@BeginModule
@NewPage
@Name      = Zonstat
@Title     = Zonal statistical values
@Section   = Statistical values
@Class     = Statistic
@Arguments = ifile ofile
@Operators = zonmin zonmax zonsum zonmean zonavg zonstd zonvar

@BeginDescription
This module computes zonal statistical values of the input fields.
According to the actual operator the zonal minimum, maximum, 
sum, average, standard deviation or variance is written to @file{ofile}.
All input fields must have the same rectangular grid. 
@EndDescription
@EndModule


@BeginOperator_zonmin
@Title     = Zonal minimum

@BeginDescription
For every latitude the minimum over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonmax
@Title     = Zonal maximum

@BeginDescription
For every latitude the maximum over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonsum
@Title     = Zonal sum

@BeginDescription
For every latitude the sum over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonmean
@Title     = Zonal mean

@BeginDescription
For every latitude the mean over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonavg
@Title     = Zonal average

@BeginDescription
For every latitude the average over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonvar
@Title     = Zonal variance

@BeginDescription
For every latitude the variance over all longitudes is computed.
@EndDescription
@EndOperator


@BeginOperator_zonstd
@Title     = Zonal standard deviation

@BeginDescription
For every latitude the standard deviation over all longitudes is computed.
@EndDescription
@EndOperator


@BeginExample
To compute the zonal mean of all input fields, use:
@BeginVerbatim
   cdo zonmean ifile ofile
@EndVerbatim
@EndExample
