timechange

Utilities for efficient manipulation of date-time objects while accounting for time-zones and day-light saving times. Supported date time classes are Date, POSIXct, POSIXlt (nanosecond is planned).

Currently implemented:

• time_get: get components (hour, day etc) of date-time objects
• time_update: update date-time objects
• time_round, time_ceiling and time_floor: date-time rounding methods
• time_force_tz, time_at_tz and time_clock_at_tz: updating of time-zones and time/clock extraction at different time-zones
• time_add,time_subtract: fast period arithmetic

When it makes sense functions provide a refined control of what happens in ambiguous situations through roll_month and roll_dst arguments.