Custom Function (Ternary Plots)

These options are available in the Custom Function dialog box and via the Graph Options dialog box.

These options can be used to modify or delete an existing custom function or add a new one to the current ternary plot. Note that unlike in 2D Custom Functions, only one function at a time can be shown in a ternary plot (although more than one can be specified). Several options are available for specifying a custom function, either from the list of predefined functions or by defining your own function. For a detailed discussion of common statistical models applicable to ternary plots, refer to the topics on mixture models in the context of Experimental Design.  

Function/Add new function/Delete

Click the Function drop-down box to display a list of functions from which you can choose the function you want to edit. If you want to create a new function, click the Add new function button; a new number will be assigned to this function and displayed in the Function field. To delete an existing function, specify the function number in the Function field and then click the Delete button.

Display

Select the Display check box to display the surface specified by the current custom function. Note that only one surface can be displayed at a time in a 3D or ternary plot.

Display contour/Display surface (one only)

Select the Display contour or Display surface check box to display either the contour lines or surface area on your plot.

Surface specs

Click the Surface specs button to display the Surface Specifications dialog box, which provides full control of the colors, shading, and other surface and contour line properties of your graph.

V(x,y, z) =

Type in the function you want to plot in the V(x,y, z) = box. Note that if you have selected the Function guide check box, a menu with possible characters or functions will be displayed as you type. You can choose a predefined function or type the function yourself using the appropriate characters from this menu. If you want to save this function for later use, you must add it to the function list in the Function Name Manager dialog box that can be opened by clicking the Function List button (see below).

Function guide

Select the Function guide check box for guidance when you are entering a formula into the V(x,y,z)= box. If this check box is selected, then every time you type a letter to begin a new word (i.e. type a letter after the equal sign or after a space), the list of available STATISTICA functions that start with that letter will be displayed. You can select from this list (by double-clicking on the function name) to enter the selected function.

Add to list

Click the Add to list button to create a function that can be saved and reused at a later time. The Custom Function Name dialog box will be displayed, in which you can specify a name for the function you want to save. For subsequent use, the function listed with this name can be selected from the Function Name Manager (see Function List below).

Function list

Click the Function list button to display the Function Name Manager, which is used to create a new function and to edit, rename, or delete an existing function.

Style

As all other features and aspects of graphs, the specifications for the custom fit surface can be saved in a Graphics Style using the Style box. In that case, the saved style will primarily contain any customizations you might have made in the Surface Specifications dialog box. To view a menu of options related to styles (Save, Save As, Revert to unmodified, etc.), click the button to the right of this box. See Graphics Styles for additional details.