0.3-6	18-Oct-2012
        o 'vector2zoo' : -) now it handles sub-daily values 
                         -) 'dates' argument accepts 'POSIXct' & 'POSIXlt' objects
        o 'izoo2rzoo'  : -) now it handles sub-daily values 
                         -) 'dates' argument accepts 'POSIXct' & 'POSIXlt' objects
        o 'sfreq'      : was transformed into a wrapper to the 'xts::periodicity' function, in order to allow identification of more
                         sampling frequencies: 'minute', 'hourly', 'daily', 'weekly', 'monthly', 'quarterly' and 'annual' (instead of 
                         'yearly' as used in xts)
        o 'fdc'        : zero discharge value(s) are now removed ONLY when 'log="y"' AND 'plot=TRUE' (both default values of the function).
                         Up to hydroTSM 0.3-5, zero values were removed when 'log="y"' (default value of the function), even if 'plot=FALSE' 
                         (thanks to Giovanni Forzieri !)
        o 'sname2ts'   : now it works with date.fmt="%Y%m%d" (e.g. 20000101), which were previously interpreted as numbers and not as dates, 
                         leading to an error (thanks to Vishnu Pandey !)
        o 'sname2plot' : now it works with date.fmt="%Y%m%d" (e.g. 20000101), which were previously interpreted as numbers and not as dates, 
                         leading to an error
        o 'hydrokrige' : fixed interpolation error raised for some constant value maps
        o DESCRIPTION  : 'Author@R' field was replaced by 'Authors@R'          

0.3-5	04-Jul-2012
        o 'dwi.zoo'                  : fixed display error for years and months when 'matrixplot' is used to plot the results of 'dwi' 
                                       applied to a matrix or data.frame.
                                       This error appeared after an update of the zoo package, and did not imply any error in the 
                                       computation, only in the display of the years/months
        o 'izoo2rzoo.zoo'            : now works properly with matrix and data.frame objects 
        o 'hypsometric'              : now is able to deal with raster objects with more than 1 band 
                                       (thanks to Jan Schwanbeck for reporting the issue and proposing a solution) 
        o 'daily2monthly.data.frame' : -) calls to 'as.Date' were changed to 'zoo::as.Date', to avoid possible conflicts with zoo >= 1.7-2
                                       -) wrong labelling of months was fixed (only occurred when out.type="db")
        o 'daily2annual.data.frame'  : -) calls to 'as.Date' were changed to 'zoo::as.Date', to avoid possible conflicts with zoo >= 1.7-2
        o 'daily2annual.zoo'         : -) calls to 'as.Date' were changed to 'zoo::as.Date', to avoid possible conflicts with zoo >= 1.7-2
                                       -) default value for 'out.fmt' was changed from "%Y" to "%Y-%m-%d" (this is the default for zoo objects)
        o 'sfreq'                    : -) now gives the correct sampling frequency for zoo objects that are matrix/data.frame
                                       -) now only works with zoo objects (before it also accepted ts objects)
        
        o 'hydroplot'                : -) calls to 'as.Date' were changed to 'zoo::as.Date', to avoid possible conflicts with zoo >= 1.7-2
        o 'monthlyfunction'          : -) calls to 'as.Date' were changed to 'zoo::as.Date', to avoid possible conflicts with zoo >= 1.7-2 
                                          (only for data.frame/matrix objects)
                                       -) fixed bug in the labelling of columns of the output object (only for data.frame/matrix objects)
        o 'hydrokrige'               : -) fixed visualisation error "Error using packet 1. 'breaks' are not unique".
                                       
0.3-4	03-May-2012
        o 'fdc' : new arguments 'leg.cex' and 'leg.pos' to provide better control over the legend
        o 'fdcu': new arguments 'leg.cex' and 'leg.pos' to provide better control over the legend
        
0.3-3	07-Nov-2011
        o new 'fdc.zoo', which works with vectors, matrices and/or data frames
        o 'fdc.matrix'     : -) the flow duration curve of each column is now returned as an output (although not in an efficient way, yet)
          'fdc.data.frame'   -) axis numbers and labels are now drawn only once.
                             -) when missing 'ylim', it is now correctly computed when some series have missing values.
        
0.3-2	15-Sep-2011
        o 'smry' : bugfix in 'smry.zoo' (when some values were NA)
        	
0.3-1	14-Sep-2011
        o hydroTSM 0.3-X is now compatible with R 2.12.X.
          'sp::coordinates' & 'sp::proj4string' were replaced by 'coordinates' & 'proj4string', respectively. Thanks to Uwe Ligges.
        o 'smry' : bugfix in 'smry.data.frame' (when -at least- 1 column was not numeric)

0.3-0	01-Sep-2011

	o hydroTSM now depends on xts >= 0.8-2 (=> zoo >= 1.7-2), in order to make use of improved plotting capabilities for ts objects.
	  The first release of 'xts' after the 0.8-0 (which was set as the default building block for plotting time series in hydroTSM) 
	  was the 0.8-2, and appeared on CRAN on August 9th, 2011	
	o NAMESPACE created, which leads to reduced dependency of packages e1071, gstat, automap, sp
	o 'maptools' package is now "suggested" instead of a dependence. It is only used for reading shapefiles in the 
	  'hydrokrige' and 'mspplot' functions.	
	o 'drawxaxis'       : -) it was re-written, in order to take advantage of some features of the 'xts' 
			         package (now added as a dependence), and now it should work with sub-daily 
			         time series.
			      -) its name was changed from 'drawxaxis' to 'drawTimeAxis', in order to have a 
			         more intuitive name. The old 'drawxaxis' function is deprecated, but 
			         still be kept for back-compatibility reasons.			
	 		      -) 'tick.tstep' and 'lab.tstep' now accept the values: "auto", "quarters", "weeks", "hours", 
	 		         "minutes", and "seconds", and its default value was changed to "auto".
	o 'hydroplot'       : -) it takes advantage of the new 'drawTimeAxis' function.
	  'sname2plot'      : -) now it is able to plot seasonal values (ptype="seasonal")
	                      -) it works with xts objects as well.
			      -) 'tick.tstep' and 'lab.tstep' now accept the values: "auto", "quarters", "weeks", "hours", 
	 		         "minutes", and "seconds", and its default value was changed to "auto". 
	 		      -) the name of 'x' is now used as default for the Y axis label.
	 		      -) an incorrect default title for the daily histogram was fixed.
	 		      -) the default value for 'cex' was changed from 0.7 to 0.3
	 		      -) new arguments: 'from', 'to', for plotting a slice of the original time series
	 		      -) thanks to Tom Elliott for pointing out my attention to this function again !.
	 		      -) new argument: 'h', for plotting horizontal lines in seasonal plots
	 		      -) new argument 'stype', for allowing weather seasons different from 
	                         c("DJF", "MAM", "JJA", "SON") (thanks to Lydie Sichoix !)
	                      -) default value for the 'win.len1' argument was changed from 351*1 to 0, in order to avoid the 
	                         plotting of the 1-year moving average (by default)
	                      -) default value for the 'win.len2' argument was changed from 351*3 to 0, in order to avoid the 
	                         plotting of the 3-years moving average (by default)
	o 'hydroplot'       : -) new argument: 'date.fmt' for being used with the new arguments 'from' and 'to'
	o 'sfreq'           : -) it works now with xts objects
	o 'vector2zoo'      : -) added error checking for length of the numeric vector and the dates.
	o 'hydrokrige'      : -) updated documentation and new example of interpolation over a user-defined raster map.
	o 'monthlyfunction' : -) new 'monthlyfunction.zoo', ~ 8 times faster than before (for data.frames, when out.type="data.frame")
			      -) it works now with matrix objects as well.
	                      -) it works now with xts objects as well.
	o 'annualfunction'  : -) new 'annualfunction.zoo', much faster than before for data.frames.
			      -) it works with matrix objects as well.
	                      -) it works with xts objects as well.
	o 'daily2monthly'   : -) new 'daily2monthly.zoo', much faster than before (for data.frames, when out.type="data.frame")
			      -) it works withannualxts objects as well.	 
	o 'daily2annual'    : -) new 'daily2monthly.zoo', much faster than before (for data.frames, when out.type="data.frame")
			      -) it works with xts objects as well.			                           	
	o 'fdc' and 'fdcu'  : -) new argument 'xat', for setting the position of the 'x' axis labels when 'log="x"'
	o 'time2season'     : -) new argument 'type', for allowing seasons different from 
	                         c("DJF", "MAM", "JJA", "SON") (thanks to Lydie Sichoix !)
	o 'dm2seasonal'     : -) new argument 'out.fmt', for better compatibility with zoo and xts objects.
	                      -) it works with matrix objects as well.
	                      -) it works with xts objects as well.
	                      -) argument 'season' now allows weather seasons typical from 
	                         French Polynesia: c("DJFM", "AM", "JJAS", "ON") (thanks to Lydie Sichoix !)
	o 'seasonalfunction': -) new 'seasonalfunction.zoo', ~ 30 times faster than before (for data.frames, when out.type="data.frame")
			      -) it works with matrix objects as well.
	                      -) it works with xts objects as well.
	                      -) new argument 'type', for allowing weather seasons different from 
	                         c("DJF", "MAM", "JJA", "SON") (thanks to Lydie Sichoix !)	
        o 'extractzoo'      : -) its name was changed from 'extractzoo' to 'extract', in order to have a 
			         shorter name (this function only apply to zoo objects anyway). 
			         The old 'extractzoo' function is deprecated, but still be kept for back-compatibility reasons.			
			      -) new 'extract.zoo'
			      -) argument 'trgt' now allows weather seasons typical from 
	                         French Polynesia: c("DJFM", "AM", "JJAS", "ON") (thanks to Lydie Sichoix !)
	o 'dwi'             : -) new 'dwi.zoo', much faster than before
			      -) it works with xts objects as well.
			      -) fixed documentation of the 'out.unit' argument.
			      -) argument 'tstep' is not required any more, because it is not used any longer.
			         It is kept for backwards compatibility purposes only.
        o 'matrixplot       : -) it works with zoo objects as well (zoo matrices/data.frames)
        o 'izoo2rzoo'       : -) new 'izoo2rzoo.zoo'
                              -) it works with xts objects as well. 
        o 'smry'            : -) new 'smry.zoo'	
                              -) much faster than before for matrices and data.frames 	                            
                              -) it works with xts objects as well. 			      
	o Some 'as.Date' calls were changed to 'zoo::as.Date', in order to work properly with zoo >= 1.7-2
	

0.2-2	14-Apr-2011
	o 'fdc' and 'fdcu': new argument 'yat', for setting the position of the 'y' axis labels  when 'log="y"' (thanks to Santosh Aryal !)
	o All the 'print' calls used to display information messages were replaced by a call to 'message'.
	o SVN started to be used for package development in Rforge (thanks to Simon Urbanek for his great support)
	o Vignette added ('Introductory Analysis of Daily Precipitation Data with hydroTSM')
	o Updated dependence on R >= 2.10.0
	

0.2-1	30-Nov-2010

	o R functions were split up into individual files.
	o 'dip', 'mip', 'yip': added error checking for 'out.type'
	o 'drawxaxis': new argument: lab.fmt, for specifying the format of the axis' labels
	o 'hydroplot', 'sname2plot': removed argument 'sname', and new arguments: 'lab.fmt', 'xlab', 'ylab', 'col', 
	  'cex', 'cex.main', 'cex.axis', 
	  'cex.lab', 'lty', 'lwd', '...'
	o 'sname2ts': new arguments: 'from', 'to', 'date.fmt'
	o 'fdc', 'fdcu': new arguments: 'cex.axis', 'cex.lab'

############
# v 0.2-0: #
############
*) Release Date: 10-Oct-2010

-) Hidden object '.required' was removed from the dataset 'EbroDEM1000m', in order to pass the CRAN tests.

Added functions:
*) 'dwdays'              : Generic function for computing the average amount of dry/wet days by month in a daily time series of precipitation
*) 'fdcu'                : Generic function for plotting flow duration curves with uncertainty bounds.
*) 'daily2monthly.matrix': wrapper to 'daily2monthly.data.frame'
*) 'daily2annual.matrix' : wrapper to 'daily2annual.data.frame'
*) 'fdc.data.frame'      : wrapper to 'fdc.matrix'

Hidden functions:
*) 'dmc'
*) 'drty.dcs2zoo'  
*) 'interpol1'
*) 'infillxy' (ex infill)

Removed functions:
*) plotbands: It was improved and moved to the 'hydroGOF' package, because its functioning is much closer to that package than to this one.

Modified functions:
*) 'sname2ts'                : -) checking for the 'sname' argument was added
*) 'sname2plot'              : -) checking for the 'sname' argument was added
*) 'fdc'                     : -) the default label for each column of the 'x' argument was changed from 'Q1',..., 'Qn' to the original column names in 'x'
                               -) new argument 'lQ.thr', optional for plotting a vertical line in the corresponding threshold for the  probability of excedence corresponding to low flows.
                               -) new argument 'hQ.thr', optional for plotting a vertical line in the corresponding threshold for the  probability of excedence corresponding to high flows.
                               -) new argument 'thr.shw', logical, indicating if the streamflow values corresponding to the user-defined thresholds 'lQ.thr' and 'hQ.thr' have to be 
                                  shown in the plot.
                               -) new argument 'leg.txt', optional, text to be plotted as a legend.
                               -) new argument 'new', logical, indicates if a new graphics device has to be started
                               -) new argument 'log', character, indicates which axis has to be plotted with a logarithmic scale. By default is 'y' 
                               -) new argument 'ylim', numeric, indicates the range of the 'y' axis. It is not needed for only 1 FDC, but is useful when dealing with a 'matrix' or 'data.frame'
*) 'daily2monthly'           : -) new argument 'out.fmt', for selecting if the result will be 'numeric' or 'zoo'. Valid values are: c('numeric', 'zoo') 

*) 'daily2monthly.data.frame': -) fixed bug: when daily data were not present in the original daily ts for one or more entire months it was impossible to obtain the corresponding 
                                  monthly values.
*) 'dailyannual.data.frame'  : -) fixed bug: when daily data were not present in the original daily ts for one or more entire years it was impossible to obtain the corresponding annual values.
*) 'matrixplot'              : -) The argument 'var.type' was removed. The parameter 'ColorRamp' is used instead.
*) 'hydrokrige'              : -) the argument 'IDW.type' was renamed to 'type'
                               -) the argument 'sp.plot' was renamed to 'plot'
                               -) a default value for the argument 'p4s' was added: p4s=CRS(as.character(NA))
                               -) the argument 'date' can be numeric or any string (it is not required anymore to be of 'Date' class), in order to allow to be used with any time step (monthly, half-hourly, etc.), and not only with daily values.
                               -) the argument 'date.fmt' was removed,  
                               -) the argument 'SubCatchments.fname' was renamed to 'subcatchments'
*) 'mspplot'                 : -) the argument 'sp.plot' was renamed to 'plot'
                               -) the argument 'var.type' was removed
                               -) the default value for p4s was set to 'CRS(as.character(NA))'
*) 'matrixplot'              : -) The argument 'var.type' was removed, because it was replaced in behaviour by the 'ColorRamp' argument.
*) 'hydropairs'              : -) The '...' argument was effectively passed to the 'pairs' function.
*) 'hydroplot/sname2plot'    : -) Argument 'win1.len': when a value equal to zero is entered, this moving average is not computed.
                               -) Argument 'win2.len': when a value equal to zero is entered, this moving average is not computed.
                               -) The argument 'elevation' was removed, because it can easily put into the 'main' argument.
*) 'fillin'                  : -) its name was changed to 'infillxy'
*) 'dmc'                     : -) The argument 'target' was changed to 'trgt' (due to 'extractzoo' function) 
*) 'hypsometricc'            : -) Its name was changed to 'hypsometric'
*) 'drawxaxis'               : -) A new argument 'cex.axis' was added, to control the size of the annotations on the axis.


############
# v 0.1.6: #
############
*) Release Date: 30-Nov-2009

Added functions:
*) 'zoo2RHtest': creation of the input file to the 'RHtest_dlyPrcp.r' script that test the homogeneity of climatological time series (http://ccma.seos.uvic.ca)

Modifications:
*) 'hydrokrige': -) The methodology for computing the block averages over the subcatchments was changed, from passing the subcatchments file to the 'autoKrige' or 'idw' function, to use the 'overaly' mehtod with 'fn=mean', because this is the only way to be sure that the 'cellsize'  given by the user is used in the sampling of the subcatchments (the 'sps.arg' argument couldn't be used in the 'idw' function )
                 -) Error checking added when all the measured values are equal, for avoiding the following error:
                     'chfactor.c", line 130: singular matrix in function LDLfactor()'                  
                 -) Added check: the shapefile with the subcatchments must be provided for block interpolations
                 -) Minor bugs corrected when plotting the results of a block interpolation carried out with idw.
*) 'sname2ts'  : -) the 'FUN' argument was removed as requirement when 'tstep.out' is 'daily'
                 -) checking for the 'dates' argument was added
*) 'sname2plot': -) the 'FUN' argument was removed as requirement when 'tstep.out' is 'daily'
                 -) checking for the 'dates' argument was added
*) 'sfreq'     : -) the output of this function were changed to non capital letters ('daily', 'monthly', 'annual'), for an easier link to other functions


############
# v 0.1.5: #
############
*) Release Date: 16-Nov-2009
*) 'hydrokrige': -) Only 'subcatchments' OR 'predictors' field is needed, no both.
                 -) The default value 'NA' for the 'elevation' field was removed
                 -) The default value 'both' for the 'IDW.type' field was changed to 'cells', in case the user does not want the block values over subcatchments.
                 -) The name of the parameter 'var.type' was changed to 'ColorRamp', because it is more intuitive. Its default value was changed from'"Precipitation' to 'PCPAnomaly' because gives a better visual representation, The following possible sets of colours were added: c('PCPAnomaly', 'PCPAnomaly2', 'TEMPAnomaly', 'TEMPAnomaly2', 'TEMPAnomaly3')
                 -) Some bugfixes to the KED wrapper
############
# v 0.1.4: #
############
*) Release Date: 02-Nov-2009
*) 'hydrokrige': 
                 -) it is possible to include the 'idp' (inverse distance power) argument for inverse distance weighted interpolations.
                 -) a checking was added for avoiding that the shapefile with the subcatchments (given by 'subcatchments') and the geographical locations (given by 'x.gis') had different projections, wich prevent the interpolations with 'krige' function.
                 -) the argument 'output.fname' was changed to 'fname'
		 -) Some bugs in the wrapper to the 'autoKrige' function for block values over subcatchments were fixed.
                 -) When 'verbose=TRUE' and 'formula' is provided by the user, information related to the fitted variogram by the 'autoKrige' function is shown.

############
# v 0.1.3: #
############
*) Release Date: 13-Oct-2009
*) New function 'plotbands': Plot a single ts (usually simulated values) and two confidence bands. OPTIONALLY can adds a ts with observed values
*) '.hydroplotts': 2 new argument were added:
                  -) 'tick.tstep': string indicating the time step that have to be used for putting the ticks ont he time axis. 
                                   Possible values are: 'days', 'months', 'years' 
                  -) 'lab.tstep' : string indicating the time step that have to be used for putting the labels ont he time axis. 
                                   Possible values are: 'days', 'months', 'years' 
*) 'hydroplot'   :2 new argument were added:
                  -) 'tick.tstep': string indicating the time step that have to be used for putting the ticks ont he time axis. 
                                   Possible values are: 'days', 'months', 'years' 
                  -) 'lab.tstep' : string indicating the time step that have to be used for putting the labels ont he time axis. 
                                   Possible values are: 'days', 'months', 'years' 
                   A check was added, for detecting when a ts is too short for plotting annual values (length(x) <=366 when 'x' is daily), and the 'tick.tstep' and 'lab.tstep' are automatically changed to 'days' and 'months', respectively. The same checking procedure change 'pfreq' value to skip the annual plots.
*) 'sname2plot'  : 2 new argument were added:
                  -) 'tick.tstep': string indicating the time step that have to be used for putting the ticks on the time axis. 
                                   Possible values are: 'days', 'months', 'years' 
                  -) 'lab.tstep' : string indicating the time step that have to be used for putting the labels on the time axis. 
                                   Possible values are: 'days', 'months', 'years' 
############
# v 0.1.2: #
############
*) Release Date: 01-Oct-2009
*) 'matrixplot': -) a new 'ColorRamp' argument was added, which gives the possibility to the user to pass a personalized color ramp for ploting the maps, with possible values: 
                    c('Precipitation', 'Temperature', 'Days', 'PCPAnomaly', 'TEMPAnomaly', 'TEMPAnomaly2', 'TEMPAnomaly3')
*) 'tsgis2spt' : Additional checking for the input arguments.
*) 'vector2zoo': Small modification for allowing that the 'dates' argument can be any character that can be converted to 'date' class, and not only a 'date' class argument as before.
*) 'mspplot'   : 3 new ColorRamps were added as possible alternatives for the 'ColorRamp' argument: 'PCPAnomaly2', 'TEMPAnomaly2' and 'TEMPAnomaly3'
*) 'tsgis2spt' : its name was changes to 'gists2spt (because it is closer to "spatio-temporal", according to me...)

############
# v 0.1.1: #
############
*) Release Date: 15-Sep-2009
*) 'daily2monthly.data.frame'. Previously, it gave the same result as 'daily2annual.data.frame'. This was corrected.
*) 'daily2monthly.data.frame'. The default argument for 'out.type' was set up to "db", because "data.frame" has no sense here
*) 'monthlytotals.data.frame'. Bug was corrected, because the monthly results were given by row instead of the corresponding column.
*) 'dwiplot'. Its name was changed to 'matrixplot' and a new parameter was added ('var.type') for indicating the color ramp that has to be used depending on the type of variable to be plotted (Days with information, precipitation, temperature)
*) 'dm2seasonal.default'. Checking for missing 'season' argument was added
*) 'dm2seasonal.data.frame'. Checking for missing 'season' argument was added
*) 'mspplot': Two new valid values for the 'var.type' were added: "PCPAnomaly", "TEMPAnomaly", for being used in the plot of anomalies of temperature and precipitation fields. 
              Also, the following parameters were added:
              -)'ColorRamp'   : Gives the possibility to the user to pass a personalized color ramp for plotting the maps
              -)'stations.gis': data.frame with the stations that will be added to the plot. ONLY required when 'stations.plot' == TRUE
              -)'X'           : character, field name in 'x.gis' that stores the easting coordinate of the stations. ONLY required when 'stations.plot' == TRUE
              -)'Y'           : character, field name in 'x.gis' that stores the northing coordinate of the stations. ONLY required when 'stations.plot' == TRUE
*) 'hydroidw': The name of 'N.min', 'N.max' and 'Dist.Max' were changed to 'nmin', 'nmax', 'maxdist', in order to share terminology with the 'krige' function. of the 'gstat' package
               The default value of 'nmin' was cahnged from 1 to 0, for compatibility with the 'krige' function of the 'gstat' package.
               The following parameters were added:
              -)'predictors': OPTIONAL. SpatialGridDataFrame object, with prediction/simulation locations. Usually, a digital elevation model (DEM) read with the 'readGDAL' function of the 'rgdal' package. \cr
              -)'formula'   : Formula to be used in case of ordinary kriging or kriging with external drift. All the variables to be used within 'formula' has to be present both in 'x.gis' and 'predictors'. See the 'formula' argument in '?gstat::krige'. \cr
   

Changed names:
*) 'monthlytotals': Its name was changed to 'monthlyfunction', because now it is possible to apply any R function to summarize the monthly values
*) 'annualmeans'  : Its name was changed to 'annualfunction', because now it is possible to apply any R function to summarize the annual values
*) 'subset.zoo'   : Its name was changed to 'extractzoo', for avoiding conflicts with the default behaviour of the 'subset' function implemented int he zoo package
*) 'hydroidw'     : Its name was changed to 'hydrokrige' due to the addition of OK and KED interpolations through the 'autoKrige' function of the 'automap' package.

Added functions:
-) 'smry'. Computes 13 summary statistics (Min, 1stQ, Mean, Median, 3rdQ, Max, IQR, sd, cv, skewness, kurtosis, amount of elements and amount of NA's) for numerical vector, matrix or data frames.
-) 'seasonaltotals'. Applies any R function to summarize the seasonal values of 'x'
-) 'hypsometricc'. Computes and plots the hypsometric curve corresponding to the elevation values provided by a DEM (read with the 'readGDAL' function)

############
# v 0.1.0: # 
############
-) Release Date: 07-Sep-2009 (but the functions have been developed since 2007)
