• Here is an example file: metar.csv. The minimum data required by the IDV is time, latitude and longitude.
• Load the csv file in.
  • In the Data Chooser tree click on the Files node.
  • Go to the point data directory: /data/idv/point/.
  • Select metar.csv and press Add Source.
• The Text Point Metadata Gui will pop up. This allows you to define the metadata for the point data.
  
  
• Using the Text Point Metadata Gui
  • At the top a number of the initial lines from the text data are shown. The arrow buttons allow you to specify where the data starts. Skip the first line.
  • For each column of text data there is a row that shows sample value and allows you to enter a name, unit, date format, missing value and extra information.
  • We're going to skip the "ROW" parameter and define metadata for:
    "Time ","Latitude", "Longitude", "T", "DIR",and "SPD".
  • Note that the time field spans two columns - year and time. The IDV needs to have the time in one column so we use:
    colspan="2"
    This tells the IDV to concatenate columns 1 and 2 and treat them as a single column.
  • Note: the unit for longitude is "degrees_west"
  • Enter the names and units as shown above.
  • You can save these settings for future use.
    • Press the Preferences button and select Save Current.
    • Enter a name, e.g., "workshop"
    • You can reapply these settings with the Preferences button.
  • When done press OK. You can also bring up this GUI in the Data Source Properties Dialog.
• Create the Point Data Plot and change its layout model to "METAR"
• You can also add a special 2 line header to the top of your text file.

   (index) -> (Date,Time,Latitude,Longitude,T,DIR,SPD)
    Time[fmt="yyyy-MM-dd HH:mm:ss"],Latitude[unit="deg"],Longitude[unit="degrees west"],T[unit="celsius"],
          skip,DIR[unit="deg"],SPD[unit="m/s"]
    2008-10-31, 14:00:00,36.773,98.670,9.0,43.0,320.0,1.5
    2008-10-31, 14:00:00,30.317,97.767,16.7,43.0,0.0,0.0
    2008-10-31, 14:00:00,34.398,96.148,13.0,43.0,0.0,0.0
    2008-10-31, 14:00:00,28.973,95.863,17.0,43.0,60.0,1.5
    2008-10-31, 14:00:00,45.150,89.150,8.0,43.0,310.0,2.6
             .......
   

  In the example above, the first line's structure is a VisAD type definition. The second line defines the formatting and units of the parameters. Starting the third line is the data section of this sample. There is more documentation in the User Guide.
• You can also create the data source plugin for your text file.
  • Press the Preferences button and select Write Data Source Plugin.
  • Enter a name of type, e.g., "workshopCSV", and a label, e.g., "workshop csv", and click the OK button.
    
    
  • Enter a plugin name, e.g., "workshop.jar",and check the install box, and click the Write Plugin button.
    
    
  • When the IDV is restarted, the data type "workshop csv" is showing in the list.

Unidata IDV Workshop for version 5.7 > Accessing and Displaying Data > Point Observations