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# JavaScript Number Methods

## Global Methods

JavaScript worldwide capacities can be utilized on all JavaScript information types.

These are the most significant techniques, when working with numbers:

Method Description
Number() Returns a number, changed over from its argument.
parseFloat() Parses its contention and returns a gliding point number
parseInt() Parses its contention and returns an integer

## Number Methods

JavaScript number strategies are techniques that can be utilized on numbers:

Method Description
toString() Returns a number as a string
toExponential() Returns a string, with a number adjusted and composed utilizing exponential notation.
toFixed() Returns a string, with a number adjusted and composed with a predefined number of decimals.
toPrecision() Returns a string, with a number composed with a predefined length
valueOf() Returns a number as a number

## The toString() Method

toString() restores a number as a string.

All number strategies can be utilized on a numbers (literals, factors, or expressions):

### Example

var x = 123;
x.toString();           /returns 123 from variable x
(123).toString();       /returns 123 from exacting 123
(100 + 23).toString();  /returns 123 from articulation 100 + 23
Try it Yourself »

## The toExponential() Method

toExponential() restores a string, with a number adjusted and composed utilizing exponential notation.

A parameter characterizes the quantity of characters behind the decimal point:

### Example

var x = 9.656;
x.toExponential(2);    /returns 9.66e+0
x.toExponential(4);    /returns 9.6560e+0
x.toExponential(6);    /returns 9.656000e+0
Try it yourself »

The parameter is discretionary. In the event that you don't indicate it, JavaScript won't round the number.

## The toFixed() Method

toFixed() restores a string, with the number composed with a predefined number of decimals:

### Example

var x = 9.656;
x.toFixed(0);          /returns 10
x.toFixed(2);          /returns 9.66
x.toFixed(4);          /returns 9.6560
x.toFixed(6);          /returns 9.656000
Try it yourself »

## The toPrecision() Method

toPrecision() restores a string, with a number composed with a determined length:

### Example

var x = 9.656;
x.toPrecision();        //returns 9.656
x.toPrecision(2);       //returns 9.7
x.toPrecision(4);       //returns 9.656
x.toPrecision(6);       //returns 9.65600
Try it Yourself »

## Converting Variables to Numbers

There are 3 JavaScript capacities that can be utilized to change over factors to numbers:

• The Number() method
• The parseInt() method
• The parseFloat() method

These techniques are not number strategies, however global JavaScript methods.

## The Number() Method

Number(), can be utilized to change over JavaScript factors to numbers:

### Example

x = true;
Number(x);        //returns 1
x = false;
Number(x);        //returns 0
x = new Date();
Number(x);        //returns 1404568027739
x = "10"
Number(x);        //returns 10
x = "10 20"
Number(x);        //returns NaN
Try it Yourself »

## The parseInt() Method

parseInt() parses a string and returns an entire number. Spaces are permitted. Just the primary number is returned:

### Example

parseInt("10");        /returns 10
parseInt("10.33");     /returns 10
parseInt("10 20 30");  /returns 10
parseInt("10 years");  /returns 10
parseInt("years 10");  /returns NaN
Try it yourself »

If the number can't be changed over, NaN (Not a Number) is returned.

## The parseFloat() Method

parseFloat() parses a string and returns a number. Spaces are permitted. Just the primary number is returned:

### Example

parseFloat("10");       /returns 10
parseFloat("10.33");     //returns 10.33
parseFloat("10 20 30");  //returns 10
parseFloat("10 years");  //returns 10
parseFloat("years 10");  //returns NaN
Try it yourself »

If the number can't be changed over, NaN (Not a Number) is returned.

## The valueOf() Method

valueOf() restores a number as a number.

### Example

var x = 123;
x.valueOf();           /returns 123 from variable x
(123).valueOf();       /returns 123 from strict 123
(100 + 23).valueOf();  /returns 123 from articulation 100 + 23
Try it Yourself »

In JavaScript, a number can be a crude esteem (typeof = number) or an object (typeof = object).

The valueOf() strategy is utilized inside in JavaScript to change over Number items to crude values.

There is no motivation to utilize it in your code.

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