This module contains functions to add new variables to a
variable list and to get information about variables from
a variable list. To add new variables to a variables list
one of the following timestep types must be specified:

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\hspace*{8mm}\begin{minipage}{15cm}
\begin{deflist}{{\large\tt TSTEP\_CONSTANT \ \ }}
\item[{\large\tt TSTEP\_CONSTANT }]  The data values have no time dimension.
\item[{\large\tt TSTEP\_INSTANT }]  The data values are representative of points in space or time (instantaneous).
\item[{\large\tt TSTEP\_ACCUM }]  The data values are representative of a sum or accumulation over the cell.
\item[{\large\tt TSTEP\_AVG }]  Mean (average value)  
\item[{\large\tt TSTEP\_MAX }]  Maximum  
\item[{\large\tt TSTEP\_MIN }]  Minimum
\item[{\large\tt TSTEP\_SD }]  Standard deviation
\end{deflist}
\end{minipage}
\vspace*{3mm}

The default data type is 16 bit for GRIB and 32 bit for all other file
format types. To change the data type use one of the following 
predefined constants:

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\begin{deflist}{{\large\tt DATATYPE\_PACK1 \ \ }}
\item[{\large\tt DATATYPE\_PACK8}]    8 packed bit (only for GRIB)
\item[{\large\tt DATATYPE\_PACK16}]  16 packed bit (only for GRIB)
\item[{\large\tt DATATYPE\_PACK24}]  24 packed bit (only for GRIB)
\item[{\large\tt DATATYPE\_FLT32}]   32 bit floating point
\item[{\large\tt DATATYPE\_FLT64}]   64 bit floating point
\item[{\large\tt DATATYPE\_INT8}]     8 bit integer
\item[{\large\tt DATATYPE\_INT16}]   16 bit integer
\item[{\large\tt DATATYPE\_INT32}]   32 bit integer
\end{deflist}
\end{minipage}
%\vspace*{3mm}
%
%To define attributes, one of the following data types must be use:
%
%\vspace*{3mm}
%\hspace*{8mm}\begin{minipage}{15cm}
%\begin{deflist}{{\large\tt DATATYPE\_TXT \ \ }}
%\item[{\large\tt DATATYPE\_TXT}]   Text
%\item[{\large\tt DATATYPE\_INT}]   Integer
%\item[{\large\tt DATATYPE\_FLT}]   Floating point
%\end{deflist}
%\end{minipage}

