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>From: Rebecca Ratz <address@hidden> >Organization: UCAR/Unidata >Keywords: 200205202056.g4KKu1a04652 > >I am currently conducting a summer research session on using GEMPAK. I >am hoping someone might be able to talk me through some of the problems >that I am encountering. > >My goal is to write a file that contains temperature, precipitation, >and lightning data on one map. I'm having trouble tweeking the >background color, contouring, etc. Everytime I try using the variable >BND=bg/31,to produce a white background, the program pops back staying >that "BND" is an unrecognized parameter. Some examples of the contouring >and coloring that I am looking for can be seen at... > >http://twister.sbs.ohio-state.edu/surface/mw.gif >http://www.comet.ucar.edu/resources/cases/mapindex.htm > >The first website contains the background and state boundary looks that I >was hoping for. As for the contouring, shading and darkening of colors >in second web address...can you tell what function is used to produce >such a picture? > BND is a parameter in GPMAP used for filling geographically defined boundaries as show below. It is not a parameter in SFMAP for example, which is the plot you mention in the first example above. To set the background color to white, you have 2 easy options. 1) if you are running interactively on the desktop, pop up the ncolor program from the ntl bar. Then, click on the leftmost color tile "0" and set the color to white. 2) An alternative to the above, and generally the easiest way if you are running scripts to create maps is to copy the $GEMTBL/colors/coltbl.xwp to the directory where you are running your GEMPAK programs and change the first color line in the file from: BLACK BLA 0 0 0 black to WHITE WHI 255 255 255 white By default, GEMPAK will use the coltbl.xwp file in your current working directory if it exists, and if not, look for the file in $GEMTBL/colors. Secondly, the topographic images are stored in AREA files wich can be displayed using the SATFIL parameter. The topography files can be found in $GARPHOME/map/areas. To use these, set PROJ=sat in your display program, and then SATFIL=$GARPHOME/map/areas/topo_na.area for example. Or, in GPMAP, you can use the BND parameter to create a filled map like: http://motherlode.ucar.edu/unidata/images/nids/radar_mosaic.gif In this image, I first use GPMAP to color the map areas, then display the radar data over top in gdplot2. In GPMAP I used: MAP = 32 GAREA = 22.0;-122.0;47.0;-65.0 PROJ = lcc/25;-103;60/3;3;0;0 $MAPFIL = hipowo.cia BND = bg/24+world_bnds/8+lakes/24 then, in your overlaying program, set CLEAR=NO. Steve Chiswell Unidata User Support > >Thanks for your time, it is greatly appreciated? > > >Rebecca Ratz > >address@hidden >University of Michigan >Undergraduate in Mechanical Engineering > > > >