xm_ellipse

NAME
     xm_ellipse - Ellipse format for the xmap8 program

SYNOPSIS
     xm_ellipse - Input File Format

DESCRIPTION
     Ellipses are stored in a simple ascii format in free format.
     You  can  load ellipses by using the -E <filename> option or
     by reading them in with  the  menu  option  "Get  Ellipses".
     Toggling  the  "Plot Ellipses" button will turn the plotting
     on or off.



FORMAT
     The format for ellipses comes in 2 "styles".

     The first simple style involves only 3 parameters:  DX,  DY,
     and DZ and will provide a simple plot of an ellipse oriented
     along the N-S, E-W, Z axes.

     The second format provides the 6 elements of the  covariance
     matrix describing the ellipsoid. In this case ellipsoids are
     plotted such the viewer sees the outline of the full  ellip-
     soid projected onto the viewers plane.

     ------------------------
     Format 1:
     name LAT LON DEPTH DX DY DZ

     ------------------------
     Format 2:
     name LAT LON DEPTH XX XY XZ YY YZ ZZ

     so that DX = sqrt(XX), DY = sqrt(YY), DZ = sqrt(ZZ)



UW FORMAT
     Since UW pickfiles have the E card separate from the A-card,
     or  hypocenter  card,  all  you  have  to do is run a simple
     script to combine the two into an  xmap8  ellipse  card.   I
     have provided a simple Perl script to do this.
     PERL SCRIPT:
     #!/usr/local/bin/perl

     # program reads a pickfile in UW format,
     #   extracts information from the A-card and E-card
     #   returns an xmap8 ellipse card
     #                   J. M. LEES Sun Oct  1 01:18:42 EDT 1995

     while(<>){

        $kind = substr($_,0,1);

         if($kind eq "A") {

              #print "got an A card: $_ 0 ;

     #A 8005190129 30.25 46N1276 122W1108 19.44  2.6 26/000 051 04 0.35 00.7CA C1
     #c...|....1....|....2....|....3....|....4....|....5....|....6....|....7.$

               $type = substr($_, 1, 1 );
               $id= substr($_, 2, 10);
               $sec = substr($_, 12, 6);
               $lat1 = substr($_ ,19, 2);
               $NS = substr($_, 21, 1);
               $lat2 = substr($_, 22, 4);
               $lon1 = substr($_, 27, 3);
               $EW = substr($_, 30, 1);
               $lon2 = substr($_, 31, 4);
               $depth = substr($_, 35, 6);
               $mag = substr($_, 43, 3);
               $nump = substr($_, 46, 3);
               $JU = substr($_, 49, 1);
               $nums = substr($_, 50, 3);
               $gap = substr($_, 54, 3);
               $delta = substr($_, 57, 3);
               $rms = substr($_, 60, 5);
               $err = substr($_, 65, 5);
               $q1 = substr($_, 70, 1);
               $q2 = substr($_, 71, 1);
               $modid = substr($_, 73, 2);


              $latdd = $lat1 + $lat2/6000.0;
              $londd = $lon1 + $lon2/6000.0;

     if($EW eq "W") { $londd = -$londd; }
     if($NS eq "S") { $latdd = -$latdd; }

          }

         if($kind eq "E") {
               $dx = substr($_, 46, 4 );
               $dy= substr($_, 51, 4);
               $dz = substr($_, 56, 4);

     #E LQ 0.152 0.061 0.159 0.145 2266.93   9      1.69 2.11 3.48 0.21 0.00 0.00
     #Vel,RMS,MeanRMS,SDabout0,SDaboutMean,SSWRES,NDFR,FIXXYZT,SDx,SDy,
     #      SDz,SDt,Mag,StErrMag,MeanUncert
     #FORMAT('E',1x,A2,4(1x,f5.3),1x,F7.2,1x,I3,1x,4A1,4(1x,F4.2),3(1x,F4.2)
     #                                               dx    dy   dz   dt
     #E VV RR.RR M.MMM S.SSS S.SSS WWWW.WW NNN XYZT D.DD D.DD D.DD D.DD M.MM S.SS U.UU
     #0c...|....1....|....2....|....3....|....4....|....5....|....6....|....7.$

     # OUTPUT ELLIPSE CARD:

     printf("%s  %f   %f  %f   %f %f %f0,$id, $latdd, $londd,  $depth, $dx, $dy, $dz );
        }
        }


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