Convert from excel time number to R POSIXct type.
convertToDateTime(x, origin = "1900-01-01", ...)
Excel stores dates as number of days from some origin date
## 2014-07-01, 2014-06-30, 2014-06-29
x <- c(41821.8127314815, 41820.8127314815, NA, 41819, NaN)
convertToDateTime(x)
#> [1] "2014-07-01 19:30:20 UTC" "2014-06-30 19:30:20 UTC"
#> [3] NA "2014-06-29 00:00:00 UTC"
#> [5] NA
convertToDateTime(x, tz = "Australia/Perth")
#> [1] "2014-07-01 11:30:20 UTC" "2014-06-30 11:30:20 UTC"
#> [3] NA "2014-06-28 16:00:00 UTC"
#> [5] NA
convertToDateTime(x, tz = "UTC")
#> [1] "2014-07-01 19:30:20 UTC" "2014-06-30 19:30:20 UTC"
#> [3] NA "2014-06-29 00:00:00 UTC"
#> [5] NA