Creating calendars with calendar

Robin Lovelace

2024-04-28

calendar allows you to read-in ‘ical files’ (which typically have the .ics filetype) with ic_read(). However, often it’s useful to create your own ical object from scratch. The purpose of this vignette is to show how, with reference to a real-world application: creating a timetable for a new module.

It assumes you’ve installed the package following instructions in the README and have attached it as follows:

library(calendar)

Creating events

The building blocks of most calendars the event. All events have a start point and an end point (unless they are an all day event) and a summary description. As shown in the example below, they also tend to contain other fields.

# key:value pairs in an ical example:
ic_list(ical_example)[[1]]
#>  [1] "DTSTART:20180809T160000Z"                 
#>  [2] "DTEND:20180809T163000Z"                   
#>  [3] "DTSTAMP:20180810T094100Z"                 
#>  [4] "UID:1119ejg4vug5758527atjcrqj3@google.com"
#>  [5] "CREATED:20180807T133712Z"                 
#>  [6] "DESCRIPTION:\\n"                          
#>  [7] "LAST-MODIFIED:20180807T133712Z"           
#>  [8] "LOCATION:"                                
#>  [9] "SEQUENCE:0"                               
#> [10] "STATUS:CONFIRMED"                         
#> [11] "SUMMARY:ical programming mission"         
#> [12] "TRANSP:OPAQUE"

Fortunately you don’t need to specify all of these when creating events because some will be created manually and some are not necessary. Events can be created as follows (this one creates a 5 day trip):

library(calendar)
s = as.POSIXct("2019-01-12")
e = s + 60^2 * 24 *5
event = ic_event(start = s, end = e , summary = "Research trip")
event
#> # A tibble: 1 × 4
#>   UID                            DTSTART             DTEND               SUMMARY
#>   <chr>                          <dttm>              <dttm>              <chr>  
#> 1 ical-f8d6a988-ab33-4964-928f-… 2019-01-12 00:00:00 2019-01-17 00:00:00 Resear…
class(event)
#> [1] "ical"       "tbl_df"     "tbl"        "data.frame"
ic_character(event)
#>  [1] "BEGIN:VCALENDAR"                              
#>  [2] "PRODID:-//ATFutures/ical //EN"                
#>  [3] "VERSION:2.0"                                  
#>  [4] "CALSCALE:GREGORIAN"                           
#>  [5] "METHOD:PUBLISH"                               
#>  [6] "BEGIN:VEVENT"                                 
#>  [7] "UID:ical-f8d6a988-ab33-4964-928f-e0a784693b43"
#>  [8] "DTSTART:20190112T000000"                      
#>  [9] "DTEND:20190117T000000"                        
#> [10] "SUMMARY:Research trip"                        
#> [11] "END:VEVENT"                                   
#> [12] "END:VCALENDAR"