Combine data that have timezones
Recall that xts objects store the time index as seconds since midnight, 1970-01-01 in the UTC timezone. merge()
uses this underlying index and returns a result with the first object's timezone.
This exercise provides an example. The two objects in your workspace are identical except for the index timezone. The index values are the same instances in time, but measured in different locations. The london
object's timezone is Europe/London and the chicago
object's timezone is America/Chicago.
This exercise is part of the course
Importing and Managing Financial Data in R
Exercise instructions
- Fill in the object names so the result of the
merge()
will have a London timezone. - Use
str()
to look at the structure oftz_london
and note theTZ
and the local time range printed in the first line of output. - Now complete the
merge()
command so the result will have a Chicago timezone. - Use
str()
to look at the structure oftz_chicago
and note how theTZ
and local time range have changed.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Create merged object with a London timezone
tz_london <- merge(___, ___)
# Look at tz_london structure
# Create merged object with a Chicago timezone
tz_chicago <- merge(___, ___)
# Look at tz_chicago structure