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NAME

r.stats.quantile - Compute category quantiles using two passes.

KEYWORDS

raster, statistics, percentile, quantile

SYNOPSIS

r.stats.quantile
r.stats.quantile --help
r.stats.quantile [-rpt] base=name cover=name [quantiles=integer] [percentiles=float[,float,...]] [bins=integer] [output=name[,name,...]] [file=name] [separator=character] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-r
Create reclass map with statistics as category labels
-p
Do not create output maps; just print statistics
-t
Print statistics in table format
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

base=name [required]
Name of base raster map
cover=name [required]
Name of cover raster map
quantiles=integer
Number of quantiles
percentiles=float[,float,...]
List of percentiles
Default: 50
bins=integer
Number of bins to use
Default: 1000
output=name[,name,...]
Resultant raster map(s)
file=name
Name for output file (if omitted or "-" output to stdout)
separator=character
Field separator
Special characters: pipe, comma, space, tab, newline
Default: :

Table of contents

DESCRIPTION

r.stats.quantile is a tool to analyse exploratory statistics of a floating-point "cover layer" according to how it intersects with objects in a "base layer". It provides quantile calculations as selected "zonal statistics".

NOTES

r.stats.quantile is intended to be a partial replacement for r.statistics, with support for floating-point cover maps. It provides quantile calculations, which are absent from r.stats.zonal.

EXAMPLE

In this example, the raster polygon map zipcodes in the North Carolina sample dataset is used to calculate quantile raster statistics using the elevation raster map:
g.region raster=zipcodes -p

# print quantiles
r.stats.quantile base=zipcodes cover=elevation quantiles=3 -p
27511:0:33.333333:134.717392
27511:1:66.666667:143.985723
27513:0:33.333333:140.669993
27513:1:66.666667:146.279449
27518:0:33.333333:115.140101
27518:1:66.666667:129.893723
[...]

# write out percentile raster maps
r.stats.quantile base=zipcodes cover=elevation percentiles=25,50,75 \
  output=zipcodes_elev_q25,zipcodes_elev_q50,zipcodes_elev_q75

SEE ALSO

r.quantile, r.stats.zonal, r.statistics

AUTHOR

Glynn Clements
Markus Metz

Last changed: $Date: 2017-05-07 13:27:56 -0700 (Sun, 07 May 2017) $

SOURCE CODE

Available at: r.stats.quantile source code (history)


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