TimeInterval

A D3 Time Interval

interface TimeInterval {

(date?: Date): Date;

ceil(date: Date): Date;

filter(test: (date: Date) => boolean): TimeInterval;

floor(date: Date): Date;

offset(date: Date, step?: number): Date;

range(

start: Date,

stop: Date,

step?: number,

): Date[];

round(date: Date): Date;

}

§Call Signatures

(date?: Date): Date

[src]

Returns a new date representing the latest interval boundary date before or equal to date. Equivalent to interval.floor, except it date is not specified, it defaults to the current time. For example, d3.timeYear(date) and d3.timeYear.floor(date) are equivalent.

For example, timeDay(date) typically returns 12:00 AM local time on the given date.

This function is idempotent: if the specified date is already floored to the current interval, a new date with an identical time is returned. Furthermore, the returned date is the minimum expressible value of the associated interval, such that interval.floor(interval.floor(date) - 1) returns the preceding interval boundary date.

Note that the == and === operators do not compare by value with Date objects, and thus you cannot use them to tell whether the specified date has already been floored. Instead, coerce to a number and then compare.

This is more reliable than testing whether the time is 12:00 AM, as in some time zones midnight may not exist due to daylight saving.

§Methods

ceil(date: Date): Date

[src]

Returns a new date representing the earliest interval boundary date after or equal to date.

For example, timeDay.ceil(date) typically returns 12:00 AM local time on the date following the given date.

This method is idempotent: if the specified date is already ceilinged to the current interval, a new date with an identical time is returned. Furthermore, the returned date is the maximum expressible value of the associated interval, such that interval.ceil(interval.ceil(date) + 1) returns the following interval boundary date.

@param date

A date object.

filter(test: (date: Date) => boolean): TimeInterval

[src]

Returns a new interval that is a filtered subset of this interval using the specified test function.

@param test

A test function which is passed a date and should return true if and only if the specified date should be considered part of the interval.

floor(date: Date): Date

[src]

Returns a new date representing the latest interval boundary date before or equal to date.

For example, timeDay.floor(date) typically returns 12:00 AM local time on the given date.

This method is idempotent: if the specified date is already floored to the current interval, a new date with an identical time is returned. Furthermore, the returned date is the minimum expressible value of the associated interval, such that interval.floor(interval.floor(date) - 1) returns the preceding interval boundary date.

This is more reliable than testing whether the time is 12:00 AM, as in some time zones midnight may not exist due to daylight saving.

@param date

A date object.

offset(date: Date, step?: number): Date

[src]

Returns a new date equal to date plus step intervals.

If step is not specified it defaults to 1.

This method does not round the specified date to the interval. For example, if date is today at 5:34 PM, then timeDay.offset(date, 1) returns 5:34 PM tomorrow (even if daylight saving changes!).

@param date

A date object.

@param step

An optional number of steps to apply when calculating the offset date. If step is negative, then the returned date will be before the specified date; if step is zero, then a copy of the specified date is returned; if step is not an integer, it is floored.

range(

start: Date,

stop: Date,

step?: number,

): Date[]

[src]

Returns an array of dates representing every interval boundary after or equal to start (inclusive) and before stop (exclusive).

If step is specified, then every step-th boundary will be returned; for example, for the timeDay interval a step of 2 will return every other day. If step is not an integer, it is floored.

The first date in the returned array is the earliest boundary after or equal to start; subsequent dates are offset by step intervals and floored. Thus, two overlapping ranges may be inconsistent.

To make ranges consistent when a step is specified, use CountableInterval.every instead.

@param start

A start date object for the range.

@param stop

A stop date object for the range.

@param step

An optional number of steps to apply when calculating the dates in the range.

round(date: Date): Date

[src]

Returns a new date representing the closest interval boundary date to date.

For example, timeDay.round(date) typically returns 12:00 AM local time on the given date if it is on or before noon, and 12:00 AM of the following day if it is after noon.

This method is idempotent: if the specified date is already rounded to the current interval, a new date with an identical time is returned.

@param date

A date object.