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



NNAAMMEE
       vv..iinn..ttrraannsseeccttss	-  import transect data to a GRASS vector
       map
       _(_G_R_A_S_S _V_e_c_t_o_r _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       vv..iinn..ttrraannsseeccttss
       vv..iinn..ttrraannsseeccttss hheellpp

       vv..iinn..ttrraannsseeccttss [--aa] iinnppuutt==_n_a_m_e
	      [ffss==_c_h_a_r_a_c_t_e_r"]	   lleennggtthh==_v_a_l_u_e      [uunniittss==_n_a_m_e]
	      [ddeeccll==_n_a_m_e] vveecctt==_n_a_m_e [TTIITTLLEE==_n_a_m_e"]




DDEESSCCRRIIPPTTIIOONN
       vv..iinn..ttrraannsseeccttss  imports	"transects"  into  a GRASS vector
       map. A transect is a line (or an area) which is	described
       by  a  starting	coordinate,  a	direction or azimuth, (or
       backward, forward, rightside, and leftside distances  from
       the  line transect), and a length (in meters or feet). The
       information describing the transects must  be  in  a  file
       prepared  by  the user before running vv..iinn..ttrraannsseeccttss..  The
       format of this file is  described  below  in  the  section
       ""TTRRAANNSSEECCTT FFIILLEE FFOORRMMAATT""..



OOPPTTIIOONNSS
   FFllaaggss::
       --aa     Run  for area transects. Default is line transects,
	      i.e., this flag is not used.






   PPaarraammeetteerrss::
       iinnppuutt  transect information file


       This is the file containing the transect information to be
       imported.   The	format of this file is described below in
       the section ""TTRRAANNSSEECCTT FFIILLEE FFOORRMMAATT""

       ffss     input data field separator


       The transect file is organized one transect per line  with
       at  least 4 fields.  The _f_s option specifies the character
       that is used in the transect information file to  separate
       the  fields.  If  not  specified, fields are assumed to be
       separated by blanks (white space).  (Quote  the	delimeter
       whenever  you  are not sure whether it has special meaning
       in UNIX or not, to avoid the misunderstanding by GRASS.)

       lleennggtthh transect length


       This is the length of the transects (default  is  in  grid
       units,  e.g.,  meters).	 It is assumed that all transects
       have the same length. If they do not, then more	than  one
       import  process	must  be run to create two or more vector
       files and the results patched together (using v.patch ).

       uunniittss  units of the length
	      default: meter


       This is the unit of the transect. It can be meter or foot.

       ddeeccll   declination  -  angle  (in  degrees) to be added to
	      input azimuth angles
	      default: 0


       Each transect has a direction or azimuth angle  associated
       with it. The map projection may have a declination associ-
       ated with it and if the azimuth	angles	embedded  in  the
       transect  input	file do not account for this declination,
       it may be specified here.

       vveecctt   Vector map to be created

       TTIITTLLEE  Title for resultant vector map
	      default: Transect map


       If TITLE is more  than  one  word,  it  should  always  be
       quoted.




TTRRAANNSSEECCTT FFIILLEE FFOORRMMAATT
       The format for the transect file consists of one record or
       line per transect  with	4  mandatory  fields  and  a  5th
       optional  field for line transects. The first field is the
       GRASS category number to be assigned to the transect.  The
       second  and  third  fields  are	the  easting and northing
       (respectively) of the starting coordinate  for  the  tran-
       sect.   The  fourth field is the azimuth in degrees clock-
       wise from north of the  transect.   Following  the  fourth
       field  is  an  optional	fifth  field that is the category
       label for the transect. The following is a simple  example
       with 3 transects:



       1 709818   5453991   246.0   P CLGR 4 73 1 21 0 0 0 0 1
       2 698350   5464162   128.0   P CLGR 0 55 0 36 0 0 0 0 1
       3 704615   5461874   190.5   P DEGR 0 34 4 15 0 0 0 0 0

       Note  that  the	fifth  field  (i.e., the label) is really
       everything after the azimuth, not just the P.


       This file could be formatted as follows:



       1:709818:5453991:246.0:P:CLGR:4:73:1:21:0:0:0:0:1
       2:698350:5464162:128.0:P:CLGR:0:55:0:36:0:0:0:0:1
       3:704615:5461874:190.5:P:DEGR:0:34:4:15:0:0:0:0:0

       In this case the fields are separated by a colon  so  _f_s_=_:
       must  be specified on the command line. The labels (start-
       ing with the P) would retain the colons	(i.e.,	they  are
       not  removed from the label even though they act to define
       the first 4 fields).




       When area  transects  are  required,  the  transects  file
       should include four (4) more fields for backward, forward,
       rightside, and leftside distance  from  the  corresponding
       line transect. The format will be as the following:



       1    709818    5453991	246.0	10.0   15.0   20.0    5.0
       P CLGR 4 73 1 21 0 0 0 0 1
       2   698350   5464162   128.0    5.0   15.0    10.0    25.0
       P CLGR 0 55 0 36 0 0 0 0 1
       3    704615    5461874	190.5	15.0   20.0   10.0    5.0
       P DEGR 0 34 4 15 0 0 0 0 0

       Note that delimiter could be other  than  white	space  in
       transect  file. Vector files of line transects can be gen-
       erated from the above area transects file by not using  _-_a
       flag. However, the label will include four (4) more items.





NNOOTTEESS
       The resulting vector map is a complete GRASS  vector  map:
       it  will  have  a  category  file with the labels from the
       input file and it will  have  the  topology  file  already
       built.  ( v.support is run automatically by vv..iinn..ttrraannsseeccttss
       as the final step in creating the GRASS vector map.)



AAUUTTHHOORRSS
       Tao Wen, University of Illinois at Urbana-Champaign, Illi-
       nois.
       Michael	 Shapiro,   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.transects(1)
