NAME
v.bubble - Creates a vector file which consists of
bubble(s) for each point in a site-file and with a size relative to the z value
of that point.
(GRASS Vector Program)
SYNOPSIS
v.bubble
v.bubble help
v.bubble [ -s] [radius=value]
sitefile=name
output=name field=value
DESCRIPTION
"v.bubble" will create "polygon" circles or bubbles around points read from an
existing
"site_lists" file. The "site_lists" points will be the centers for those
bubbles with one bubble created per point. The size of the bubble is relative to
the z value (or "height" attribute") at that point. The maximum z value
corresponds to a size of "radius".
The "polygon" bubbles will be written to a binary vector file. Each "polygon"
bubble will have 361 points with each point on the circumference of the bubble
representing 1 degree of arc.
COMMAND LINE OPTIONS
Parameters
radius
Maximum radius corresponding with the maximum z value in the "site-file".
One Unit of radius corresponds with one unit of the map.
default: 1.0
sitefile
GRASS site_lists file (input).
output
Vector file to be created (output).
field
Attribute field number to use for operation
The field number specifies the attribute field in sites list (point map)
which shall be used. This is useful in case of multiple attribute
sites maps.
Flags
-s
Automatically run "v.support" on newly created vector file.
NOTES
The programm is based on v.circle
BUGS
Due to the limitations of the vector engine in versions of GRASS prior to 5.7,
display of overlapping circles may not work correctly. You have two options:
a) make your radius smaller.
b) Install GRASS 5.7 or newer and use either v.buffer and v.patch
in a loop or d.vect.chart ctype=pie with one data column. Sorry for the
inconvenience.
SEE ALSO
v.circle
AUTHOR
Job Spijker (spijker@geo.uu.nl) , Utrecht University/Department of Geochemistry
Last changed: $Date$