wgrib2: -precision
Precision
Except for grid values stored in IEEE format, grid values are
stored with user-defined precision. By having a variable precision,
the space required can be reduced. For having the temperature
stored to a thousandth of a degree would be wasteful as thermometers
typically give a result to a tenth of a degree.
Grid point values are stored as scaled integers, the scaling
determines the precision.
val = (base+i*2^bin_scaling)*10^dec_scaling
base = real*4
bin_scaling = integer from -127 .. 127
dec_scaling = integer from -127 .. 127
The -precision option prints the bin_scaling
and dec_scaling values.
The -precision output can be read by
-set_metadata and
-set_metadata_str options to set the precision.
Usage
-precision
Examples
$ wgrib2 ecmwf.tp.hc -precision
1:0:encode i*2^-4*10^0
$ wgrib2 wind.grb -precision
1:0:encode i*2^0*10^-1
2:97922:encode i*2^0*10^-1
3:179554:encode i*2^0*10^-1
See also:
-packing,
-scale,
-set_bin_prec,
-set_metadata,
-set_metadata_str,
-set_scale,
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