GDMAP plots data from a scalar grid. INPUT PARAMETERS GDATTIM *Grid date/time GLEVEL *Grid level GVCORD *Grid vertical coordinate GFUNC *Grid function GDFILE *Grid file GAREA *Graphics area SKIP *Skip factor POSN *Position COLORS *Color list MARKER *Marker color/type/size/width/hw MAP *Map color/dash/width LATLON *Line color/dash/width/label/inc PANEL *Panel location/color/dash/width CINT *Contour interval/min/max TITLE *Title color/line/title SCALE *Scaling factor DEVICE *Graphics device PROJ *Map projection/angles/margins CLEAR *Clear screen flag TEXT *Text size/font/width/hw flag GRDLBL *Grid point label color PROGRAM DESCRIPTION GDMAP plots data computed from GEMPAK grid files on a map. The variable, POSN, is used to select the position for the data relative to the grid point using the following position numbers: 7 1 3 2 0 4 5 6 8 Position 0 will plot data centered at the station. If an invalid position number is entered, position 0 will be used. The variable, SCALE, is used to scale the data by 10 ** SCALE. The data will be scaled and then rounded to the nearest integer before it is plotted. SKIP specifies the number of grid points to skip when displaying the data. For example, SKIP = 1 displays data at every other grid point in each coordinate direction. SKIP = 0 displays all points. If GRDLBL is not 0, the grid point row and column numbers will be displayed using the color number specified. The grid rows and columns will be centered on the plot area. A map and title may also be included. EXAMPLES 1. The temperature field at 850 mb will be plotted in color 3 at position number 7 which is directly above the station. The data will be plotted at every point for an area centered on California. Markers will be plotted at grid points. The title, "Temperature" will be writted in color 6. GDATTIM = 303/12 GLEVEL = 850 GVCORD = pres GFUNC = tmpc GDFILE = ngm.grd GAREA = ca SKIP = 0 POSN = 7 COLORS = 3 MARKER = 1/5 MAP = 2/2 LATLON = PANEL = 0 TITLE = 6//Temperature SCALE = 0 DEVICE = sg PROJ = mer CLEAR = yes TEXT = GRDLBL = 0 2. Add the dewpoint depression to the plot, in position 8, which is directly below the grid point. The map, markers and title are turned off since they are already plotted. GFUNC = sub[tmpc;dwpt] POSN = 8 MARKER = 0 MAP = 0 TITLE = 0 CLEAR = no 3. Now clear the screen and plot the relative vorticity of the gridded wind, scaled by 10**5, centered at the station in color 1. Add a map and title in color 1. Omit the markers since the data will overlay them. GFUNC = vor[wnd] COLORS = 1 MAP = 1 SCALE = 5 TITLE = 1 MARKER = 0 CLEAR = yes POSN = 0 ERROR MESSAGES [GDMAP -1] Fatal error initializing TAE. [GDMAP -2] Fatal error reading TAE parameters. [GDMAP -3] Fatal error initializing GEMPLT.