Class attributes - tclass, tzone, and tformat

xts objects are somewhat tricky when it comes to time. Internally, we have now seen that the index attribute is really a vector of numeric values corresponding to the seconds since the UNIX epoch (1970-01-01).

How these values are displayed on printing and how they are returned to the user when using the index() function is dependent on a few key internal attributes.

The information that controls this behavior can be viewed and even changed through a set of accessor functions detailed here:

The index class using indexClass() (e.g. from Date to chron)
The time zone using indexTZ() (e.g. from America/Chicago to Europe/London)
The time format to be displayed via indexFormat() (e.g. YYYY-MM-DD)

In this exercise, you will practice each of these functions and view the results of your changes. To do so, you'll once again use the temps data that has been pre-loaded into your workspace.

View the first three rows of the index in the current temps data.
Find the index class of temps using the most relevant command above.
Find the time zone of temps, again using the most relevant command above.
Change the index format of temps to "%b-%d-%Y".
View the new index format using head().

Take Hint (-30 XP)

Exercise

Class attributes - tclass, tzone, and tformat

Instructions