This question already has answers here:
How to convert a String to long in javascript?
(2 answers)
Closed 4 years ago.
I am trying to convert this "9876543210223023" into integer which is received as a string .I have used parseInt but it gets converted into 9876543210223024.
This is causing failure in my validations .
Please suggest how will the value remain same after conversion.
9876543210223023 is > than 9007199254740991, which is Number.MAX_SAFE_INTEGER.
JavaScript has a Number type, which internally is a 64 bit floating point number.
If the range is too big, the machine episilon is too large, and the number is rounded to the nearest representable number, in this case 9876543210223024.
You need a biginteger library, if you want to process numbers of this size.
If your browser is modern enough (aka Chrome/Chromium), it might have the type "BigInteger" already built-in.
In that case: BigInt("9876543210223023", 10)
Otherwise, the linked BigInt-library will act as polyfill.
Related
This question already has answers here:
What is JavaScript's highest integer value that a number can go to without losing precision?
(21 answers)
How to convert a String to long in javascript?
(2 answers)
Closed 10 months ago.
A quick maybe simple question :
We are trying to parse a string into number , the sample number is "1928433000460244141" so when we try to parse it to integer we get 1928433000460244200
const no1 = "1928433000460244141" ;
console.log(parseInt(no1)); // returns 1928433000460244200
what can cause this problem and what is the solution ?
BigInt can be used to store the data , but the problem is we want to send the string converted to number to a service we are using right now , we do not have any access hence it is a 3rd party service so we should handle it from our side.
The MAX_SAFE_INTEGER constant has a value of 9007199254740991 (9,007,199,254,740,991 or ~9 quadrillion). The reasoning behind that number is that JavaScript uses double-precision floating-point format numbers as specified in IEEE 754 and can only safely represent integers between -(2^53 - 1) and 2^53 - 1.
Source
Because your number is larger than the safe integer limit, you're likely experiencing some floating-point precision issues that are rounding the value off.
This question already has an answer here:
What is the standard solution in JavaScript for handling big numbers (BigNum)?
(1 answer)
Closed 6 years ago.
n = "11004691915666669"
parseInt(n)
parseInt(n, 10)
Both results are: 11004691915666668
This is off by one. I tested some other values and they convert correctly. Is this a bug in the library or is there a better way to convert?
See this SO question for more details. Your value is beyond the maximum integer that Javascript can represent with full accuracy.
Under the hood Javascript doesn't understand integers, everything's floating point. You're hitting the reduced accuracy that happens when you get to very large numbers.
From the Javascript reference at MDN given here.
The integer range for a Number is defined as follows :
var biggestInt = 9007199254740992;
var smallestInt = -9007199254740992;
Which is why since your number exceeds the biggestInt value preset by Javascript, the parseInt method only returns the integer value that lies within the Integer range for a Number in Javascript as defined above.
This question already has answers here:
Large numbers erroneously rounded in JavaScript
(6 answers)
Javascript parseInt() with leading zeros
(7 answers)
Closed 7 years ago.
I'm trying to convert a string to number in Javascript, but here is my problem :
var string = "068999999501111443";
parseInt(string); // 68999999501111440
Number(string); // 68999999501111440
Why does this happen and how to fix it ?
Thanks
This is because the number is too large to be stored accurately. It is being stored as a floating point number, which can only store a certain amount of precision. Beyond it's maximum precision, you'll get what look like weird rounding errors.
You'll get similar effects for decimals with a large number of decimal places. This is more well known, as it tends to occur more often, but it's exactly the same effect that is happening here.
This question already has answers here:
Why do JavaScript converts some number values automatically
(5 answers)
Closed 7 years ago.
See snippet:
var num = "9223372036854775808";
document.write(num);
document.write("<br>");
document.write(parseInt(num, 10));
On running the code snippet, the first write yields:
9223372036854775808
and the third write yields:
9223372036854776000
But, I am only parsing the number in string form to number. Why does it give a still larger number?
I thought it might have to do something with limits of storage capacity, but then, why would it yield a larger number if it could not store the smaller?
I read this question: Why parsing a very large number to integer return 1 and the parseInt doc but they did not help much.
So, Why does parsing a large number, of string form, return a larger number?
The first result is fine as it is treated as a string.
In the second one, it crosses the value of int which is +/- 9007199254740992 ie, the maximum value which parseint can parse is 9007199254740992 and since your value 9223372036854775808 is larger than the maximum value. it is giving some garbage value.
As commented correctly by blunderboy it seems that that the reason could be this
The numbers in Javascript are 64 bit "double" precision which follow the IEE754 floating point. Sothe largest positive whole number that can therefore be accurately represented is 2^53 and the rest of the remaining bits are reserved for the exponent.
If you check the ECMA specs this has been explained.
This question already has answers here:
How can I convert numbers into scientific notation?
(3 answers)
Closed 9 years ago.
I have to convert the float to exponential..
0.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000021
Using
parseFloat(result)
Gives 2.1e-87
But
10000000
Gives 10000000 (same) but I like to get 100.0e+3 etc..So I used parseFloat(result).toExponential(3); But the problem here is it is truncating everything ev even if it has more values for example 111222333 it makes it as 111.22+3 so while I reconverting as integer I am cannot get the original value..
Is there any javascript function to achieve this or how can I achieve this..
Thanks in advance..
If you use toExponential() with out the parameter, it will not drop the fractions:
console.log( (111222333).toExponential() ); // "1.11222333e+8"
The parameter specifies the amount of digits after the decimal point. If you drop it, it displays as many digits as needed (wrt to the double precision JavaScript uses internally).