Have you seen the ITime class (also IDate and IDateTime)? Meant for this purpose.
On 14 August 2011 21:44, Leon Baum <[email protected]> wrote: > > Hello, > > I understand the performance reasons for requiring the key to be of > integer type, but I often would like to use data.table's joining and > grouping features with millisecond POSIXct timestamps. > > One workaround is to convert the timestamps to an integer representing > the milliseconds since the first timestamp, but for time ranges of > larger than a few weeks, the number of milliseconds is larger than what > can be stored in a 32-bit integer. > > I see two possible solutions: > > 1. Store the integer milliseconds as numeric type, which allows 64-bit > integers to be stored exactly. This solution would simply require an > option for data.table to assume that a numeric type is actually storing > integer values. > > 2. Add a second, slower, sorting algorithm to data.table that could > handle non-integer values. This solution would allow POSIXct types to be > used directly by data.table. > > Are either of these solutions possible and reasonable? Or is there some > workaround I'm missing to be able to use larger-than-32-bit integers as > keys? > > -Leon > _______________________________________________ > datatable-help mailing list > [email protected] > https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help > _______________________________________________ datatable-help mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
