Warning on POSIXlt (as.POSIXlt (x), ...)

Question

when R issued warning messages on this command

`setwd("~/Desktop/Project R")
Warning message:
In format.POSIXlt(as.POSIXlt(x), ...) :
unknown timezone 'default/Asia/Kolkata'`

So, I tried to create a date for this TZ by typing

as.POSIXct("2017-11-01 10:52", "%Y-%m-%d %H:%M", tz = "Asia/Kolkata")
[1] "2017-11-01 10:52:00 IST"
Warning messages:
1: In strptime(x, format, tz = tz) :
unknown timezone 'default/Asia/Kolkata'
2: In as.POSIXct.POSIXlt(as.POSIXlt(x, tz, ...), tz, ...) :
unknown timezone 'default/Asia/Kolkata'
3: In as.POSIXlt.POSIXct(x, tz) : unknown timezone 'default/Asia/Kolkata'

but warning messages refuse to go? Is there a solution to permanently eliminate these warnings.

Answer 1

I have some kind of problem if your on High Sierra seems to be a mistake between OS HS and R 3.4.2, as this post says https://github.com/stan-dev/rstan/issues/455 Following the instructions (until until R 3.4.3 is finally released), I will work. I AM:

Sys.setenv(TZ="Europe/Madrid")

Now I can download packages and use as.POSIXct, and messages do not appear. Hope this helps!