Description
===========
This package is intended to manipulate irregular time series such as subtime
series, series based on time intervals, heterogeneous time series (hourly time
series and monthly time series at the same time for instance), etc.

This package uses (and extends) only POSIXt* format for time objects.

Main things defined in this package are the classes POSIXcti, POSIXctp,
TimeIntervalDataFrame, TimeInstantDataFrame, SubtimeDataFrame, methods to
switch from one class to another and the changeSupport method for
TimeIntervalDataFrame.

News

-------------------------------------------------------------------------------
* v1.4.0

The algorithm 'changeSupport' methods has been dispatched into 'split' and
'tapply' methods. Those two types of methods are more user friendly to use since
they correspond to function available in the base package.

For backward compatibility, 'changeSupport' are still defined but now are simply
wrapper to 'tapply' methods. Be aware that default values of arguments are not
necessarily equivalent between 'changeSupport' and 'tapply'.

See man pages to list all methods defined :
help('split', 'timetools')
help('tapply', 'timetools')
help('changeSupport', 'timetools')

-------------------------------------------------------------------------------
* v1.2.1

* a split method for signature(ANY,POSIXst) has been added (actually 
it is a shortcut for "split(x, as.numeric(f))" where f is a POSIXst)
* definition of split methods have been gathered in a unique file
* definition of changeSupport methods have been gathered in a unique file

-------------------------------------------------------------------------------
* V1.2

* 'subtime' class has been replaced by 'POSIXst' class.
* use 'POSIXst' methods to define instance of this class.
* SubtimeDataFrame now rely on 'POSIXst' objects.
* functions 'year', 'month', 'minute', 'second', etc. are now wrappers for the 
'POSIXst' constructor.
* new methods have been added for 'POSIXctp' and 'POSIXcti' objects (tail, head,
summary, split, match, %in%, unique)
* 'natural' mathematical operations between POSIXst (subtimes), POSIXctp (time
periods) and POSIXcti (time intervals) are available.

-------------------------------------------------------------------------------
* v1.1.6 2012-10-30 :
Modification in plotting functions behaviour with the 'pch' argument. Now the
latter can be a data.frame

-------------------------------------------------------------------------------
* v1.1-5 2012-10-05 :

BUG FIX : when timezone property had length > 1, some unwanted errors occur while
manipulating TimeInstantDataFrame.

-------------------------------------------------------------------------------
* v1.1-4 2012-09-27 :

BUG FIX timezone problem with 'start' and 'end' functions for TimeIntervalDataFrame
and with 'when' function for TimeInstantDataFrame.

-------------------------------------------------------------------------------
* V1.1-3 :

When 'changeSupport' or 'RegularTime*DataFrame' were used, an unwanted line could
appear at the end of the Time*DataFrame when the resulting unit was 'year' or
'month'. This behaviour is now fixed and no more unwanted line should appear.

==========
* V1.1-2 :
RegularTimeInstantDataFrame and RegularTimeIntervalDataFrame :
the 'to' argument is no more necessary if 'from', 'by' and 'data' are given.

Bug fix in plot method on the returned parameters

=====================
* 09/03/2012 V1.1-1 :

For 'subtime' functions (and associated), a 'first.day' argument is added. It indicated the first day of week in case of 'wday' subtime.

A 'lapply' function is added for TimeIntervalDataFrame, TimeInstantDataFrame and SubtimeDataFrame.

Plot functions for TimeIntervalDataFrame, TimeInstantDataFrame and SubtimeDataFrame return (invisibly) params used for the plot.

==============
* 07/02/2012 :

The package is now on CRAN. Could take a while to be on all mirrors but already available on some (on French servers it's ok).

To install or update only use :
- install.packages ('timetools')
- update.packages ('timetools')
- or keep downloading it from sourceforge.

