With this command, constants and new variables can be defined.
New variables are defined by combining existing variables through the following operations:
( ) + - * / ^ **
and intrinsic functions
abs acos acosd asin asind atan atand cos cosd cosh deg exp log log10 rad sin sind sinh sqrt tan tand tanh
The definition string should look like, NEW : operation(OLD1,OLD2). Notice the assignment with ':'.
Constants are defined by a string like, PI=3.142 . Notice the assignment with '='.