tind: A Common Representation of Time Indices of Different Types

In tind: A Common Representation of Time Indices of Different Types

A Common Representation of Time Indices of Different Types

Description

tind is an S3 class representing time indices of different types (years, quarters, months, ISO 8601 weeks, dates, date-time, and arbitrary integer/numeric indices). Time indices are represented by vectors of integers or doubles with type attribute and time zone attribute (date-time only). Objects of tind behave like plain vectors and can be easily used in data frames.

A tind object would usually be created using as.tind method or using parse_t and strptind functions. tind constructor allows to create time indices from components (like year, month, day) and to create vectors of a given length filled with NA values.

is.tind function checks whether an object is of tind class.

Usage

tind(..., length = 0L, type = NULL, tz = NULL)

is.tind(x)

Arguments

...	components of time index to be constructed (in arbitrary order), the following are accepted: y year. q quarter. m month. w week (ISO 8601). d day. j day of year. u day of week (ISO 8601). H hour. M minute. S second.
length	an integer value specifying the desired length.
type	a character value determining time index type (y - years, q - quarters, m - months, w - weeks, d - dates, t - date-time, h - time of day, n - numeric value, i - integer value).
tz	(optional) a character value determining the time zone (the default NULL is interpreted as the system time zone). See tzone documentation for information on time zones.
x	any R object.

Details

tind class supports the following types of time indices:

years

internal code "y".

quarters

internal code "q".

months

internal code "m".

weeks

internal code "w".

dates

internal code "d".

date-time

internal code "t".

time of day

internal code "h".

arbitrary integer index

"i".

arbitrary numeric index

"n".

Valid ranges for time indices are:

years ("y")

0000–9999.

quarters ("q")

0000q1–9999q4.

months ("m")

0000-01–9999-12.

weeks ("w")

0000-W01–9999-W52.

dates ("d")

0000-01-01–9999-12-31.

date-time ("t")

from 0000-01-01 15:00:00Z to 9999-12-31 09:00:00Z (between -62167165200 and 253402246800 seconds since the Unix epoch).

time of day ("h")

from 00:00 to 24:00 (between 0 and 86400 seconds since midnight).

Value

An object of tind class for tind or a logical value for is.tind.

See Also

as.tind for conversion to tind, parse_t and strptind functions for parsing character strings, date_time for construction of date-time indices from date and time components, tind-methods for basic methods.

Examples

# years
tind(y = 2010:2020)
tind(type = "y")
tind(length = 11, type = "y")

# quarters
tind(y = rep(2020:2023, each = 4), q = 1:4)
tind(q = 1:4, y = rep(2020:2023, each = 4))
tind(type = "q")
tind(length = 4, type = "q")

# months
tind(y = 2023, m = 1:12)
tind(m = 1:12, y = 2023)
tind(type = "m")
tind(length = 12, type = "m")

# weeks
tind(y = 2024, w = 1 + 2 * (0:25))
tind(type = "w")
tind(length = 13, type = "w")

# dates
tind(m = 3, d = 15, y = 2024)
tind(y = 2024, m = rep(1:3, each = 2), d = c(1, 15))
tind(type = "d")
tind(length = 6, type = "d")

# time of day
tind(H = 16, M = (0:3) * 15)
tind(type = "h")
tind(length = 4, type = "h")

# date-time
# system time zone
tind(y = 2024, m = 8, d = 2, H = 16, M = (0:3) * 15)
tind(y = 2024, m = 8, d = 2, H = 16, M = (0:3) * 15)
tind(y = 2024, m = 8, d = 2, H = 16, M = 0, S = 10 * (0:5))
# time zone explicitly provided
tind(y = 2024, m = 8, d = 2, H = 16, M = (0:3) * 15, tz = "UTC")
tind(type = "t")
tind(type = "t", tz = "UTC")
tind(length = 4, type = "t")
tind(length = 4, type = "t", tz = "UTC")

# integer and numeric indices
# (cannot be constructed from components like above)
tind(length = 10, type = "i")
tind(length = 10, type = "n")

tind documentation built on Dec. 28, 2025, 1:06 a.m.