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



NNAAMMEE
       vv..iinn..ddllgg   - Converts an ASCII USGS DLG-3 Optional 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..ddllgg
       vv..iinn..ddllgg hheellpp
       vv..iinn..ddllgg   [--ll]	 iinnppuutt==_n_a_m_e    oouuttppuutt==_n_a_m_e    [mmaatttt==_n_a_m_e]
       [bbaassee==_v_a_l]

DDEESSCCRRIIPPTTIIOONN
       This  program converts an ASCII USGS DLG-3 (_d_l_g) file into
       a binary GRASS vector (dig) file. Store the DLG-file  into
       $LOCATION/dlg/  (create	this  directory,  if  not  there)
       before importing.


       WWaarrnniinngg:  The program reads DLG-3 Optional format only.


       _v_._i_n_._d_l_g also creates a dig_att file containing the  label
       information  'stripped'	from  the  DLG-3  file (the first
       minor attribute for each record unless mmaatttt is specified).


       If  the	mmaatttt is specified, _v_._i_n_._d_l_g creates an additional
       attribute file containing  identifiers  for  every  record
       with  correspon	ding  multiple	attributes.  In this case
       mmaatttt file contains identifiers starting with base bbaassee for
       the  attributes	stored	in  mmaatttt  file (as opposed to the
       first minor attributes with no mmaatttt file).  The example of
       mmaatttt with bbaassee = 34 would be:

	    34	 0    0
	    35	 180  201
	    36	 180  208
		 170  240
		 190  201
	    37	 160  220

       With the corresponding _d_i_g___a_t_t looking like this:

	    A 648467.190000 4456367.320000     34
	    L 667989.290000 4458393.520000     35
	    L 651002.470000 4473793.390000     36
	    L 663816.680000 4471412.080000     37

       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  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  DLG-3  file  to  binary  GRASS  vector format using
       option 1 of the GRASS program _v_._i_m_p_o_r_t.

OOPPTTIIOONNSS
   FFllaagg::
	--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.

       mmaatttt==_n_a_m_e
	      Name of file with multiple attributes (optional).

       bbaassee==_v_a_l
	      Identifier base for multiple attributes (default is
	      1).



       If  the	user  simply  types  vv..iinn..ddllgg  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
       Dave Gerdes, U.S.Army  Construction  Engineering  Research
       Laboratory
       Irina   Kosinovsky,   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.dlg(1)
