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Divide

The divide operator is represented by a slash (

) and divides the first operand by the second operand:

var iResult = 66 / 11;

The divide operator, like the multiply operator, has special behaviors for special values:

If the operands are numbers, regular arithmetic division is performed, meaning that two posi-

tives or two negatives equal a positive, whereas operands with different signs yield a negative.

If the result is too high or too low, the result is either

Infinity

or –

Infinity

If either operand is

NaN

, the result is

NaN

Infinity

is divided by

Infinity

, the result is

NaN

Infinity

is divided by any number, the result is

Infinity

Division of a non-infinite number by 0 always equals

NaN

Infinity

is divided by any number other than 0, the result is either

Infinity

or –

Infinity

, depending on the sign of the second operand.

Modulus

The modulus (remainder) operator is represented by a percent sign (

) and is used in the following way:

var iResult = 26 % 5; //equal to 1

Just like the other multiplicative operators, the modulus operator behaves differently for special values:

If the operands are numbers, regular arithmetic division is performed, and the remainder of that

division is returned.

If the dividend is

Infinity

or the divisor is 0, the result is

NaN

Infinity

is divided by

Infinity

, the result is

NaN

If the divisor is an infinite number, the result is the dividend.

If the dividend is 0, the result is 0.

Additive operators

The additive operators, add and subtract, are typically the simplest mathematical operators in program-

ming languages. In ECMAScript, however, a number of special behaviors are associated with each

operator.

Add

The add operator (

) is used just as one would expect:

var iResult = 1 + 2;

ECMAScript Basics

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