Flags:

-c

Center the bar chart around a data point

-l

Create legend information and send to stdout

-3

Create 3D charts

--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

type=string[,string,...]

Input feature type
Options: point, line, boundary, centroid, area
Default: point,line,boundary,centroid

layer=string

Layer number or name
Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
Default: 1

chart_type=string

Chart type
Options: pie, bar
Default: pie

columns=name[,name,...] [required]

Attribute columns containing data

size_column=name

Column used for pie chart size

size=integer

Size of chart (diameter for pie, total width for bar)
Default: 40

scale=float

Scale for size (to get size in pixels)
Default: 1

outline_color=name

Outline color
Either a standard color name or R:G:B triplet
Default: black

colors=name[,name,...]

Colors used to fill charts
Either a standard color name or R:G:B triplet
Default: black

max_ref=float[,float,...]

Maximum value used for bar plot reference

Example 1

Pie-charts of monthly winter precipitation (North Carolina sample dataset):

g.region vector=nc_state -p
d.vect nc_state
d.vect.chart precip_30ynormals chart_type=pie columns=nov,dec,jan,feb -l
# show pie chart as 3D
d.erase
d.vect nc_state
d.vect.chart precip_30ynormals chart_type=pie columns=nov,dec,jan,feb -l -3

2D pie-chart of monthly winter precipitation in North Carolina

3D pie-chart of monthly winter precipitation in North Carolina

Example 2

Bar-chart of different census map values:

d.vect.chart map=vectmap columns=cens51,cens61,cens71,cens81 chart_type=bar

Example 3

Creation of framed bar charts of an erodibiliy index from the Spearfish sample dataset:

g.region raster=erode.index -p
r.to.vect -s input=erode.index output=erode_index type=area
v.extract input=erode_index output=erode_index_ctrds type=centroid
d.rast aspect
d.vect.chart map=erode_index_ctrds chart_type=bar columns=cat \
             size=10 max_ref=12 scale=0.05 colors=yellow
d.vect erode_index_ctrds icon=basic/circle fcol=black col=black size=5

Bar charts of an erodibiliy index (spatial subset)