Math Operators

 Format of assignment statement

An expression is a combination of variables/property values/constants called operands separated by operators.

Operators are symbols used to tell the computer what to do.

There are several different types of operators

• Arithmetic - Used to do calculations
• Concatenation - Used to put strings together
• Relational - Used in comparisons
• Logical - Also used in comparisons

Simple Arithmetic operators

^     Exponentiation   (Binary operator - applied to two operands)

-     Negation            (Unary operator - applied to one operand)

*    Multiplication    (Binary operator)

/    Division     (Binary operator)

\    Integer Division     (Binary operator)

Mod    Modulus Division     (Binary operator)

+    Addition     (Binary operator)

-    Subtraction     (Binary operator)

As you can see there are three different division operators.

• Regular division 11 / 2 = 5.5 returns a floating point (with decimals) answer
• Integer division 11 \ 2 = 5 returns a whole number, discarding the remainder
• Modulus division 11 Mod 2 = 1 returns only the remainder 

• Note: The Integer Division  operator ( \ ) only work with integral type data (Short, Integer and Long).  If you use floating point values they will be rounded to integers before the division takes place.

The following are examples of expressions

• decRadius^2
• -intyardage
• decAmount * decSalesTaxRate
• intTotal / intCount
• decAmount + decSalesTax
• decAmount - decDiscount
• intCandyBars \ intNumPeople
• intCandyBars Mod intNumPeople

We can combine multiple operators and operands in one expression

What is the result of the following expression?

decAnswer = 6 – 3 * 6 / 9

Click for Answer

The computer evaluates expression based on a set of rule called the hierarchy of operations or order of precedence which is the same order of precedence you learned in math class. We can alter the order of precedence by using parenthesis

 decAnswer = (6 – 3) * (6 / 9)

Order of Precedence

• all operations in parenthesis
• exponentiation
• multiplication and division (as they occur from left to right)
• integer division
• modulus division
• addition and subtraction (as they occur from left to right)