Skip to contents

Logical operations on messy dates

Source: R/operate_comparison.R
operate_inequalities.Rd

These operators (<, >, <=, >=) compare mdate objects with each other, or with Date/POSIXct/POSIXlt objects, by comparing the range of dates each side could represent (its minimum and maximum), rather than requiring a single, precise value on both sides. A comparison returns NA wherever the two ranges overlap and the order cannot be determined; see the examples below. For a measure of how much of one side precedes or follows the other, rather than a strict TRUE/FALSE/NA, see ?operate_proportional.

Usage

# S3 method for class 'mdate'
e1 < e2

# S3 method for class 'mdate'
e1 > e2

# S3 method for class 'mdate'
e1 <= e2

# S3 method for class 'mdate'
e1 >= e2

Arguments

e1, e2

mdate or other class objects

Value

A logical vector the same length as the longer of e1 and e2.

Functions

  • < : tests whether the dates in the first vector precede the dates in the second vector. Returns NA when the date order can't be determined.

  • > : tests whether the dates in the first vector succeed the dates in the second vector. Returns NA when the date order can't be determined.

  • <= : tests whether the dates in the first vector are equal to or precede the dates in the second vector. Returns NA when the date order can't be determined.

  • >= : tests whether the dates in the first vector are equal to or succeed the dates in the second vector. Returns NA when the date order can't be determined.

Examples

as_messydate("2012-06-02") > as.Date("2012-06-01") # TRUE
#> [1] TRUE
# 2012-06-XX could mean 2012-06-03, so unknown if it comes before 2012-06-02
as_messydate("2012-06-XX") < as.Date("2012-06-02") # NA
#> [1] NA
# But 2012-06-XX cannot be before 2012-06-01
as_messydate("2012-06-XX") >= as.Date("2012-06-01") # TRUE
#> [1] TRUE
# times of day are compared for two dates on the same day
as_messydate("2012-06-02 09:00") < as_messydate("2012-06-02 17:00") # TRUE
#> [1] TRUE