as.POSIXlt
as.POSIXlt('2014-11-04')$wday
POSIXlt
The POSIXlt data type is a vector, and the entries in the vector have the following meanings:
sec 0–61: seconds
min 0–59: minutes
hour 0–23: hours
mday 1–31: day of the month
mon 0–11: months after the first of the year.
year Years since 1900.
wday 0–6 day of the week, starting on Sunday.
yday 0–365: day of the year.
isdst Daylight savings time flag. Positive if in force, zero if not, negative if unknown.