我用lubridate,觉得这很简单
ymd("2010-01-31")+months(0:23)
但看看你得到了什么.一切都搞砸了!
[1] "2010-01-31 UTC" "2010-03-03 UTC" "2010-03-31 UTC" "2010-05-01 UTC" "2010-05-31 UTC" "2010-07-01 UTC" "2010-07-31 UTC" "2010-08-31 UTC" "2010-10-01 UTC"
[10] "2010-10-31 UTC" "2010-12-01 UTC" "2010-12-31 UTC" "2011-01-31 UTC" "2011-03-03 UTC" "2011-03-31 UTC" "2011-05-01 UTC" "2011-05-31 UTC" "2011-07-01 UTC"
[19] "2011-07-31 UTC" "2011-08-31 UTC" "2011-10-01 UTC" "2011-10-31 UTC" "2011-12-01 UTC" "2011-12-31 UTC"
然后我读了lubridate如何迎合间隔、持续时间和周期等现象.我知道一个月实际上是(365*4+1)/48=30.438天定义的天数.所以我试着聪明点,把它改写成
ymd("2010-01-31")+ as.period(months(0:23))
但这只是一个错误.
Error in as.period.default(months(0:23)) : (list) object cannot be coerced to type 'double'