@BeginModule
@NewPage
@Name      = Ensstat
@Title     = Statistical values over an ensemble
@Section   = Statistical values
@Class     = Statistic
@Arguments = ifiles ofile
@Operators = ensmin ensmax enssum ensmean ensavg ensstd ensvar

@BeginDescription
This module computes statistical values over an ensemble of input files.
Depending on the actual operator the minimum, maximum, sum, average
or standard deviation over all input files is written to @file{ofile}. The date 
information for a time step in @file{ofile} is the date of the first input file.
@EndDescription
@EndModule


@BeginOperator_ensmin
@Title     = Ensemble minimum

@BeginDescription
@IfMan
o(t,x) = min{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf min}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator

@BeginOperator_ensmax
@Title     = Ensemble maximum

@BeginDescription
@IfMan
o(t,x) = max{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf max}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginOperator_enssum
@Title     = Ensemble sum

@BeginDescription
@IfMan
o(t,x) = sum{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf sum}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginOperator_ensmean
@Title     = Ensemble mean

@BeginDescription
@IfMan
o(t,x) = mean{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf mean}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginOperator_ensavg
@Title     = Ensemble average

@BeginDescription
@IfMan
o(t,x) = avg{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf avg}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginOperator_ensvar
@Title     = Ensemble variance

@BeginDescription
@IfMan
o(t,x) = var{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf var}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginOperator_ensstd
@Title     = Ensemble standard deviation

@BeginDescription
@IfMan
o(t,x) = std{i1(t,x), i2(t,x), ..., in(t,x)}
@EndifMan
@IfDoc
@BeginMath
o(t,x) = \mbox{\bf std}\{i_1(t,x), i_2(t,x), \cdots, i_n(t,x)\}
@EndMath
@EndifDoc
@EndDescription
@EndOperator


@BeginExample
To compute the ensemble mean over 6 input files, use:
@BeginVerbatim
   cdo ensmean ifile1 ifile2 ifile3 ifile4 ifile5 ifile6 ofile
@EndVerbatim
Or shorter with filename substitution:
@BeginVerbatim
   cdo ensmean ifile[1-6] ofile
@EndVerbatim
@EndExample
