Time zones

Working with Dates and Times in R

Charlotte Wickham

Instructor

Time zones

Sys.timezone()

"America/Los_Angeles"

IANA Timezones

OlsonNames()

"Africa/Abidjan"         "Africa/Accra"                    
"Africa/Addis_Ababa"     "Africa/Algiers"                  
"Africa/Asmara"          "Africa/Asmera"                   
"Africa/Bamako"          "Africa/Bangui"
...

length(OlsonNames())

Setting and extracting

mar_11 <- ymd_hms("2017-03-11 12:00:00", 
+     tz = "America/Los_Angeles")
mar_11

"2017-03-11 12:00:00 PST"

tz(mar_11)

"America/Los_Angeles"

Manipulating timezones

force_tz() - change the timezone without changing the clock time

mar_11

"2017-03-11 12:00:00 PST"

force_tz(mar_11, 
    tzone = "America/New_York")

"2017-03-11 12:00:00 EST"

with_tz() - view the same instant in a different timezone

mar_11

"2017-03-11 12:00:00 PST"

with_tz(mar_11, 
    tzone = "America/New_York")

"2017-03-11 15:00:00 EST"

Let's practice!

Working with Dates and Times in R