.TH r.describe 1grass "" "GRASS 8.3.1" "GRASS GIS User's Manual"
.SH NAME
\fI\fBr.describe\fR\fR  \- Prints terse list of category values found in a raster map layer.
.SH KEYWORDS
raster, metadata
.SH SYNOPSIS
\fBr.describe\fR
.br
\fBr.describe \-\-help\fR
.br
\fBr.describe\fR [\-\fB1rndi\fR] \fBmap\fR=\fIname\fR  [\fBnull_value\fR=\fIstring\fR]   [\fBnsteps\fR=\fIinteger\fR]   [\-\-\fBhelp\fR]  [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR]  [\-\-\fBui\fR]
.SS Flags:
.IP "\fB\-1\fR" 4m
.br
Print the output one value per line
.IP "\fB\-r\fR" 4m
.br
Only print the range of the data
.IP "\fB\-n\fR" 4m
.br
Suppress reporting of any NULLs
.IP "\fB\-d\fR" 4m
.br
Use the current region
.IP "\fB\-i\fR" 4m
.br
Read floating\-point map as integer
.IP "\fB\-\-help\fR" 4m
.br
Print usage summary
.IP "\fB\-\-verbose\fR" 4m
.br
Verbose module output
.IP "\fB\-\-quiet\fR" 4m
.br
Quiet module output
.IP "\fB\-\-ui\fR" 4m
.br
Force launching GUI dialog
.SS Parameters:
.IP "\fBmap\fR=\fIname\fR \fB[required]\fR" 4m
.br
Name of raster map
.IP "\fBnull_value\fR=\fIstring\fR" 4m
.br
String representing NULL value
.br
Default: \fI*\fR
.IP "\fBnsteps\fR=\fIinteger\fR" 4m
.br
Number of quantization steps
.br
Default: \fI255\fR
.SH DESCRIPTION
\fI\fBr.describe\fR\fR prints a terse listing of category values found in
a user\-specified raster map layer.
.PP
\fI\fBr.describe\fR\fR 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 \fIreclassify\fR or \fIrescale\fR the data,
since these functions (\fIr.reclass\fR and
\fIr.rescale\fR)
also ignore the current \fIgeographic region\fR
and \fImask\fR.
.PP
The \fI\fBnv\fR\fR parameter sets the string to be used to represent NULL
values in the module output; the default is \(cq*\(cq.
.PP
The \fI\fBnsteps\fR\fR parameter sets the number of quantisation steps to divide into
the input raster map.
.SH NOTES
.SS FLAGS
If the user selects the \fB\-r\fR 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).
.PP
The \fB\-d\fR flag can be used to force \fIr.describe\fR 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.
.PP
If the \fB\-1\fR flag is specified, the output appears with one category value/range per line.
.PP
The \fB\-n\fR flag suppresses the reporting of NULL values.
.SH EXAMPLES
The following examples are from the Spearfish60 sample Location:
.PP
# Print the full list of raster map categories:
.br
.nf
\fC
r.describe landcover.30m
* 11 21\-23 31 32 41\-43 51 71 81\-83 85 91 92
\fR
.fi
.PP
# Print the raster range only:
.br
.nf
\fC
r.describe \-r landcover.30m
11 thru 92
*
\fR
.fi
# Print raster map category range, suppressing nulls:
.br
.nf
\fC
r.describe \-n landcover.30m
11 21\-23 31 32 41\-43 51 71 81\-83 85 91 92
\fR
.fi
.PP
# Print raster map categories, one category per line:
.br
.nf
\fC
r.describe \-1 geology
*
1
2
3
4
5
6
7
8
9
\fR
.fi
.PP
.SH SEE ALSO
\fI
g.region,
r.mask,
r.reclass,
r.report,
r.rescale,
r.stats,
r.univar
\fR
.SH AUTHOR
Michael Shapiro, U.S. Army Construction Engineering Research Laboratory
.SH SOURCE CODE
.PP
Available at:
r.describe source code
(history)
.PP
Accessed: Sunday Dec 17 17:21:44 2023
.PP
Main index |
Raster index |
Topics index |
Keywords index |
Graphical index |
Full index
.PP
© 2003\-2023
GRASS Development Team,
GRASS GIS 8.3.1 Reference Manual