# JavaScript/Numbers

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

## Basic use

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

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

#### `ceil(float)`

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

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

#### `floor(float)`

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)`

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

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

#### `min(int1, int2)`

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

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

#### `random()`

Generates a pseudo-random number.

```var myInt = Math.random();
```

#### `round(float)`

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

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

### Properties

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.