Exercise

The ISO-8601 standard

The ISO-8601 standard is the internationally recognized and accepted way to represent dates and times. The standard allows for a common format to not only describe dates, but also to represent ranges and repeating intervals.

xts makes use of this standard for all extract and replace operations. This makes code both easy to write and easy to maintain. It also makes for very concise expression of date ranges and intervals.

For xts to work correctly, it is very important to follow the standard exactly. Details can be found in xts subset and .parseISO8601 documentation.

Which is a valid ISO-8601 string acceptable by xts?

Instructions

50 XP

Possible Answers

"2005-01-02"
"200501"
"2010/02/22"
(1) and (2) only
all of the above