r.circle(1)		      Grass User's Manual		   r.circle(1)



NNAAMMEE
       rr..cciirrccllee  -  Creates  a raster map containing concentric rings around a
       given point.

SSYYNNOOPPSSIISS
       rr..cciirrccllee  [[--bb]]  oouuttppuutt==_n_a_m_e  ccoooorrddiinnaattee==_x_,_y   [mmiinn==_v_a_l_u_e]   [mmaaxx==_v_a_l_u_e]
       [mmuulltt==_v_a_l_u_e]

DDEESSCCRRIIPPTTIIOONN
       This  module  creates a raster map containing concentric rings around a
       given point.  The cell values are increasing  linear  from  the	center
       point  to  outer  rings.  Minimum  and  maximum radius can be selected.
       Optionally a "donut" ring can be created to use as (binary) filter  for
       _i_._i_f_f_t inverse Fourier transform (apply filter with _r_._m_a_s_k).

OOPPTTIIOONNSS
   FFllaagg::
       --bb     Generate binary raster map


   PPaarraammeetteerrss::
       oouuttppuutt==_n_a_m_e
	      Name for new raster file

       ccoooorrddiinnaattee==_x_,_y
	      The coordinate of the center (easting, northing)

       mmiinn==_v_a_l_u_e
	      Minimum radius for ring/circle map (in cell units)

       mmaaxx==_v_a_l_u_e
	      Maximum radius for ring/circle map (in cell units)

       mmuulltt==_v_a_l_u_e
	      Multiplier


EEXXAAMMPPLLEESS
       Generate a circle at current map center with a radius of 300m:

	     EASTCENTER=`g.region -c |	awk ' /region center easting:/ { print
       $4 }'`
	     NORTHCENTER=`g.region -c | awk  '	/region  center  northing:/  {
       print $4 }'`
	     r.circle	 -b   out=circle   coordinate=$EASTCENTER,$NORTHCENTER
       max=300


SSEEEE AALLSSOO
       _g_._r_e_m_o_v_e, _g_._r_e_n_a_m_e, _i_._f_f_t, _i_._i_f_f_t, _r_._m_a_s_k

AAUUTTHHOORR
       Bill Brown, U.S. Army Construction Engineering Research Laboratory

       Additional flag/min/max parameter by Markus Neteler, University of Han-
       nover

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_4 _$



GRASS 5.0							   r.circle(1)
