Performs intersection (md_intersect()) and union (md_union()) on,
inter alia, messy date class objects.
For a more typical 'join' that retains all elements, even if duplicated,
please use md_multiset.
e1 %intersect% e2
# S3 method for mdate
%intersect%(e1, e2)
e1 %union% e2
# S3 method for mdate
%union%(e1, e2)Messy date or other class objects
A vector of the same mode for intersect,
or a common mode for union.
%intersect% : Find intersection of sets of messy dates
%union% : Find intersection of sets of messy dates
as_messydate("2012-01-01..2012-01-20") %intersect% as_messydate("2012-01")
#> [1] "2012-01-01" "2012-01-02" "2012-01-03" "2012-01-04" "2012-01-05"
#> [6] "2012-01-06" "2012-01-07" "2012-01-08" "2012-01-09" "2012-01-10"
#> [11] "2012-01-11" "2012-01-12" "2012-01-13" "2012-01-14" "2012-01-15"
#> [16] "2012-01-16" "2012-01-17" "2012-01-18" "2012-01-19" "2012-01-20"
as_messydate("2012-01-01..2012-01-20") %union% as_messydate("2012-01")
#> [1] "2012-01-01" "2012-01-02" "2012-01-03" "2012-01-04" "2012-01-05"
#> [6] "2012-01-06" "2012-01-07" "2012-01-08" "2012-01-09" "2012-01-10"
#> [11] "2012-01-11" "2012-01-12" "2012-01-13" "2012-01-14" "2012-01-15"
#> [16] "2012-01-16" "2012-01-17" "2012-01-18" "2012-01-19" "2012-01-20"
#> [21] "2012-01-21" "2012-01-22" "2012-01-23" "2012-01-24" "2012-01-25"
#> [26] "2012-01-26" "2012-01-27" "2012-01-28" "2012-01-29" "2012-01-30"
#> [31] "2012-01-31"