Plotting Data using VisAD

VisAD is a Java component library for data visualization. Its powerful and sophisticated java classes can be incorporated into your code to allow viewing of 2 or 3 dimensional data. In the example shown below, we write a data set that can be read and plotted using a spreadsheet program that comes with the VisAD package.

To plot data from an external data source using VisAD's spreadsheet, one must read the data from a file and plot the points. As a simple example, a Java program from PH265 has been adopted to output data files that are compatible with VisAD.

• Java file for creating data files to be read into the VisAD spreadsheet
  • EqHeat.java to create file with comma separated values (simple z values)
• Data file that has already been created by Java programs:
  • EqHeat.csv for plotting with VisAD spreadsheet
• VisAD source file (local download, right click to save as file)
  • No need to unpack class files
  • to use classes set classpath with:
    • >setenv CLASSPATH /home/user/visadf/visad.jar:.
• VisAD examples files (local) to see the power of VisAD
  • Unpack examples with >jar xvf visad_examples.jar

The VisAD spreadsheet is a simple application that allows you to plot one or more data files. To run the spread sheet, enter

>java visad.ss.SpreadSheet (if more memory required use >java -mx64m ...)

Then open the data file you would like to plot. To plot only one file it is helpful to delete the second row and column. To change the way the data is plotted click on edit mapping.

Further notes on VisAD

Update 3.4.02
© D. H. McIntyre