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



NNAAMMEE
       rr..lliinnee  - Creates a new binary GRASS vector (_v_._d_i_g_i_t) file
       by extracting linear features from a thinned raster  file.
       _(_G_R_A_S_S _R_a_s_t_e_r _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       rr..lliinnee
       rr..lliinnee hheellpp
       rr..lliinnee iinnppuutt==_n_a_m_e oouuttppuutt==_n_a_m_e [ttyyppee==_n_a_m_e]

DDEESSCCRRIIPPTTIIOONN
       _r_._l_i_n_e  scans  the named raster map layer (iinnppuutt==_n_a_m_e) and
       extracts thinned linear features  into  the  named  vector
       file (oouuttppuutt==_n_a_m_e).

OOPPTTIIOONNSS
       The  user can run this program either non-interactively or
       interactively.  The program will be run	non-interactively
       if  the	user  specifies  program arguments on the command
       line,  using  the  form:  rr..lliinnee  iinnppuutt==_n_a_m_e   oouuttppuutt==_n_a_m_e
       [ttyyppee==_n_a_m_e]

       If  the	user specifies input raster and output vector map
       names on the command line, any other parameter values left
       unspecified  on	the  command  line  will  be set to their
       default values (see below).   Alternately,  the	user  can
       simply  type  rr..lliinnee  on the command line, without program
       arguments.  In this case, the user will	be  prompted  for
       parameter  values  using  the standard GRASS _p_a_r_s_e_r inter-
       face.

   PPaarraammeetteerrss::
       iinnppuutt==_n_a_m_e
	      Name of existing raster file to be used as input.

       oouuttppuutt==_n_a_m_e
	      Name of new vector file to be output.

       ttyyppee==_n_a_m_e
	      Line type of the extracted vectors; either _l_i_n_e  or
	      _a_r_e_a.   Specifying lliinnee will type extracted vectors
	      as  linear  edges.   Specifying  aarreeaa   will   type
	      extracted vectors as area edges.
	      Options:	_l_i_n_e or _a_r_e_a
	      Default:	ttyyppee==lliinnee



       _r_._l_i_n_e  assumes	that the _i_n_p_u_t map has been thinned using
       _r_._t_h_i_n.

NNOOTTEESS
       _r_._l_i_n_e extracts vectors (aka, "arcs") from a raster  file.
       These  arcs  may  represent linear features (like roads or
       streams), or may represent area edge features (like polit-
       ical  boundaries,  or  soil mapping units).  The attribute
       _t_y_p_e option allows the user to establish the use of either
       linear  or  area  edge attributes for all of the extracted
       vectors.


       _r_._p_o_l_y may be used to extract vectors that represent  area
       features (like soil mapping units, elevation ranges, etc.)
       from a raster file.


       The user  must  run  _v_._s_u_p_p_o_r_t  on  the	resultant  vector
       (_v_._d_i_g_i_t) files to build the _d_i_g___p_l_u_s information.


       _r_._t_h_i_n  and  _r_._l_i_n_e  may  create  excessive nodes at every
       junction, and may create small spurs or	"dangling  lines"
       during  the  thinning  and  vectorization  process.  These
       excessive nodes and spurs may be removed using _v_._t_r_i_m.

BBUUGGSS
       The input raster file MUST be thinned by _r_._t_h_i_n;  if  not,
       _r_._l_i_n_e may crash.

SSEEEE AALLSSOO
       _r_._p_o_l_y

       _r_._t_h_i_n

       _v_._d_i_g_i_t

       _v_._s_u_p_p_o_r_t

       _v_._t_r_i_m

       _p_a_r_s_e_r

AAUUTTHHOORR
       Mike Baba

       DBA Systems, Inc.

       10560 Arrowhead Drive

       Fairfax, Virginia 22030

       _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.line(1)
