6.5.1 Basic concepts

BoGLi provides a variety of parameters which allow to change and customise the graphical output as regards primitives like colours, linestyles, character sizes as well as text output and general appearance. These parameters are class attributes of the software for which methods exist to easily set and change values with simple user commands. To get a list of all available parameters and their current settings type show all. To retrieve the current value of a single parameter use parameter ?, where parameter is the parameter name. Example: chLabelX ? will provide the character size of the x-label.

The usual way to set parameter values is to type the parameter name followed by the desired value. Example: chLabelX 0.5 changes the character size of the x-label to a value of 0.5 (in units of 1/40 the height of the view surface). In case the parameter name is followed by no reasonable argument BoA provides an error message. For arguments outside the corresponding scope pgplot uses its intrinsic default values while BoGLi keeps the false value typed in. To use the default value of every parameter provided by BoGLi use default.

Depending on their arguments four kinds of parameters can be distinguished:

(1)

float and integer parameters (see Sect. 6.5.2)

(2)

logical parameters (see Sect. 6.5.5.1)

(3)

string parameters (see Sect. 6.5.5.2)

(4)

list parameters (see Sect. 6.5.5.3).

Float and integer parameters require floating point or integer numbers as arguments, respectively. If a float argument is given where an integer number is expected BoA provides an error message. Logical parameters require 0 or 1 as arguments and serve as switches. Example: box 0 switches off the display of the box(es); to switch it on again use box 1. List parameters contain lists or arrays and have special commands to be changed (e.g. plot channel).