#find list of function in package
ls("package:lubridate")
#output
1] "%--%" "%m-%" "%m+%" "%within%" "add_with_rollback"
[6] "am" "Arith" "as.difftime" "as.duration" "as.interval"
[11] "as.period" "as_date" "as_datetime" "ceiling_date" "Compare"
[16] "cyclic_encoding" "date" "Date" "date_decimal" "date<-"
[21] "day" "day<-" "days" "days_in_month" "ddays"
[26] "decimal_date" "dhours" "dmicroseconds" "dmilliseconds" "dminutes"
[31] "dmonths" "dmy" "dmy_h" "dmy_hm" "dmy_hms"
[36] "dnanoseconds" "dpicoseconds" "dseconds" "dst" "duration"
[41] "dweeks" "dyears" "dym" "epiweek" "epiyear"
[46] "fast_strptime" "fit_to_timeline" "floor_date" "force_tz" "force_tzs"
[51] "format_ISO8601" "guess_formats" "hm" "hms" "hour"
[56] "hour<-" "hours" "int_aligns" "int_diff" "int_end"
[61] "int_end<-" "int_flip" "int_length" "int_overlaps" "int_shift"
[66] "int_standardize" "int_start" "int_start<-" "intersect" "interval"
[71] "is.Date" "is.difftime" "is.duration" "is.instant" "is.interval"
[76] "is.period" "is.POSIXct" "is.POSIXlt" "is.POSIXt" "is.timepoint"
[81] "is.timespan" "isoweek" "isoyear" "lakers" "leap_year"
[86] "local_time" "make_date" "make_datetime" "make_difftime" "mday"
[91] "mday<-" "mdy" "mdy_h" "mdy_hm" "mdy_hms"
[96] "microseconds" "milliseconds" "minute" "minute<-" "minutes"
[101] "month" "month<-" "ms" "my" "myd"
[106] "NA_Date_" "NA_POSIXct_" "nanoseconds" "now" "origin"
[111] "parse_date_time" "parse_date_time2" "period" "period_to_seconds" "picoseconds"
[116] "pm" "POSIXct" "pretty_dates" "qday" "qday<-"
[121] "quarter" "reclass_date" "reclass_timespan" "rollback" "rollbackward"
[126] "rollforward" "round_date" "second" "second<-" "seconds"
[131] "seconds_to_period" "semester" "setdiff" "show" "stamp"
[136] "stamp_date" "stamp_time" "time_length" "today" "tz"
[141] "tz<-" "union" "wday" "wday<-" "week"
[146] "week<-" "weeks" "with_tz" "yday" "yday<-"
[151] "ydm" "ydm_h" "ydm_hm" "ydm_hms" "year"
[156] "year<-" "years" "ym" "ymd" "ymd_h"
[161] "ymd_hm" "ymd_hms" "yq"
>