NAME

       r.describe  - Prints terse list of category values found in a raster map layer.

KEYWORDS

       raster, metadata

SYNOPSIS

       r.describe
       r.describe --help
       r.describe    [-1rndi]   map=name    [null_value=string]     [nsteps=integer]     [--help]
       [--verbose]  [--quiet]  [--ui]

   Flags:
       -1
           Print the output one value per line

       -r
           Only print the range of the data

       -n
           Suppress reporting of any NULLs

       -d
           Use the current region

       -i
           Read floating-point map as integer

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       map=name [required]
           Name of raster map

       null_value=string
           String representing NULL value
           Default: *

       nsteps=integer
           Number of quantization steps
           Default: 255

DESCRIPTION

       r.describe prints a terse listing of category values found in a user-specified raster  map
       layer.

       r.describe  ignores  the  current geographic region and mask, and reads the full extent of
       the input raster map.  This functionality is useful if the user intends to  reclassify  or
       rescale  the data, since these functions (r.reclass and r.rescale) also ignore the current
       geographic region and mask.

       The nv parameter sets the string to be used to represent NULL values in the module output;
       the default is ’*’.

       The nsteps parameter sets the number of quantisation steps to divide into the input raster
       map.

NOTES

   FLAGS
       If the user selects the -r flag, a range of category values found in the raster map  layer
       will  be printed. The range is divided into three groups: negative, positive, and zero. If
       negative values occur, the minimum  and  maximum  negative  values  will  be  printed.  If
       positive  values  occur,  the minimum and maximum positive values will be printed. If zero
       occurs, this will be indicated. The range report will generally run faster than  the  full
       list (the default output).

       The  -d  flag  can  be used to force r.describe to respect the current region extents when
       repoting raster map categories. The default behavior is to read the  full  extent  of  the
       input raster map.

       If the -1 flag is specified, the output appears with one category value/range per line.

       The -n flag suppresses the reporting of NULL values.

EXAMPLES

       The following examples are from the Spearfish60 sample Location:

       # Print the full list of raster map categories:
       r.describe landcover.30m
       * 11 21-23 31 32 41-43 51 71 81-83 85 91 92

       # Print the raster range only:
       r.describe -r landcover.30m
       11 thru 92
       *
       # Print raster map category range, suppressing nulls:
       r.describe -n landcover.30m
       11 21-23 31 32 41-43 51 71 81-83 85 91 92

       # Print raster map categories, one category per line:
       r.describe -1 geology
       *
       1
       2
       3
       4
       5
       6
       7
       8
       9

SEE ALSO

        g.region, r.mask, r.reclass, r.report, r.rescale, r.stats, r.univar

AUTHOR

       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory

SOURCE CODE

       Available at: r.describe source code (history)

       Main index | Raster index | Topics index | Keywords index | Graphical index | Full index

       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual