NAME¶
d.thematic.area - Displays a thematic vector area map in the
active frame on the graphics monitor.
KEYWORDS¶
display, cartography
SYNOPSIS¶
d.thematic.area
d.thematic.area help
d.thematic.area [-
len]
map=
name
column=
string [
breaks=
string[,
string,...]]
[
algorithm=
string] [
nbclasses=
integer]
colors=
string[,
string,...] [
layer=
integer]
[
where=
sql_query] [
bwidth=
integer]
[
bcolor=
string] [
render=
string]
[
legendfile=
name] [--
verbose] [--
quiet]
Flags:¶
- -l
-
Create legend information and send to stdout
- -e
-
When printing legend info , include extended statistical info from
classification algorithm
- -n
-
Do not draw map, only output the legend
- --verbose
-
Verbose module output
- --quiet
-
Quiet module output
Parameters:¶
- map=name
-
Name of input vector map
- column=string
-
Data to be classified: column name or expression
- 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)
- nbclasses=integer
-
Number of classes to define
- colors=string[,string,...]
-
Colors (one per class).
- layer=integer
-
Layer number
Layer number. If -1, all layers are displayed.
Default: 1
- where=sql_query
-
WHERE conditions of SQL statement without 'where' keyword
Example: income = 10000
- bwidth=integer
-
Boundary width
Default: 0
- bcolor=string
-
Boundary color
Default: black
- render=string
-
Rendering method for filled polygons
Options: d,c,l
Default: l
d: use the display library basic functions (features: polylines)
c: use the display library clipping functions (features: clipping)
l: use the display library culling functions (features: culling,
polylines)
- legendfile=name
-
File in which to save d.graph instructions for legend display
DESCRIPTION¶
d.thematic.area draws thematic coropleth vector maps based on an
attribute column or an expression involving several columns. It takes a number
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). The
-l flag instructs the module to print legend information (class min |
class max | number of observations in class | color) to standard output for
futher use in graphical software. When given this flag with the
-n
flag, the module will only print the legend information without drawing the
map. One can used
v.class to supply class breaks for d.thematic.area
(see example below);
EXAMPLE¶
d.thematic.area -l map=communes3 data=pop
breaks=111393.250000,222785.500000,334177.750000
colors=255:0:0,0:255:0,0:0:255,0,0,0
The following example uses a calculated attribute (density = pop/area) and
v.class to calculate class breaks and feed them directly into d.thematic.area:
d.thematic.area -l map=communes2 data=pop/area breaks=`v.class -g map=communes2
column=pop/area algo=std nbcla=5`
colors=0:0:255,50:100:255,255:100:50,255:0:0,156:0:0
SEE ALSO¶
v.class d.vect v.univar
AUTHOR¶
Moritz Lennert
Full index
© 2003-2014 GRASS Development Team
