NAME

v.circle - Creates a vector file which consists of circle(s) which uses each point in a "site_lists" file as the center of those circle(s).
(GRASS Vector Program)

SYNOPSIS

v.circle
v.circle help
v.circle [ -s] sitefile=name [radius=value] [radius_uom=name] [area=value] [area_uom=name] output=name

DESCRIPTION

"v.circle" will create "polygon" circle(s) around points read from an existing "site_lists" file. The "site_lists" point(s) will be the center(s) for those circle(s) with one circle created per point. The "polygon" circle(s) will be written to a binary vector file. Each "polygon" circle will have 361 points with each point on the circumference of the circle representing 1 degree of arc.

COMMAND LINE OPTIONS

Flags

-s
Automatically run "v.support" on newly created vector file.

Parameters

radius
Radius of circle(s) with "site_lists" point(s) as center(s). If radius selected then area values are not used for computations. If both radius and area selected, then radius has precedence over area.
default: 0.0

radius_uom
Radius unit of measure, ie. (m)meters, ft(feet), (mi)miles.
default: m

area
Area of circle(s) with "site_lists" point(s) as center(s). If area selected then radius values are not used for computations.
default: 0.0

area_uom
Area unit of measure, ie. sqm(square meters), ac(acres), sqmi(square miles), hec(hectares).
default: sqm

sitefile
GRASS site_lists file (input).
output
Vector file to be created (output).

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 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.bubble

AUTHOR

Bruce Powell, National Park Service

Last changed: $Date: 2004/01/29 01:44:15 $