v.in.dlg2(1)	       Grass User's Manual	     v.in.dlg2(1)



NNAAMMEE
       vv..iinn..ddllgg22  - Converts an ASCII or binary USGS DLG-3 (bdlg)
       file to a binary GRASS vector (dig) file.
       _(_G_R_A_S_S _V_e_c_t_o_r _D_a_t_a _I_m_p_o_r_t _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       vv..iinn..ddllgg22
       vv..iinn..ddllgg22 hheellpp
       vv..iinn..ddllgg22 [--bbll] iinnppuutt==_n_a_m_e oouuttppuutt==_n_a_m_e

DDEESSCCRRIIPPTTIIOONN
       This program  converts  an  ASCII  or  binary  USGS  DLG-3
       (_d_l_g_._o_l_d  or  _b_d_l_g_._o_l_d)	file  into  a binary GRASS vector
       (dig) file.


       _v_._i_n_._d_l_g_2 also creates a dig_att file containing the label
       information  'stripped' from the DLG-3 file.  However, the
       user must run _v_._s_u_p_p_o_r_t (or _v_._i_m_p_o_r_t option 4) on the _o_u_t_-
       _p_u_t  file  created  by _v_._i_n_._d_l_g_2 to create a dig_plus file
       containing the file topology, before using the _o_u_t_p_u_t file
       in _v_._d_i_g_i_t.


       The user can avoid this two-step process by converting the
       ASCII or binary DLG-3 file to binary GRASS  vector  format
       using option 1 or 2 of the GRASS program _v_._i_m_p_o_r_t.

OOPPTTIIOONNSS
   FFllaaggss::
       --bb     Input is a binary DLG-3 file (default is ASCII).

       --ll     Give  precedence	to  line  information (default is
	      area).


   PPaarraammeetteerrss::
       iinnppuutt==_n_a_m_e
	      Name of USGS DLG-3 Optional format input file.

       oouuttppuutt==_n_a_m_e
	      Name to be assigned  to  the  binary  GRASS  vector
	      files created.

       If  the	user  simply  types  vv..iinn..ddllgg22 without specifying
       parameter values on the command	line,  the  program  will
       prompt the user to enter these.

NNOOTTEESS
   AArreeaa vvss LLiinnee PPrreecceeddeennccee::
       Some  machine-processed	DLG-3  files do not make the dis-
       tinction between line edges and area edges.  For  example,
       in a roads map, where the desired information is line edge
       data, a downtown block surrounded by  roads  may  be  pro-
       cessed  as an area.  Because of this, the user is asked to
       choose whether to give precedence to areas or  lines.   If
       precedence  is  given  to  lines, the user should be aware
       that any lines that bound unlabeled  areas  in  the  DLG-3
       file  will  be  stored  as line data.  Any unlabeled areas
       would therefore be lost (this is only a concern when areas
       are   unlabeled;    labeled   area   information  will  be
       retained).  If precedence is given to areas, lines will be
       stored as boundaries to areas that are unlabeled.

   BBuuiillddiinngg ssuuppppoorrtt ffiilleess wwiitthh
       _v_._s_u_p_p_o_r_t: When you run _v_._s_u_p_p_o_r_t you will have the option
       of snapping the nodes in your vector file that fall within
       a certain threshold of one another.  WARNING:  the default
       threshold is calculated using the scale	of  the  original
       DLG-3 file.  If the threshold is too high, excessive snap-
       ping may occur, destroying the file!!  With _v_._s_u_p_p_o_r_t, the
       user has the option of snapping or not snapping nodes, and
       further, of setting a particular snapping threshold.

SSEEEE AALLSSOO
       _v_._d_i_g_i_t, _v_._i_m_p_o_r_t, _v_._s_u_p_p_o_r_t

AAUUTTHHOORR
       Michael	 Higgins,   U.S.Army   Construction   Engineering
       Research Laboratory
       Dave  Gerdes,  U.S.Army	Construction Engineering Research
       Laboratory

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_5 _$



GRASS 5.0					     v.in.dlg2(1)
