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d.vect.thematic

Displays a thematic vector map in the active graphics frame.

d.vect.thematic [-lnes] map=name [layer=string] column=name [breaks=string [,string,...]] [algorithm=string] [nclasses=integer] colors=string [,string,...] [where=sql_query] [boundary_width=integer] [boundary_color=name] [icon=string] [size=float] [icon_line=string] [icon_area=string] [legend_title=string] [legendfile=name] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

d.vect.thematic map=name column=name algorithm=string colors=string

grass.script.run_command("d.vect.thematic", map, layer="1", column, breaks=None, algorithm=None, nclasses=None, colors, where=None, boundary_width=1, boundary_color="black", icon="basic/x", size=5, icon_line="legend/line", icon_area="legend/area", legend_title=None, legendfile=None, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("d.vect.thematic", map="name", column="name", algorithm="string", colors="string")

Parameters

map=name [required]
    Name of vector map
    Or data source for direct OGR access
layer=string
    Layer number or name
    Layer number. If -1, all layers are displayed.
    Default: 1
column=name [required]
    Name of attribute column to be classified
breaks=string [,string,...]
    Class breaks, without minimum and maximum
algorithm=string
    Algorithm to use for classification
    Allowed values: int, std, qua, equ, dis
    int: simple intervals
    std: standard deviations
    qua: quantiles
    equ: equiprobable (normal distribution)
nclasses=integer
    Number of classes to define
colors=string [,string,...] [required]
    Colors (one per class)
where=sql_query
    WHERE conditions of SQL statement without 'where' keyword
    Example: income < 1000 and population >= 10000
boundary_width=integer
    Boundary width
    Default: 1
boundary_color=name
    Boundary color
    Either a standard color name, R:G:B triplet, or "none"
    Default: black
icon=string
    Point and centroid symbol
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: basic/x
size=float
    Symbol size
    Default: 5
icon_line=string
    Legend symbol for lines
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: legend/line
icon_area=string
    Legend symbol for areas
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: legend/area
legend_title=string
    Thematic map title
legendfile=name
    [DEPRECATED] Output legend file
-l
    Create legend information and send to stdout
-n
    Do not draw map, only output the legend information
-e
    [DEPRECATED] When printing legend info, include extended statistical info from classification algorithm
-s
    Do not show this layer in vector legend

--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

map : str, required
    Name of vector map
    Or data source for direct OGR access
    Used as: input, vector, name
layer : str, optional
    Layer number or name
    Layer number. If -1, all layers are displayed.
    Used as: input, layer
    Default: 1
column : str, required
    Name of attribute column to be classified
    Used as: input, dbcolumn, name
breaks : str | list[str], optional
    Class breaks, without minimum and maximum
algorithm : str, optional
    Algorithm to use for classification
    Allowed values: int, std, qua, equ, dis
    int: simple intervals
    std: standard deviations
    qua: quantiles
    equ: equiprobable (normal distribution)
nclasses : int, optional
    Number of classes to define
colors : str | list[str], required
    Colors (one per class)
    Used as: color
where : str, optional
    WHERE conditions of SQL statement without 'where' keyword
    Example: income < 1000 and population >= 10000
    Used as: input, sql_query, sql_query
boundary_width : int, optional
    Boundary width
    Default: 1
boundary_color : str, optional
    Boundary color
    Either a standard color name, R:G:B triplet, or "none"
    Used as: input, color, name
    Default: black
icon : str, optional
    Point and centroid symbol
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: basic/x
size : float, optional
    Symbol size
    Default: 5
icon_line : str, optional
    Legend symbol for lines
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: legend/line
icon_area : str, optional
    Legend symbol for areas
    Allowed values: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon, basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross, geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle, geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel, geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked, n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6, n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
    Default: legend/area
legend_title : str, optional
    Thematic map title
legendfile : str, optional
    [DEPRECATED] Output legend file
    Used as: output, file, name
flags : str, optional
    Allowed values: l, n, e, s
    l
        Create legend information and send to stdout
    n
        Do not draw map, only output the legend information
    e
        [DEPRECATED] When printing legend info, include extended statistical info from classification algorithm
    s
        Do not show this layer in vector legend

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

d.vect.thematic draws thematic choropleth vector maps based on an attribute column or an expression involving several columns. It takes a list of class breaks (excluding the minimum and maximum values) and a list of colors to apply to the classes (has to be the number of class breaks + 1).

Instead of a list of class breaks, the user can also chose a classification algorithm and a number of classes (nbclasses). See the v.class for more information on these different algorithms.

NOTES

The -l flag instructs the module to print legend information in vector legend format as described in d.legend.vect to standard output for further use in graphical software. When combined with the verbose flag, the legend information will be extended with some additional statistical information. If the -n flag is set, the module will only print the legend information without drawing the map.

Option legendfile, is deprecated, instead use the GRASS_LEGEND_FILE environmental variable (see d.legend.vect) to save legend into a file. Flag -e is deprecated, instead use verbose flag.

EXAMPLES

Thematic map with classes

d.vect.thematic -l map=communes3 column=pop \
  breaks=111393.250000,222785.500000,334177.750000 \
  colors="255:0:0,0:255:0,0:0:255,0,0,0"

Thematic map with calculated class breaks

The following example uses a calculated attribute (density = pop/area) and the standard deviation algorithm to calculate class breaks for 5 classes:

d.vect.thematic -l map=communes2 column=pop/area algorithm=std \
  nbclasses=5 colors="0:0:255,50:100:255,255:100:50,255:0:0,156:0:0"

Thematic map with legend

Example for the North Carolina sample dataset, colorizing basin polygons by average elevation and displaying school capacity:

# create watersheds from elevation map
g.region raster=elevation
r.watershed elevation=elevation threshold=10000 basin=basins_10k

# convert raster to vector
r.to.vect input=basins_10k output=basins_10k type=area column=basin_num

# upload raster statistics to each polygon in vector map
v.rast.stats map=basins_10k raster=elevation column_prefix=elev

# open a graphical display
d.mon wx0

# draw thematic polygons and specify legend title
d.vect.thematic map=basins_10k column=elev_average algorithm=int \
  nclasses=5 colors=0:195:176,39:255:0,251:253:0,242:127:11,193:126:60 \
  legend_title="Average elevation (m)"

# draw thematic points and specify legend title
d.vect.thematic map=schools_wake@PERMANENT column=CORECAPACI algorithm=std \
  nclasses=3 colors=149:203:255,45:143:240,0:81:161 icon=basic/circle size=15 \
  legend_title="School capacity"

# and finally draw legend
d.legend.vect -b at=2,80 font=Sans symbol_size=25

d_vect_thematic example
Thematic map of average elevation and school capacity

SEE ALSO

v.class, d.legend.vect, d.vect, d.graph, v.univar

Check also Python module from AddOns: d.vect.thematic2

AUTHOR

Moritz Lennert

SOURCE CODE

Available at: d.vect.thematic source code (history)
Latest change: Thursday Mar 13 17:53:13 2025 in commit e47ba67