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  increas-
       ing  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 nor-
       thing:/ { print $4 }'`
	     r.circle	 -b    out=circle    coordinate=$EASTCEN-
       TER,$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, Uni-
       versity of Hannover

       _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)
