O.3.1 Equidistant labels

Our first example uses the default placement algorithm. Because of the size of the map we request contour labels every 1.5 inches along the lines:

pscoast -R50/160/-15/15 -JM5.5i -Glightgray -A500 -K -P > GMT_App_O_1.ps
grdcontour geoid.grd -J -O -B20f10WSne -C10 -A20+s8 -Gd1.5i -S10 -T:LH >> GMT_App_O_1.ps

As seen in Figure O.1, the contours are placed rather arbitrary. The string of countours for $-40$ to $60$ align well but that is a fortuitous consequence of reaching the 1.5 inch distance from the start at the bottom of the map.

Figure O.1: Equidistant contour label placement with -Gd, the only algorithm available in previous GMT versions.