```
# NOT RUN {
x <- as.Date("2009-09-02")
wday(x) #4
wday(ymd(080101))
wday(ymd(080101), label = TRUE, abbr = FALSE)
wday(ymd(080101), label = TRUE, abbr = TRUE)
wday(ymd(080101) + days(-2:4), label = TRUE, abbr = TRUE)
x <- as.Date("2009-09-02")
yday(x) #245
mday(x) #2
yday(x) <- 1 #"2009-01-01"
yday(x) <- 366 #"2010-01-01"
mday(x) > 3
# }
```

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