Logical operations on messy dates
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 >= e2Functions
<: tests whether the dates in the first vector precede the dates in the second vector. ReturnsNAwhen the date order can't be determined.>: tests whether the dates in the first vector succeed the dates in the second vector. ReturnsNAwhen 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. ReturnsNAwhen 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. ReturnsNAwhen 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