xm_origin


NAME
     xm_origin - Origin File format for the xmap8 program

SYNOPSIS
     xm_origin - Input File Format

DESCRIPTION
     The  origin  file  is  required  for  starting  xmap8.    It
     describes  the  layout  and  geometry  of the intended study
     area.  It also describes the map projection used.  There are
     two styles of origin: terse and verbose.


FORMAT
     Terse Origin File:

     This is a simple 3 line file that
     contains the origin and a few other
     important matters concerning the scale of the plot.
     Example:

     0 1 52 52 10 2.0
     33.0 47.0 0.0
     -117.0 10.0 0.



     The first integer numbers refer to the kind of origin file being read.
     0,1 = standard (tomography) style, i.e an origin Lat-Lon pair and
      then number of x,y blocks (in KM)  to the east and
     to the north of the origin.  The origin is always the lower
        left-hand corner (South-West) of the map.

     2 indicates a LAT_LON origin,  i.e. the second and third lines consist of
        Lat-Lon pairs that define the boundaries of the map instead of the origin.
       (e.g. minlat maxlat
             minlon maxlon )

     The second integer indicates the kind of Map Projection.

     0,1 the old version, ellipsoidal projection good for local coordinates.
     2 = Albers Equal Area (spheroidal) projection
     3 =  Mercator Projection
     4 = Miller Projection
     5 = No Projection
     6 = UTM-spherical
     7 = UTM-ellipsoidal
     8 = centered UTM spherical
     9 = centered UTM ellipsoidal


     Grid definition:
     The third (52, in this case) and forth refer to the number of 'blocks'
     (grid divisions) in the x and y- directions respectively.
     The 5-th number is the number
     of 'blocks' in the z-direction (for use on 3D models)  Use this to
     pre-set the MaxDepth parameter.  The 6-th number is the number of km
     per block in the x direction. If a 7-th parameter is provided it is the
     dy, km/block on the y direction.  (So if you like to have everything in
     km use 1.0)


     NEW (Verbose style)
     A more verbose but user friendly method of origin file is now available:
     lines that start with '#' are comments lines.
     E.G.:
     ---------------
     # new origin style input file:
     # file must start with a non-integer alpha character
     # order of cards is not important and spaces are allowed
     # between name = value
     type=0
     proj=0
     nx=30
     ny=50
     nz=10
     dx=5.0
     dy=5.0
     lat=46.4  0.0  0.0
     lon=-123.0  25.0  0.0
     # note lon is positive east!
     #     so longitudes in the western hemisphere should be negative
     #       (minutes and seconds are always positive!)
     # also, you do not need minutes and second if have you only decimal degs
     # note also that comments are allowed starting with '#'
     # and a new parameter 'dy' is included for more flexability
     #  proj=0  lees ellipsoidal projection
     #  proj=1  lees ellipsoidal projection
     #  proj=2  albers equal area
     #  proj=3  mercator
     #  proj=4  miller
     #  proj=5  no projection
     #  proj=6  UTM-spherical
     #  proj=7  UTM-ellipsoidal
     #  proj=8  centered UTM spherical
     #  proj=9  centered UTM ellipsoidal
     ---------------

     Examples:
     -----------------------------------
     Albers Equal Area Map of California:
     1 2 60 64 25 18
     32.0 15.0 0.0
     -125.0 0.0 0.0
     ----------------------------------
     Washington State:
     1 2 640 500 10  1.0
     45.0  0.0  0.0
     -125.0  0.0  0.0
     ---------------------------------
     Japan (this is a lat-lon style origin):
     2 2 70 64 1 60
     29.088596 46.766563
     90.627243   90.981079
     --------------------------------
     Southern Califonia:
     0 0 64 44 1 5.000000
     33.000000 43.000000 37.822266
     -119.000000 12.000000 45.197754
     -----------------------------------


SEE ALSO

xmap8      
xm_color      
xm_hypo      
xm_map       
xm_menu       
xm_origin       
xm_points
xm_raster
xm_station      
xm_well      
xm_wire      
xm_xsec      
xm_ellipse


  • Xmap8: Three-dimensional GIS for Geology and Geophysics.

    REFERENCES see article by J. M. Lees: Lees, J. M. (1995) Xmap8: Three-dimensional GIS for geology and geophysics, Seismological Research Letters: 66, 33-37.

    Address:

      
          Prof. Jonathan M. Lees
          Yale Geology Dept.
          P.O. Box 208109
          New Haven, CT  06520-8109
          (203)432-6947
          lees@love.geology.yale.edu