What way i can convert string with 16 digits and 2 fraction value to number ?
Currently when I try to convert Number('1234567890123456.12') will became to 1234567890123456. fraction values will be gone.
I just want to confirm without using any third party lib can i convert this string to number ?
Unfortunately not. Javascript represents it's numbers using double precision floating point numbers. At 16 digits, it will only be able to store the integer component and not the part after the decimal point. You will need a bignum library to use this value.
EDIT: for reference the biggest integer you can use in JavaScript is 9,007,199,254,740,991
EDIT2: Thanks to Jeremy you can use a library like bignumberJS.
Your number has too many algorisms, I've created an example that simulates in the first position of the array the maximum length possible in javascript.
var nums = [
"12345678910111.12",
"1.5323",
"-42.7789"
];
nums.forEach(function(n) {
console.log(parseFloat(n).toFixed(2));
});
https://jsfiddle.net/7zzz1qzt/
I have faced issue to convert 18 digit string number to number. It is convert all digit to 0 after 16 digit. I have apply below code. it is working fine for me.
[{"id":${id},"name":"${name}"}]
Related
I am trying to convert a string with more than 16 digit to number. But in javascript it is not allowed according to various article I read. Reference of some are here
How to convert a long string (more than 16 digits) into numbers
facing an issue with parseFloat when input is more than 16 digits
https://2ality.com/2012/07/large-integers.html
Below is the code I tried.
let x= "123456789123456789"
console.log(parseInt(x))
console.log(parseFloat(x))
console.log(Number(x))
console.log(+x)
let y= "1234567891234567.34"
console.log(parseInt(y))
console.log(parseFloat(y))
console.log(Number(y))
console.log(+y)
I want the exact numbers as I use string to display in ContentEditable field and when I save the data I need to pass it as a number. As it is related to banking the same numbers are important.
Is there any way I can solve this issue or any library I can use to solve this problem
try Use the BigInt, multiply with number or add,minus float number.
let x= "123456789123456789";
console.log(BigInt(x));
console.log(1*x);
let y= "1234567891234567.34";
console.log(0.01-0.01+y);
https://dev.to/sanchithasr/7-ways-to-convert-a-string-to-number-in-javascript-4l
I've seen multiple topics regarding this question, but none seem to answer it.
I want to round a number to two decimals, but without losing the function to use it in equations. So it shouldn't be transformed to a string. This DOES NOT work for what I want: parseFloat("50").toFixed(2)
Does anyone know how to parseFloat with 2 decimals as a number?
Just parse it back to a float.
parseFloat(Number(1.2345).toFixed(2)); //1.23
In javascript a number cannot have trailing zeros. 2.5 is a correct but 2.50 is not, this is why toFixed returns a string, not a number.
The best way to handle what you need is to store the number as a number and let it round out to whatever it needs. Only when showing the number on the screen should you do the toFixed(2) method to transforms it into a string.
// js
const price = 7.999999
const reducedPrice = price * 0.8
const finalReductionPrice = reducedPrice / 2.666666
// html
<p>price {price.toFixed(2)</p>
<p>reducedPrice {reducedPrice.toFixed(2)</p>
<p>finalReductionPrice {finalReductionPrice.toFixed(2)</p>
I'm looking to add decimals to the end of my integer. As an example:
15 => 15.00
The problem with methods like toFixed is that it will convert it into a string. I've tried to use parseFloat() and Number() on the string, but it'll convert it back to an integer with no decimals.
Is this possible? If not, can someone explain to me the logic behind why this isn't possible?
EDIT: Welp the intent was to display the number as a number, but from the going consensus, it looks like the way the only way to go about it is to use a string. Found an answer on the why: https://stackoverflow.com/a/17811916/8869701
The problem you are finding is that all numbers in javascript are floats.
a = 0.1
typeof a # "number"
b = 1
typeof b # number
They are the same.
So there is no real way to convert to from an integer to a float.
This is the reason that all of the parseFloat etc are string methods for reading and writing numbers from strings. Even if you did have floats and integers, specifying the precision of a number only really makes sense when you are displaying it to a user, and for this purpose it will be converted to a string anyway.
Depending on your exact use case you will need to use strings if you want to display with a defined precision.
When working with numbers 15 and 15.00 are equal. It wouldn't make any sense to use memory to store those trailing or leading zeros.
If that information is needed it is usually for displaying purposes. In that case a string is the right choice.
In case you need that value again you can parse the string as a number.
My problem is really simple but I'm not sure if there's a "native" solution using JSON.parse.
I receive this string from an API :
{ "key" : -922271061845347495 }
When I'm using JSON.parse on this string, it turns into this object:
{ "key" : -922271061845347500 }
As you can see, the parsing stops when the number is too long (you can check this behavior here). It has only 15 exact digits, the last one is rounded and those after are set to 0. Is there a "native" solution to keep the exact value ? (it's an ID so I can't round it)
I know I can use regex to solve this problem but I'd prefer to use a "native" method if it exists.
Your assumption that the parsing stops after certain digits is incorrect.
It says here:
In JavaScript all numbers are floating-point numbers. JavaScript uses
the standard 8 byte IEEE floating-point numeric format, which means
the range is from:
±1.7976931348623157 x 10308 - very large, and ±5 x 10-324 - very small.
As JavaScript uses floating-point numbers the accuracy is only assured
for integers between: -9007199254740992 (-253) and 9007199254740992
(253)
You number lies outside the "accurate" range hence it is converted to the nearest representation of the JavaScript number. Any attempt to evaluate this number (using JSON.parse, eval, parseInt) will cause data loss. I therefore recommend that you pass the key as a string. If you do not control the API, file a feature request.
The number is too big to be parsed correctly.
One solution is:
Preprocessing your string from API to convert it into string before parsing.
Preform normal parsing
Optionally, you could convert it back into number for your own purpose.
Here is the RegExp to convert all numbers in your string (proceeded with :) into strings:
// convert all number fields into strings to maintain precision
// : 922271061845347495, => : "922271061845347495",
stringFromApi = stringFromApi.replace(/:\s*(-?\d+),/g, ': "$1",');
Regex explanation:
\s* any number of spaces
-? one or zero '-' symbols (negative number support)
\d+ one or more digits
(...) will be put in the $1 variable
I set up a system that parses a compact data string into JSON. I'm using a 19 digit number to store ids. Unfortunately any number greater than 17 digits, parseFloat() rounds the last few digits.
This breaks the whole data string. Can I fix this?
For example 8246295522085275215 gets turned into 8246295522085276000. Why is this?
http://jsfiddle.net/RobertWHurst/mhZ7Q/
JavaScript has only one numeric type, which is an IEEE 754 double precision floating-point. That means, you have a maximum of 52 bits of precision, which is a bit more than 15 decimal places.
If you need more precision than that, you have to use a bignum library or work with strings.
Numbers in JavaScript lose precision if they are higher than a certain value.
According to http://www.hunlock.com/blogs/The_Complete_Javascript_Number_Reference, integers are only reliable up to 15 digits (9 * 10^15 to be exact).
Try one of these
1. Use a string
2. Split your number in two and save the smaller parts to an array
3. Bignum library
4. Use a smaller number if you can