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HOME > Monitoring_and_Data > Oceanic and Atmospheric Data > Reanalysis: Atmospheric Data > wgrib2-scale
 

wgrib2: -scale

Introduction

In grib, grid values are usually stored as

  grid_value = (ref_value + I*2**bin_scaling)) * 10**decimal_scaling.
    ref_value = 32-bit IEEE floating point number
    I is a positive integer
    binary_scaling = -127..127
    decimal_scaling = -127..127
This is not an absolute as the grid point values can be stored as a spectral coefficients, IEEE floating point values and other formats. The -scale option prints the binary and scaling factors.

Usage

-scale

Example

bash-4.1$ wgrib2 gep19.t00z.pgrb2af180  -scale -for 13:14
13:473374:scale=-3,4
14:528630:scale=-1,0
bash-4.1$ wgrib2 gep19.t00z.pgrb2af180  -scale -for 13:14 -v -packing
13:473374:scale=-3,4:packing=grid point data - jpeg2000 compression,j val=(2.32109e+06+i*2^4)*10^-3, i=0..65535 (#bits=16)
14:528630:scale=-1,0:packing=grid point data - jpeg2000 compression,j val=(2215+i*2^0)*10^-1, i=0..1023 (#bits=10)

See also: -scaling -set_scaling


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Page last modified: Dec 21, 2015
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