time_gcd_diff {timeplyr}

Fast greatest common divisor of time differences

Description

Fast greatest common divisor of time differences

Usage

time_gcd_diff(
  x,
  time_by = NULL,
  time_type = getOption("timeplyr.time_type", "auto"),
  tol = sqrt(.Machine$double.eps)
)

Arguments

x

Time variable.
Can be a Date, POSIXt, numeric, integer, yearmon, or yearqtr.

time_by

Time unit.
Must be one of the following:

• string, specifying either the unit or the number and unit, e.g time_by = "days" or time_by = "2 weeks"

• named list of length one, the unit being the name, and the number the value of the list, e.g. list("days" = 7). For the vectorized time functions, you can supply multiple values, e.g. list("days" = 1:10).

• Numeric vector. If time_by is a numeric vector and x is not a date/datetime, then arithmetic is used, e.g time_by = 1.

time_type

If "auto", periods are used if x is a Date and durations are used if x is a datetime. Otherwise numeric differences are calculated.

tol

Numeric tolerance for gcd algorithm.

Value

A list of length 1.

Examples

library(timeplyr)
library(lubridate)
library(cppdoubles)

time_gcd_diff(1:10)
time_gcd_diff(seq(0, 1, 0.2))

time_gcd_diff(time_seq(today(), today() + 100, time_by = "3 days"))
time_gcd_diff(time_seq(now(), len = 10^2, time_by = "125 seconds"))

# Monthly gcd using lubridate periods
quarter_seq <- time_seq(today(), len = 24, time_by = months(4))
time_gcd_diff(quarter_seq, time_by = months(1), time_type = "period")
time_gcd_diff(quarter_seq, time_by = "months", time_type = "duration")

# Detects monthly granularity
double_equal(time_gcd_diff(as.vector(time(AirPassengers))), 1/12)