How do you check if a number has a decimal in javascript?
I am looking for an easy way in JavaScript to check if a number has a decimal place in it (in order to determine if it is an integer). For instance, Show
reformed 4,24510 gold badges59 silver badges83 bronze badges asked Feb 20, 2010 at 22:48
Using modulus will work:
Note that this is based on the numerical value of the number, regardless of format. It treats numerical strings containing whole numbers with a fixed decimal point the same as integers:
answered Feb 20, 2010 at 22:50
Andy EAndy E 330k83 gold badges469 silver badges441 bronze badges 19
Number.isInteger() is part of the ES6 standard and not supported in IE11. It returns false for answered Mar 15, 2017 at 2:16
le_mle_m 18.3k9 gold badges61 silver badges74 bronze badges 6 Or you could just use this to find out if it is NOT a decimal:
dYale 1,4531 gold badge16 silver badges19 bronze badges answered Oct 24, 2011 at 15:31
IkeIke 7135 silver badges2 bronze badges 11 Simple, but effective!
answered Mar 2, 2015 at 17:26
dYaledYale 1,4531 gold badge16 silver badges19 bronze badges 3 The most common solution is to strip the integer portion of the number and compare it to zero like so:
answered Feb 20, 2010 at 23:25
ThomasThomas 62.9k11 gold badges93 silver badges139 bronze badges 11 //How about byte-ing it?
I always feel kind of bad for bit operators in javascript- they hardly get any exercise. answered Feb 21, 2010 at 1:15
kennebeckennebec 100k31 gold badges104 silver badges126 bronze badges 2
In JavaScript, isSafeInteger() is a Number method that is used to return a Boolean value indicating whether a value is a safe integer. This means that it is an integer value that can be exactly represented as an IEEE-754 double precision number without rounding. answered Aug 10, 2021 at 12:58
aadityaaaditya 4697 silver badges19 bronze badges 1
answered Sep 3, 2018 at 19:45
4
Pretty cool and works for things like XX.0 too! It works because Math.floor() chops off any decimal if it has one so if the floor is different from the original number we know it is a decimal! And no string conversions :) answered Jun 6, 2017 at 0:41 0
answered Feb 21, 2010 at 0:09
ghostdog74ghostdog74 313k55 gold badges252 silver badges339 bronze badges 3
Sirko 70.5k19 gold badges143 silver badges175 bronze badges answered Oct 26, 2012 at 19:30
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when passed a number,
answered Jan 21, 2015 at 19:05
MichaelMichael 21.4k33 gold badges128 silver badges182 bronze badges 1 convert number string to array, split by decimal point. Then, if the array has only one value, that means no decimal in string.
This way you can also know what the integer and decimal actually are. a more advanced example would be.
answered Jul 3, 2016 at 14:14
KareemKareem 4,65540 silver badges35 bronze badges Use following if value is string (e.g. from
I add answered Mar 26, 2020 at 10:01
michal.jakubeczymichal.jakubeczy 6,8861 gold badge52 silver badges57 bronze badges Here's an excerpt from my guard library (inspired by Effective JavaScript by David Herman):
answered Oct 15, 2015 at 8:16
schirrmacherschirrmacher 2,2812 gold badges27 silver badges29 bronze badges You can multiply it by 10 and then do a "modulo" operation/divison with 10, and check if result of that two operations is zero. Result of that two operations will give you first digit after the decimal point. If result is equal to zero then the number is a whole number.
answered Apr 5, 2017 at 7:48
BSevoBSevo 7435 silver badges13 bronze badges
answered Aug 4, 2017 at 15:34
Steve BrushSteve Brush 2,7311 gold badge21 silver badges15 bronze badges You can use the bitwise operations that do not change the value (
answered Feb 23, 2018 at 16:19
makovkastarmakovkastar 4,9602 gold badges29 silver badges49 bronze badges
answered Apr 1, 2019 at 13:52
Perhaps this works for you? It uses regex to check if there is a comma in the number, and if there is not, then it will add the comma and stripe.
answered Jun 6, 2019 at 11:09
3 When using counters with decimal steps, checking if number is round will actually fail, as shown below. So it might be safest (although slow) to format the number with 9 (could be more) decimal places, and if it ends with 9 zeros, then it's a whole number.
answered Jun 7, 2021 at 16:50
Function for check number is Decimal or whole number
Tom Sabel 3,76632 silver badges44 bronze badges answered Apr 28, 2016 at 6:56
How do you check if a number is a decimal or not?You can multiply it by 10 and then do a "modulo" operation/divison with 10, and check if result of that two operations is zero. Result of that two operations will give you first digit after the decimal point. If result is equal to zero then the number is a whole number.
How do you check if a string has a decimal?Python String isdecimal() Method
The isdecimal() method returns TRUE if the string is nonempty and all characters in it are decimal characters. Otherwise, it returns FALSE.
How do you display decimals in JavaScript?Use the toFixed() method to format a number to 2 decimal places, e.g. num. toFixed(2) . The toFixed method takes a parameter, representing how many digits should appear after the decimal and returns the result.
How do you check if number is a whole number in JS?The Number. isInteger() method in JavaScript is used to check whether the value passed to it is an integer or not. It returns true if the passed value is an integer, otherwise, it returns false.
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