Returns

LongCount

A Long Count instance representing the same date

Throws

If the resulting Maya Day Number is negative

Example

const lc = LongCount.fromJulianDay(2456283);
console.log(lc.toString()); // "13. 0. 0. 0. 0"

fromMayanDayNumber()

static fromMayanDayNumber(mayanDayNumber, correlation?): LongCount

Defined in: lc/long-count.ts:162

Create a Long Count from a Maya Day Number (days since 0.0.0.0.0).

Converts a Maya Day Number (total days elapsed since the creation date) into the corresponding Long Count notation using the mixed-radix system:

k'in (base 20)
winal (base 18)
tun, k'atun, bak'tun (base 20)

Parameters

mayanDayNumber

number

Days elapsed since 0.0.0.0.0 (must be non-negative)

correlation?

CorrelationConstant

Optional correlation constant to set on the result

Returns

LongCount

A Long Count instance representing the date

Throws

If mayanDayNumber is negative

Example

const lc = LongCount.fromMayanDayNumber(1872000); // 13.0.0.0.0
console.log(lc.toString()); // "13. 0. 0. 0. 0"

See​

Extends​

Constructors​

Constructor​

Parameters​

cycles​

Returns​

Overrides​

Properties​

comment​

Inherited from​

datePattern​

Inherited from​

parts​

Inherited from​

sign​

Inherited from​

Accessors​

bakTun​

Get Signature​

Returns​

Set Signature​

Parameters​

newBakTun​

Returns​

Inherited from​

gregorian​

Get Signature​

Returns​

isNegative​

Get Signature​

Returns​

Set Signature​

Parameters​

newNegative​

Returns​

Inherited from​

isPositive​

Get Signature​

Returns​

Set Signature​

Parameters​

newPositive​

Returns​

Inherited from​

julian​

Get Signature​

Returns​

julianDay​

Get Signature​

Returns​

kalabtun​

Get Signature​

Returns​

Set Signature​

Parameters​

newBakTun​

Returns​

Inherited from​

kAtun​

Get Signature​

Returns​

Set Signature​

Parameters​

newKAtun​

Returns​

Inherited from​

kIn​

Get Signature​

Returns​

Set Signature​

Parameters​

newKIn​

Returns​

Inherited from​

kinchiltun​

Get Signature​

Returns​

Set Signature​

Parameters​

See

Extends

Constructors

Constructor

Parameters

cycles

Returns

Overrides

Properties

comment

Inherited from

datePattern

Inherited from

parts

Inherited from

sign

Inherited from

Accessors

bakTun

Get Signature

Returns

Set Signature

Parameters

newBakTun

Returns

Inherited from

gregorian

Get Signature

Returns

isNegative

Get Signature

Returns

Set Signature

Parameters

newNegative

Returns

Inherited from

isPositive

Get Signature

Returns

Set Signature

Parameters

newPositive

Returns

Inherited from

julian

Get Signature

Returns

julianDay

Get Signature

Returns

kalabtun

Get Signature

Returns

Set Signature

Parameters

newBakTun

Returns

Inherited from

kAtun

Get Signature

Returns

Set Signature

Parameters

newKAtun

Returns

Inherited from

kIn

Get Signature

Returns

Set Signature

Parameters

newKIn

Returns

Inherited from

kinchiltun

Get Signature

Returns

Set Signature

Parameters