Circles are defined using the command circle :
- funct -> circle C
creates a circle whose name is C. A circle is defined by its center and its radius. The default parameters for a circle are (0,0) for the center and 1 for the radius. The command coord can then be used to change them :
- funct -> coord C A 0.7
will make A the center of C and 0.7 its radius. Of course A must have been defined before the preceeding command. Instead of 0.7 we could put a numerical expression understood by the expression evaluator.
In the definition of a circle only the coordinates of its center are kept : it is possible to destroy the point A and the center of C will not be changed.
The command show is used to print the coordinates of a circle :
- funct -> show C
will print something like this
x = 1 y = -1 R = 0.7
meaning that the center of C is the point of coordinates (1,-1) and its radius is 0.7. After this command the variables center_x and center_y will contain the coordinates of the center and Radius the radius.