r.quantile.ref

Determines quantile for input value from reference raster map layers.

r.quantile.ref [-z] input=name [reference=name [,name,...]] [file=name] output=name [range=lo,hi] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

r.quantile.ref input=name output=name

grass.script.run_command("r.quantile.ref", input, reference=None, file=None, output, range=None, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("r.quantile.ref", input="name", output="name")

Parameters

Command linePython (grass.script)

input=name [required]
    Name of input raster map
reference=name [,name,...]
    List ofreference raster maps
file=name
    Input file with one reference raster map name per line
output=name [required]
    Name for output raster map
range=lo,hi
    Ignore values outside this range
-z
    Do not keep files open
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

input : str, required
    Name of input raster map
    Used as: input, raster, name
reference : str | list[str], optional
    List ofreference raster maps
    Used as: input, raster, name
file : str, optional
    Input file with one reference raster map name per line
    Used as: input, file, name
output : str, required
    Name for output raster map
    Used as: output, raster, name
range : tuple[float, float] | list[float] | str, optional
    Ignore values outside this range
    Used as: lo,hi
flags : str, optional
    Allowed values: z
    z
        Do not keep files open
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

r.quantile.ref computes for each pixel the quantile ranking of the input value against the reference maps: values of 0, 0.5 and 1.0 respectively indicate that the input value corresponds with the minimum, median or maximum of the reference values. A value of -1 is assigned if the input value is smaller than the minimum and a value of 2 is assigned if the input value is larger than the maximum.

r.quantile.ref can be regarded as the inverse of r.series method=quantile: while r.series calculates the value for a given quantile, r.quantile.ref calculates the quantile for a given value. This is useful to compare e.g. current environmental conditions to a time series of historical environmental conditions.

EXAMPLE

Create some reference rasters:

r.mapcalc "ref1 = 1"
r.mapcalc "ref2 = 2"
r.mapcalc "ref3 = 3"
r.mapcalc "ref4 = 5"
r.mapcalc "ref5 = 5"
r.mapcalc "ref6 = 5"

Create a test raster with cell value 4.5:

r.mapcalc "test = 4.5"

Get the quantile of the test raster for the reference maps:

r.quantile.ref input=test reference=ref1,ref2,ref3,ref4,ref5,ref6 output=test_quant

The quantile corresponding to the value 4.5 is 0.55. Create a test raster with cell value 5:

r.mapcalc "test = 5"

Get the quantile of the test raster for the reference maps:

r.quantile.ref input=test reference=ref1,ref2,ref3,ref4,ref5,ref6 output=test_quant

The quantile corresponding to the value 5 is 0.8.

AUTHOR

Markus Metz

SOURCE CODE

Available at: r.quantile.ref source code (history)
Latest change: Thursday Feb 20 13:02:26 2025 in commit 53de819