ION Java User's Guide: Using ION's Pre-Built Applets

IONPlotApplet

The IONPlotApplet displays an IDL plot. The X and Y values of the plot and any IDL plot properties supported by ION can be set through parameters to the applet.

Parameters

In addition to the parameters described in Parameters Specified via <PARAM> Tags, the IONPlotApplet accepts the following parameters:

X_VALUES

Set the value of this parameter equal to a valid IDL expression that evaluates to a vector of X data. If X_VALUES is not specified, the data in Y_VALUES is plotted as a function of point number (starting at zero). If both arguments are provided, Y_VALUES is plotted as a function of X_VALUES.

Y_VALUES

Set the value of this parameter equal to a valid IDL expression that evaluates to a vector of Y data.

plot_property_1, ..., plot_property_n

Here, plot_property_* is the name of a plot property supported by the IONGrPlot class. Properties for the IONPlotApplet reflect the capabilities implemented in keywords to the IDL PLOT procedure.

The syntax above refers to the fact that you can supply more than one plot property to the applet via the <PARAM> tag. In the example in the next section, both TITLE and LINESTYLE are plot properties, with values of "Plot" and "2," respectively.

The following IDL Plot properties are supported by IONPlotApplet. Refer to the IDL documentation on keywords available for use with the PLOT procedure for an explanation of each property:

BACKGROUND, CHARSIZE, CLIP, COLOR, DATA, DEVICE, FONT, LINESTYLE, NOCLIP, NODATA, NOERASE, NORMAL, POSITION, PSYM, SUBTITLE, SYMSIZE, T3D, TICKLEN, TITLE, MAX_VALUE, MIN_VALUE, NSUM, POLAR, XLOG, YNOZERO, YLOG, ZLOG

Example

The following example creates an IONPlotApplet that connects to the same server used by the "Connection" applet defined in the IONGraphicApplet example. The applet generates some data for the X value of the plot, and sets the "Title" and "Linestyle" properties of the plot.

<APPLET NAME="PLOT" CODE=IONPlotApplet.class  
        WIDTH=200 HEIGHT=200  
        ARCHIVE="ion_64.zip"  
        CODEBASE=../classes>  
    <!-- This applet uses the applet 'CONNECTION' to connect  
        to the server -->  
    <PARAM NAME="ION_CONNECTION_NAME" VALUE="CONNECTION">  
    <PARAM NAME="LINK_URL" VALUE="plotappletsrc.html">  
    <PARAM NAME="X_VALUES" VALUE="exp(-(shift(dist(30), 15,  
        15)/7)^2)">  
    <PARAM NAME="TITLE" VALUE="Plot">  
    <PARAM NAME="LINESTYLE" VALUE="2">  
</APPLET>