Announcing automatic map labels and high-res maps

From: Mary Haley (haley AT XXXXXX)
Date: Mon Feb 04 2002 - 17:34:00 MST

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    Dear NCL users,

    We are very pleased to announce two new major features in NCL with
    regard to maps:

     1. You can have lat/lon labels automatically generated for
        several map projections. This feature has not been incorporated
        into the gsn_csm* functions yet.

        To generate map tickmarks automatically (if you are not using
        gsn_csm functions), set the "pmTickMarkDisplayMode" resource to
        "Always" when you are setting the map resources. (See example at
        the end of this message.)

        For more information, see the resource documentation at:

    http://ngwww.ucar.edu/ngdoc/ng/ref/hlu/obj/MapPlot.obj.html#TickMarks

     2. You can access the multi-resolution coastline database RANGS
        (Regionally Accessible Nested Global Shorelines), developed by
        Rainer Feistel from Wessel and Smith's GSHHS (Global
        Self-consistent Hierarchical High-resolution Shoreline)
        database.

        To access the RANGS/GSHHS database, you must first download it
        from Rainer Feistel's web site at:

            http://www.io-warnemuende.de/homepages/rfeistel/index.html

        Right before the section entitled "Some WWW Links", you should
        see a little table with ten *.zip files to download:

               rangs(0).zip gshhs(0).zip
               rangs(1).zip gshhs(1).zip
               rangs(2).zip gshhs(2).zip
               rangs(3).zip gshhs(3).zip
               rangs(4).zip gshhs(4).zip

        You must download all ten of these files, unzip them, and
        either put them in the default directory
        "$NCARG_ROOT/lib/ncarg/database/rangs", or put them somewhere
        else and set the environment variable NCARG_RANGS to this
        directory. The files take up about 140 megabytes, unzipped.

        Once you have the files in the appropriate location, then set
        the "mpDataBaseVersion" resource to "RANGS_GSHHS" to create maps
        using this database. (See example at the end of this message.)
        Note: you should not use this database to plot maximal area plots,
        because 1) you will get horizontal lines through your plot, and 2) it
        takes a long time. If this is going to be a problem for you, send
        me email at haley@ucar.edu.

        For more information, see the resource documentation at:

    http://ngwww.ucar.edu/ngdoc/ng/ref/hlu/obj/MapPlot.res.html#mpDataBaseVersion

    Note: the example below uses the generic "gsn_map" function to plot up
    a cylindrical equidistant plot with automatic map labels. The first
    plot uses the default resolution, and the second one uses the
    RANGS/GSHHS database. Note that if you don't have this database
    installed, you will get an error message. Also, the second plot will
    take longer to plot.

    You must have at least version 4.2.0.a022 of NCL to run this example!

    Cheers,

    --Mary

    load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

    begin
    ;
    ; Create an XWorkstation object.
    ;
      wks = gsn_open_wks("x11","plot")
    ;
    ; Set up some map resources.
    ;
      mpres = True
      mpres@gsnMaximize = True
      mpres@mpLimitMode = "LatLon"
      mpres@mpMinLonF = -15.
      mpres@mpMaxLonF = 15
      mpres@mpMinLatF = 40.
      mpres@mpMaxLatF = 70.
      mpres@pmTickMarkDisplayMode = "Always"
    ;
    ; Draw a cylindrical equidistant map, with the above resources set.
    ;
      map = gsn_map(wks,"CylindricalEquidistant",mpres)

    ;
    ; Draw a cylindrical equidistant map using the RANGS/GSHHS database.
    ;
      mpres@mpDataBaseVersion = "RANGS_GSHHS"
      map = gsn_map(wks,"CylindricalEquidistant",mpres)

    end



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