# JavaScript/Numbers

JavaScript implement numbers as floating point values, that is, they're attaining decimal values as well as whole number values.

## Contents

## Basic Use[edit]

To make a new number, a simple initialization suffices:

var foo = 0; // or whatever number you want

After you have made your number, you can then modify it as necessary. Numbers can be modified or assigned using the operators defined within JavaScript.

foo = 1; //foo = 1 foo += 2; //foo = 3 (the two gets added on) foo -= 2; //foo = 1 (the two gets removed)

Number literals define the number value. In particular:

- They appear as a set of digits of varying length.
- Negative literal numbers have a minus sign before the set of digits.
- Floating point literal numbers contain one decimal point, and may optionally use the E notation with the character e.
- An integer literal may be prepended with "0", to indicate that a number is in base-8. (8 and 9 are not octal digits, and if found, cause the integer to be read in the normal base-10).
- An integer literal may also be found with prefixed "0x", to indicate a hexadecimal number.

## The Math Object[edit]

Unlike strings, arrays, and dates, the numbers aren't objects, so they don't contain any methods that can be accessed by the normal dot notation. Instead a certain Math object provides usual numeric functions and constants as methods and properties. The methods and properties of the Math object are referenced using the *dot operator* in the usual way, for example:

var varOne = Math.ceil(8.5); var varPi = Math.PI; var sqrt3 = Math.sqrt(3);

### Methods[edit]

#### random()[edit]

Generates a pseudo-random number.

var myInt = Math.random();

#### max(int1, int2)[edit]

Returns the highest number from the two numbers passed as arguments.

var myInt = Math.max(8, 9); document.write(myInt); //9

#### min(int1, int2)[edit]

Returns the lowest number from the two numbers passed as arguments.

var myInt = Math.min(8, 9); document.write(myInt); //8

#### floor(float)[edit]

Returns the greatest integer less than the number passed as an argument.

var myInt = Math.floor(90.8); document.write(myInt); //90;

#### ceil(float)[edit]

Returns the least integer greater than the number passed as an argument.

var myInt = Math.ceil(90.8); document.write(myInt); //91;

#### round(float)[edit]

Returns the closest integer to the number passed as an argument.

var myInt = Math.round(90.8); document.write(myInt); //91;

### Properties[edit]

Properties of the Math Object are most commonly used constants.

**PI:**Returns the value of pi.**E:**Returns the constant e.**SQRT2:**Returns the square root of 2.**LN10:**Returns the natural logarithm of 10.**LN2:**Returns the natural logarithm of 2.