Access Point Declarations

    AccessPoint a1=instr1(0.1,0.5), a2=instr2(centre);
    AccessPoint a3=instr3(left,bottom), a4;

If an access point is to be given an initial value then the familiar access point notation of the instrument name followed by one or two coordinates in parentheses is used. Note that an access point does not need to be initialised, although if you try to apply a device via an access point before it has been initialised nothing will happen.