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>From: "Greg Salottolo" <address@hidden> >Organization: NTSB >Keywords: 200501051815.j05IFvGr025053 IDV track Hi Greg- >Institution: NTSB >Package Version: 1.2b1 >Operating System: os.name:Windows XP; os.arch:x86; os.version:5.1; >Hardware Information: java.vendor:Sun Microsystems Inc.; java.version:1.4.2_01 > ; java.home:C:\\Program Files\\IDV_1.2b1\\jre; >Inquiry: Good Afternoon: > >I am not having much luck trying to find out how to generate a flight track fi > le (lat/lon/alt) that can be imported and displayed in IDV. Can you offer som > e >suggestions? You'd need a netCDF file of the form: netcdf UnidataTestFileMN { dimensions: time = UNLIMITED ; // (229 currently) variables: int time(time) ; time:units = "seconds since 2002-10-25 0:00:00 0:00" ; time:long_name = "Time offset from base_time" ; time:_FillValue = -99999 ; time:missing_value = -99999 ; float altitude(time) ; altitude:units = "km" ; altitude:long_name = "altitude MSL" ; altitude:_FillValue = -99999.f ; altitude:missing_value = -99999.f ; float latitude(time) ; latitude:units = "degrees_N" ; latitude:long_name = "north latitude" ; latitude:valid_range = -90.f, 90.f ; latitude:missing_value = -99999.f ; latitude:_FillValue = -99999.f ; float longitude(time) ; longitude:units = "degrees_E" ; longitude:long_name = "east longitude" ; longitude:valid_range = -180.f, 180.f ; longitude:missing_value = -99999.f ; longitude:_FillValue = -99999.f ; (I got this file from either you or Grant Petty). From the File Chooser, set the Data Source Type to be a Track file, select the file you want to display and click Add Source. In the Data Selector, you should see a Track tab and a Point Display field in the Fields pane. Expand the Track tab and select one of the fields (e.g. Latitude). In the Displays pane, select "Track colored by Parameter", then click the "Create Display" button. That should create the display of the track. Now, if you want to see an airplane in your display for the craft's position, do the following. From the Data Selector window, select the Point Display Field and the Point Data Plot display, then click Create Display. From the Point Display's control window, click on the little edit icon (paper and pencil) on the right of the Change button to bring up the Station Model Editor (this will change to Point Data Plot editor probably in a future release). From the editor's File menu, select the New menu. In the dialog, type in a name for this model (e.g. Airplane). Now, click on the Shape item in the list of objects, then click on the middle of the editing canvas (white panel with cross). This will place a shape on the canvas. Right click on the shape and use the Center->Center menu to center the shape on the display point (lat/lon/alt). Right click again and bring up the Properties dialog. In the Display tab, select the type of shape you want to put at each point (e.g. 3-D Airplane). Click on the OK button. Now, in your Point Display Control window, click the Change button and select your new model from the list. You should see the airplane in the main display. Turn on the animation and watch it move with time. You can speed up the animation using the animation control ("i" icon on the animation control bar). Bring up the Station Model Editor again and bring up the Properties dialog. Click on the Rotate By tab. For the Rotate By Parameter field, type in "Direction". (I calculate a heading based on the difference between the lat/lon points. If you have a heading parameter in the file, use that name instead). For the Data Range, set the range to be 0 to 360. Leave the unit as Default. Leave the Degrees as 0 and 360. Now click OK. As the plane flies along the track, it will be rotated by the directional heading. (Sorry this isn't really documented). That should get you going. You can create different station models depending on what you want to display. For example, you could add in a value glyph to plot the lat/lon/alt at each point. See: http://my.unidata.ucar.edu/content/software/idv/docs/userguide/tools/StationModelEditor.html in the User's Guide for more info (or Help->User's Guide menu and then the Tools->Station Plot Model Editor section in the IDV). That is left as a simple exercise to the reader. ;-) Enjoy. Don Murray NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.