d.vect.thematic(1grass) GRASS GIS User's Manual d.vect.thematic(1grass)
NAME
d.vect.thematic - Displays a thematic vector map in the active graph-
ics frame.
KEYWORDS
display, cartography, choropleth map, legend
SYNOPSIS
d.vect.thematic
d.vect.thematic --help
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=inte-
ger] [boundary_color=name] [icon=string] [size=float]
[icon_line=string] [icon_area=string] [legend_title=string] [leg-
endfile=name] [--overwrite] [--help] [--verbose] [--quiet] [--ui]
Flags:
-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 statisti-
cal 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
--ui
Force launching GUI dialog
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
Options: 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
Options: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, ba-
sic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3,
basic/diamond, basic/hexagon, basic/marker, basic/octagon, ba-
sic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, ba-
sic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star,
extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, ex-
tra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, ex-
tra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw,
extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, ex-
tra/ring, extra/simple_zia, extra/target, geology/circle_cross, ge-
ology/half-arrow_left, geology/half-arrow_right, geol-
ogy/strike_box, geology/strike_circle, geology/strike_cleavage, ge-
ology/strike_half-bowtie, geology/strike_line, geology/strike_par-
allel, geology/strike_triangle, legend/area, legend/area_curved,
legend/line, legend/line_crooked, n_arrows/basic_compass, n_ar-
rows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_ar-
rows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_ar-
row5, 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
Options: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, ba-
sic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3,
basic/diamond, basic/hexagon, basic/marker, basic/octagon, ba-
sic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, ba-
sic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star,
extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, ex-
tra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, ex-
tra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw,
extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, ex-
tra/ring, extra/simple_zia, extra/target, geology/circle_cross, ge-
ology/half-arrow_left, geology/half-arrow_right, geol-
ogy/strike_box, geology/strike_circle, geology/strike_cleavage, ge-
ology/strike_half-bowtie, geology/strike_line, geology/strike_par-
allel, geology/strike_triangle, legend/area, legend/area_curved,
legend/line, legend/line_crooked, n_arrows/basic_compass, n_ar-
rows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_ar-
rows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_ar-
row5, 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
Options: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, ba-
sic/box, basic/circle, basic/cross1, basic/cross2, basic/cross3,
basic/diamond, basic/hexagon, basic/marker, basic/octagon, ba-
sic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, ba-
sic/triangle, basic/x, demo/muchomurka, demo/smrk, extra/4pt_star,
extra/adcp, extra/airport, extra/alpha_flag, extra/bridge, ex-
tra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, ex-
tra/half-box, extra/half-circle, extra/offbox_ne, extra/offbox_nw,
extra/offbox_se, extra/offbox_sw, extra/pentagon, extra/ping, ex-
tra/ring, extra/simple_zia, extra/target, geology/circle_cross, ge-
ology/half-arrow_left, geology/half-arrow_right, geol-
ogy/strike_box, geology/strike_circle, geology/strike_cleavage, ge-
ology/strike_half-bowtie, geology/strike_line, geology/strike_par-
allel, geology/strike_triangle, legend/area, legend/area_curved,
legend/line, legend/line_crooked, n_arrows/basic_compass, n_ar-
rows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b, n_ar-
rows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_ar-
row5, 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
DESCRIPTION
d.vect.thematic draws thematic choropleth vector maps based on an at-
tribute 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 classifi-
cation 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 fur-
ther use in graphical software. When combined with the verbose flag,
the legend information will be extended with some additional statisti-
cal 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 en-
vironmental 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 poly-
gons 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
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)
Accessed: unknown
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GRASS 7.8.7 d.vect.thematic(1grass)
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