DESCRIPTION
d.vect.chart displays charts for GRASS vector data in the active
frame on the graphics monitor.
NOTES
The charts are positioned as follows:
- vector points: on point position,
- vector lines: on line centers,
- vector areas: on area centroids.
Bar charts are placed with their lower edge starting from the y-coordinate
of the feature being symbolized, and centered with respect to the x-coordinate.
The -c flag can be used to center the bar chart in both x and y
directions.
The 'sizecol' parameter is proportionate to the radius.
The optional max_ref parameter accepts a list of values that
represent the maximum value for each column listed in the values for the
parameter columns. These values are used to create a framed bar
plot if chart_type is bar (See Example 2).
EXAMPLES
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)
SEE ALSO
d.erase,
d.vect,
d.vect.thematic,
d.what.vect,
d.rast
AUTHOR
Radim Blazek, ITC-Irst, Trento, Italy
Last changed: $Date$