# 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]

`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;

`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;

`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

`random()`

[edit]

Generates a pseudo-random number.

var myInt = Math.random();

`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 or functions:

`E:`

Returns the constant e.`PI:`

Returns the value of pi.`LN10:`

Returns the natural logarithm of 10.`LN2:`

Returns the natural logarithm of 2.`SQRT2:`

Returns the square root of 2.