New Style

Click the Add to list button on the Custom Function tab of the 2D Custom Function Plots dialog box to display the New Style dialog box, which is used to specify a name for the function you want to add to the function list.

Style name. Type a name for the new function in this field.

OK
Click OK once you have specified a name for the function. You will then be able to define the function using the options on the Custom Function tab.
Cancel
Click Cancel to exit the dialog box without specifying a name (or creating a new function/style).