Click here to see the SAS code. 
Click here to see the example.

See my blog for more information about this graph!


Here's how I got the data ...

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   http://www.ngdc.noaa.gov/mgg/gdas/gd_designagrid.html
   Your Grid Id: bobsas1
   Grid Database: ETOPO2 - 2-minute global relief
   x - Windows

   Lat/Lon (left defaults - lat(up/down) = 19N-23N , lon (across)=86(30min)W-92W
   Cell size - 2-minute  
   Cell params - changed to 4-byet floating pt, tenths of meters
   Format: XYZ (lon,dat,depth), No Header, Space delimited, omit empty grid cells

   Clicked 'Design-A-Grid' button.
   Clicked 'Next-->' button
   Clicked 'Compress and Retrieve' button
   Clicked 'Retrieve' button
   Clicked 'save'
   Saved bobsas1.zip to my U:
   Then, after saving it, I unzipped it, which created a directory structure...
   There's a lot of 'junk', but the file I wanted was ...

      /u/realliso/bobsas1_data/bobsas1/bobsas1.xyz
      (I renamed that to crater.xyz in the current directory)

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