Datasheet

Chapter 1: A Quick Introduction to Programming

Operators and Operator Precedence

An operator acts on one or more operands when comparing, assigning, concatenating, calculating, and

performing logical operations. Say you want to calculate the difference between two variables

X and Y

and save the result in variable

Z . These variables are the operands and to find the difference you use the

subtraction operator like this:

Z = X - Y

Here you use the assignment operator ( = ) to assign the difference between X and Y , which was found by

using the subtraction operator (

- ).

Operators are one of the single-most important parts of any programming language. Without them, you

cannot assign values to variables or perform calculations or comparisons. In fact, you can’t do much at all.

There are different types of operators and they each serve a specific purpose, as shown in the

following table.

Operator Purpose

assignment ( = ) The most obvious and is simply used for assigning a value to a variable or

property.

arithmetic These are all used to calculate a numeric value, and are normally used in

conjunction with the assignment operator and/or one of the comparison

operators.

concatenation These are used to concatenate (“join together”) two or more different

expressions.

comparison These are used for comparing variables and expressions against other

variables, constants, or expressions.

logical These are used for performing logical operations on expressions; all logical

operators can also be used as bitwise operators.

bitwise These are used for comparing binary values bit by bit; all bitwise operators

can also be used as logical operators.

Figure 1-7

Figure 1-7 shows the final summary message generated by the code. Notice how well the information is

integrated.

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