[[Image(Rlogo.jpg)]]

  * [wiki:./versions Versions]
  * [wiki:./prerequisites Pre-requisites]
  * [wiki:./Authentication Authentication]
  * [wiki:./Homogeneization Data Homogeneization]
  * [wiki:./Examples Examples]

= Overview of the `ecomsUDG.Raccess` package  

Since the [http://www.r-project.org/ R language] has been adopted for some key tasks in the EUPORIAS and SPECS projects (including the development of comprehensive validation and statistical-downscaling packages), the `ecomsUDG.Raccess` is envisaged as a user-friendly, R-based interface to the ECOMS User Data Gateway, enabling [wiki:./Authentication authentication] and remote access to the different datasets (seasonal forecasting, observations, reanalysis) currently available. Moreover, `ecomsUDG.Raccess` implements data homogenization (a single vocabulary) and time filtering/aggregation functionality.

The `ecomsUDG.Raccess` package relies on the `rJava` package as an interface to the powerful capabilities of the [http://www.unidata.ucar.edu/downloads/netcdf/netcdf-java-4/index.jsp Unidata's netCDF Java library].

{{{#!comment
  * [wiki:./Functions Defined Functions]
 }}}

The following panels show an illustrative use of ECOMS-UDG to obtain the minimum DJF temperature DJF bias for System4 hindcast (one-month lead time) over Europe. WFDEI is used as reference.
||= R code =||= Output =||
{{{#!td
   {{{
obs <- loadECOMS(dataset = "WFDEI", 
                  var = "tasmin",
                  season = c(12,1,2))
prd<- loadECOMS(dataset = ”System4_seasonal_15", 
                  var = "tasmin”, 
                  season = c(12,1,2), 
                  members = 1:2, 
                  leadMonth = 1)
  }}}
  {{{
obsr <- interpGridData(gridData = obs, 
                  new.grid = getGrid(prd), 
                  method = "bilinear")
plotMeanBias(obsr,prd)
  }}}
}}}
{{{#!td
[[Image(fig_bias.png)]]
}}}