A new processing element has been added: HNW_DISTRIBUTE. This distributes accumulated precipitation over a number of preceeding time steps. This is useful, for example, when one has an hourly file that contains 24 hours sums of precipitation, written as nodata for all time steps and the accumulation on the last time step of the 24 hours period. Since this is implemented as a filter, it is then possible to also add an undercatch correction (and don't forget to re-accumulate anyway in the resampling methods!).

GeotopIO: Geotop deals with air pressure in mbar, thus the convertUnits and convertUnitsBack functions needed to be adapted.

A little more cleanup (constification, mostly) in GSNIO as well as documentation. Updated the example io.ini. And a new data generator: Brutsaert for clear sky ILWR.

Small cleanup in GSNIO, changing URL/USER/PASS to GSN_URL/GSN_USER/GSN_PASS. Updated the documentation version; fixed a documentation bug.

Using the new Coords constructor and making the list of STATIONS in GRIBIO support discontinuous numbering

A new concept has been introduced: virtual stations. These are points where the meteo data will be transparently spatially interpolated and returned to getMeteoData calls. This allows a point model like Snowpack to work on virtual stations without any internal changes. A few new keys have been introduced in order to provide the necessary information: virtual stations location, meteo parameters to interpolate. For example:
VIRTUAL_STATIONS = true
VIRTUAL_PARAMETERS = TA RH HNW HS VW RSWR ILWR
VSTATION1 = 46.8 9.833333
VSTATION2 = 46.7 9.9

A few drawbacks still exist: the time range getMeteoData call is not supported yet. A DEM must be provided (ie DEM key in ini file). Obviously, all interpolated parameters must have been associated with interpolation algorithms. The virtual stations have IDs such as VIR1, VIR2, etc For performance reasons, the interpolation is then performed on a one cell dem, which means that algorithms using dem characteristics would (currently) be messed up. Basically, this is still a work in progress before everything is robust!

Otherwise, some POPC ifdef have been removed and the "iomanager.interpolate(... Grid2DObject)" call has been removed since the "iomanager.getMeteoData(... Grid2DObject)" call should be used instead (for consistency).

Removing an unnecessary vector copying in BufferedIOHandler. A new private method has been added that IOManager can call.

In order to be able to read arc grids produced by R, the headers are now read in a case insensitive manner

speeding up IOUtils convertString<double>: Adding an explicit implementation for the conversion of strings to doubles, based on strtod from the cstdlib. This function cuts the runtime of this function to about a third.

libsmet: a new convert_to_double implementation, based on strtod from the cstdlib, cuts conversion time to about a fourth of the stringstream implementation.

GSNIO: Missing NULL values and missing fields and units keys in the header have been fixed on the GSN server side. Plugin updated accordingly.

GSNIO: Now we can deal with offsets and multipliers, which are sometimes indicated in a UTF8 string after the fields definition in the header. The units are given as "°C" or "%" for instance. Thus we can perform a calculation to MKSA. 

GSNIO: Cosmetic adjustments. If the user requested station does not exist, there will be an exception thrown. Otherwise the most pressing issue remains the NULL values in GSN.

GSNIO: reading of meteo data works now. However there are the usual GSN issues, which are plentiful and painful:
1) Big problem: NULL values seem to actually come as 0 values
2) parameter naming conventions: totally inconsistent, also one station might have more than one sensor for a parameter, which one to use?
3) Slow, impossible to retrieve meta data for one station only, meta data formatted in obscure way -> necessary to guess where the timestamp is (current guess position 1 or 2 in the csv formatted data row).

GSNIO: reading of StationData now works perfectly,although terribly slow, due to the fact that it is not possible to retrieve meta data for a selected number of stations only.

The LIDW_LAPSE method is now back. It still works the same, ie it can produce very unatural results depending on the stations set that is used!

Deleting old GSNIO plugin based on SOAP messages and adding new framework based on REST API and libcurl (gnutls variant).

The version number has been changed to 2.4.1 (this will most probably be an internal release shipped with Snowpack).

Bringing back the LIDW spatial interpolation method that perfoms IDW on a subset of the stations. At least it compiles...