Convert number to float javascript

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I've got an integer (e.g. 12), and I want to convert it to a floating point number, with a specified number of decimal places.

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How do I turn a number into a float?
How parseFloat () works in JavaScript?
How do I cast a float in JavaScript?
Can integer convert to float?

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function intToFloat(num, decimal) { [code goes here] }
intToFloat(12, 1) // returns 12.0
intToFloat(12, 2) // returns 12.00
// and so on…

mskfisher

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asked Nov 27, 2010 at 18:36

0

What you have is already a floating point number, they're all 64-bit floating point numbers in JavaScript.

To get decimal places when rendering it (as a string, for output), use .toFixed(), like this:

function intToFloat(num, decPlaces) { return num.toFixed(decPlaces); }

You can test it out here (though I'd rename the function, given it's not an accurate description).

answered Nov 27, 2010 at 18:41

Nick CraverNick Craver

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6

toFixed(x) isn't crossed browser solution. Full solution is following:

function intToFloat(num, decPlaces) { return num + '.' + Array(decPlaces + 1).join('0'); }

answered Jul 28, 2014 at 13:54

Simon BorskySimon Borsky

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3

If you don't need (or not sure about) fixed number of decimal places, you can just use

xAsString = (Number.isInteger(x)) ? (x + ".0") : (x.toString());

This is relevant in those contexts like, you have an x as 7.0 but x.toString() will give you "7" and you need the string as "7.0". If the x happens to be a float value like say 7.1 or 7.233 then the string should also be "7.1" or "7.233" respectively.

Without using Number.isInteger() :

xAsString = (x % 1 === 0) ? (x + ".0") : (x.toString());

answered Jan 22, 2018 at 12:28

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Below is the example of the parseFloat() function.

Example:
javascript
<script>
    var v2 = parseFloat("3.14");
    document.write('Using parseFloat("3.14") = '
    + v2 + "<br>");
</script>
Output:
```
Using parseFloat("3.14") = 3.14
```

The parseFloat() function is used to accept the string and convert it into a floating-point number. If the string does not contain a numeral value or If the first character of the string is not a Number then it returns NaN i.e, not a number. It actually returns a floating-point number parsed up to that point where it encounters a character that is not a Number.

Syntax:

parseFloat(Value)

Parameters: This function accept a single parameter as mentioned above and described below:

value This parameter obtains a string which is converted to a floating-point number.

Return value: It returns a floating-point Number and if the first character of a string cannot be converted to a number then the function returns NaN i.e, not a number.

Below examples illustrate the parseFloat() function in JavaScript:

Example 1: The parseFloat() function ignores leading and trailing spaces and returns the floating point Number of the string.

Input : var n = parseFloat("  2018  ");
Output: n=2018 (floating point Number)

Example 2:

Input: var a = parseFloat("1000.04");
Output:now a = 1000.04(floating point Number)

More example codes for the above function are as follows:

Program 1:

javascript

<!DOCTYPE html>

<html>

<body>

<script>

a = parseFloat(" 100 ")

document.write('parseFloat(" 100 ") = ' +a +"<br>");

b = parseFloat("2018@geeksforgeeks")

document.write('parseFloat("2018@geeksforgeeks") = '

+b +"<br>");

c = parseFloat("geeksforgeeks@2018")

document.write('parseFloat("geeksforgeeks@2018") = '

+c +"<br>");

d = parseFloat("3.14")

document.write('parseFloat("3.14") = '

+d +"<br>");

e = parseFloat("22 7 2018")

document.write('parseFloat("22 7 2018") = '

+e +"<br>");

</script>

</body>

</html>

Output:

parseFloat(" 100 ") = 100
parseFloat("2018@geeksforgeeks") = 2018
parseFloat("geeksforgeeks@2018") = NaN
parseFloat("3.14") = 3.14
parseFloat("22 7 2018") = 22

Program 2: Using isNaN() function to test that converted values are valid number or not.

javascript

<!DOCTYPE html>

<html>

<body>

<script>

var x = parseFloat("3.14");

if (isNaN(x))

document.write("x is not a number" + "<br>");

else

document.write("x is a number" + "<br>");

var y = parseFloat("geeksforgeeks");

if (isNaN(y))

document.write("y is not a number" + "<br>");

else

document.write("y is a number" + "<br>");

var v1 = parseInt("3.14");

var v2 = parseFloat("3.14");

document.write('Using parseInt("3.14") = '

+ v1 + "<br>");

document.write('Using parseFloat("3.14") = '

+ v2 + "<br>");

</script>

</body>

</html>

Output:

x is a number
y is not a number
Using parseInt("3.14") = 3
Using parseFloat("3.14") = 3.14

Supported Browsers:

Google Chrome 1 and above
Edge 12 and above
Firefox 1 and above
Internet Explorer 3 and above
Safari 1 and above
Opera 3 and above

How do I turn a number into a float?

Converting Integers to Floats.

Python's method float() will convert integers to floats. To use this function, add an integer inside of the parentheses:.

In this case, 57 will be converted to 57.0 ..

You can also use this with a variable. ... .

By using the float() function, we can convert integers to floats..

How parseFloat () works in JavaScript?

The parseFloat() function is used to accept the string and convert it into a floating-point number. If the string does not contain a numeral value or If the first character of the string is not a Number then it returns NaN i.e, not a number.

How do I cast a float in JavaScript?

To convert string to float, you can use the “Type Conversion” JavaScript feature or the “parseFloat()” method. Type conversion utilizes the Unary operator “+” for converting string value to float, whereas the “parseFloat()” method accepts a string “value” as an argument and returns the converted float number.

Can integer convert to float?

To convert an integer data type to float you can wrap the integer with float64() or float32. Explanation: Firstly we declare a variable x of type int64 with a value of 5. Then we wrap x with float64(), which converts the integer 5 to float value of 5.00.

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