@BeginModule
@NewPage
@Name      = EcaEtr
@Title     = Intra-period extreme temperature range
@Section   = ECA indices
@Class     = ECA index
@Arguments = ifile1 ifile2 ofile
@Operators = eca_etr

@BeginDescription
Let @file{ifile1} and @{ifile2} be time series of maximum and minimum
temperatures TX and TN, respectively. Then the extreme temperature
range is the difference of the maximum of TX and the minimum of TN.
Note that TX and TN must be given in the same units.
The date information for a time step in @file{ofile} is the date of
the last contributing time steps in @file{ifile1} and @file{ifile2}.
@EndDescription
@EndModule


@BeginOperator_eca_etr
@Title     = Intra-period extreme temperature range
@EndOperator


@BeginExample
To get the intra-period extreme temperature range for two time
series of maximum and minimum temperatures, use:
@BeginVerbatim
   cdo eca_etr txfile tnfile ofile
@EndVerbatim
@EndExample
