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6.8 Graphics and the Cursor - Locating Specific Positions Using the Cursor

In this exercise, you will use the STNLIST command to find the station ID for Charleston, West Virginia, position the cursor at that location using the PC command, display its earth coordinates using Alt E, and list the towns closest to Charleston with the TOWNS command. Then you'll follow the same procedure for Montreal, Canada using the S command instead of TOWNS. You will also use the STNPLOT command to plot all of the RAOB stations on your image.

  1. Display the latest Meteosat-3 Visible image on frame 2 centered over Bangor, Maine. Add a high resolution map.

    Type: IMGDISP BLIZZARD/M3-VIS 2 STA=KBGR SF=Y;MAP H

  2. List all of the Metar stations in West Virginia.

    Type: STNLIST ST=WV TYPE=M

    The Metar stations in West Virginia are listed, including their station number, station ID, data types, state and country, earth coordinates, and elevation, as shown below.

    STNLIST ST=WV TYPE=M R                                                               
 IDN  ID     Station Name         Data Types      ST CO  LAT        LON        ELE
72412 KBKW   Beckley              M 36 T          WV US   37:47:42   81:07:29   763
 ---  KBLF   Bluefield            M    T          WV US   37:17:45   81:12:28   871
 ---  KCKB   Clarksburg           M    T          WV US   39:18:00   80:13:29   366
72414 KCRW   Charleston           M 36 T          WV US   38:22:46   81:35:29   299
72417 KEKN   Elkins               M 36 T          WV US   38:53:07   79:51:10   605
 ---  KHLG   Wheeling             M    T          WV US   40:10:13   80:38:40   364
72425 KHTS   Huntington           M 36 T          WV US   38:21:54   82:33:18   252
 ---  KLWB   Lewisburg / Greenbri M    T          WV US   37:52:00   80:24:00   702
 ---  KMGW   Morgantown           M    T          WV US   39:38:58   79:55:16   380
 ---  KMRB   Martinsburg          M    T          WV US   39:24:07   77:59:04   170
 ---  KPKB   Parkersburg          M    T          WV US   39:20:42   81:26:21   262
 ---  KRLX   Charleston           M               WV US   38:19:00   81:43:00   364
 ---  KSSU   White Sulphur Sprng  M               WV US   37:46:00   80:20:00   549
 ---  KW99   Petersburg           M               WV US   38:59:00   79:08:00   293
Number of stations listed: 14
STNLIST: Done

  3. List the stations in West Virginia that include CHARLESTON in the name.

    Type: STNLIST ST=WV MATCH=CHARLESTON

    STNLIST ST=WV MATCH=CHARLESTON                                                      
 IDN  ID     Station Name         Data Types      ST CO  LAT        LON        ELE
 ---  RLX    CHARLESTON                    N      WV US   38:18:40   81:43:23   415
 ---  CRW    Charleston                   F       WV US   38:22:46   81:35:29   299
 ---  CRW    CHARLESTON                        V  WV US   38:22:00   81:36:00   299
 ---  HCV    CHARLESTON                        V  WV US   38:22:00   81:36:00     0
 ---  HVQ    CHARLESTON                        V  WV US   38:22:00   81:36:00     0
72414 KCRW   Charleston           M 36 T          WV US   38:22:46   81:35:29   299
 ---  KRLX   Charleston           M               WV US   38:19:00   81:43:00   364
 ---  RLX    CHARLESTON                     W     WV US   38:18:47   81:43:07     0
Number of stations listed: 8
STNLIST: Done
  4. Position the cursor over Charleston.

    Type: PC L KCRW

    The PC command places the cursor over the designated location (L indicates location) on the displayed frame.

  5. Display the coordinates at the cursor position.

    Press: Alt E

    Notice that the latitude and longitude are the same as those listed in the STNLIST output.

     Frame    Latitude    Longitude    Tvline    Tvelem    Line    Elem         
     2    38:22:45    081:35:38      341        94      821    2255

  6. List the towns closest to Charleston and then press alt-Q to quit the TOWNS command.

    Type: PC L KCRW;TOWNS
    Press: Alt G
    Press: Alt Q

  7. If you would like to enter the current lat/lon position of your cursor onto the command, you can press the Ctrl button on your keyboard and the left mouse button simultaneously. Enter a lat/lon pair into an IMGPROBE command using this method.

    Type: IMGPROBE MODE=N LATLON= - but don't press Enter!
    Press: Ctrl LeftMouseButton
    Press: Enter

    This should give you the image information for your current cursor location.

  8. Find the country code for Canada, as you will need it for the CO keyword in step 8.

    Type: CCODE CANADA

  9. Find the station code for Montreal.

    Type: STNLIST CO=CA MATCH=MONTREAL

    The text window lists eight stations in Montreal, as shown below. Use the 4-letter station code for Montreal/Dorval.

    STNLIST CO=CA MATCH=MONTREAL                                                         
 IDN  ID     Station Name         Data Types      ST CO  LAT        LON        ELE
 ---  CWGJ   Montreal River Radar M                  CA   47:14:00   84:31:00   559
71675 CWPQ   Montreal-Est         M 36               CA   45:38:00   70:33:00    51
 ---  CYMX   Montreal / Mirabel   M    T             CA   45:41:00   74:02:00    82
71627 CYUL   Montreal / Dorval In M 36 T             CA   45:28:00   73:45:00    31
 ---  IDO    MONTREAL                          V  QB CA   45:28:00   73:45:00     0
 ---  UTM    ST MATHIAS/MONTREAL               V  QB CA   45:20:00   73:16:00     0
 ---  WAO    MONTREAL                          V  QB CA   45:28:00   73:45:00     0
 ---  YMX    MONTREAL                          V  QB CA   45:50:00   74:23:00    82
 ---  YUL    MONTREAL P.Q.                     V  QB CA   45:31:00   73:58:00    36
Number of stations listed: 9
STNLIST: Done

  10. Position the cursor at Montreal.

    Type: PC L CYUL

  11. Display the coordinates at the cursor position.

    Press: Alt E

  12. List the Metar, Synoptic and RAOB stations that are closest to Montreal.

    Type: PC L CYUL
    Press: Alt S

  13. Plot all of the RAOB stations that are within the navigation of your image frame.

    Type: STNPLOT TYPE=R


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