12.3.2                    Operators and logical conditions

The following operators are available for use in UDO scripts:

++ increment,

--decrement,

~change sign,

+addition,

- subtraction,

*multiplication,

/ division,

^power,

(  )parenthesis,

; instruction delimiter,

, arguments separator,

=substitution,

@string concatenation.

The following logical conditions are available for use in UDO scripts:

&&logical and,

||  logical or,

==equal to,

!=different than,

< less than,

> greater than,

<=   =<    less or equal to,

>=   =>    greater or equal to.

@ - string concatenation

Note that string concatenation allows definition of quasi-arrays. For example we can introduce a set of variables a1,a2,a3… using expressions  a@i, where i is an index variable. However to avoid confusion between a string ai and a variable ai the following rules need to be respected:

·       Let us assume that the index variable i has already been declared and we want to declare a set of variables ai. In such a case we should use the instruction:

(a@i)=……..   Note that the parenthesis is indispensable here.   

·       When the variable a@i is already defined and we want to apply it:

- with a particular value of the index we simply write a1, a2  etc.

- with a general index i we need to use the function VAR(a@i).

Go to next Mathematical functions chapter.

Back to Syntax of the User Defined Object (UDO) language chapter.