3.1 Java1489-plotting 3d surfaces using java  (Page 8/24)

A similar discussion holds regarding the two middle plots in Figure 2 . The log version on the bottom identifies the location of the minima more closelythan does the linear plot at the top.

The log of the surface is flatter

You can also see from the bottom right image of Figure 2 that the central peak of the log of the surface is much broader than the central peak for the rawsurface at the top right. This is indicated by the width of the white and yellow areas in the log version as compared to the white and yellow areas in the rawversion.

In addition, the elevations of the log data for the minor peaks at the four sides are almost as high as the elevation of the central peak, as indicated bythe orange or yellow color at the top of the minor peaks.

The elevations of the tops of the four minor peaks at the corners are perhapsseventy-five percent of the elevation of the central peak as indicated by the pinkish color of those minor peaks in the log version.

(Recall that the elevation of the minor peaks at the corners is only about two levels up from the lowest elevation in the raw surface data.)

All of this flattening was caused by converting the raw surface elevations to the log of the surface elevations before producing the surface plot.

Multiple plotting formats are useful

A plotting format that works best for one surface doesn't necessarily work best for all surfaces. Therefore, it is useful for the program to be able toplot the same surface using different plotting formats.

Extremely easy to use

One of the main objectives in the development of this class was to make it very easy to use. No fancy programming is required to use the class and producethe plots. All that is required is to instantiate an object of the class named ImgMod29 , passing an array of data to be plotted along with a few other parameters to the constructor. Basically the parameters (in addition to the data array) specify:

• Which of the three main formats to use, Grayscale, Color Shift, or Color Contour.
• Whether or not to convert to logarithmic values before plotting.
• Whether or not to draw the red axes shown in Figure 1 and Figure 2 .
• How many pixels in the final output should be used to represent a single point on the surface. (For example, the plots in Figure 1 and Figure 2 use a square of nine pixels to represent each point on the 3D surface.)

When an object of the class ImgMod29 is instantiated, everything else happens automatically and the plot is displayed on the computerscreen as illustrated by any one of the images in Figure 1 or Figure 2 .

Multiple plots

If multiple plots in different formats are needed for a given set of data, all that is required is to instantiate multiple objects of the class named ImgMod29 passing the same data array with different parameters to the constructor for each plot. Be aware, however, that all of the plots willbe produced in a stack in the upper left corner of the screen. You must physically move the plots on the top in order to be able to view the plots lowerdown in the stack.