This question already has answers here:
How to avoid scientific notation for large numbers in JavaScript?
(27 answers)
Closed 6 years ago.
I try to get
Math.pow(2,1000);
The result is " 1.2676506002282294e+30 "
I need the number without Euler's number "e+30"
That's scientific notation, not Euler's number.
If you want to show the number without the e+NN part:
convert it to a string
parse the e+NN part
shift the decimal place the appropriate number of digits
return the output as a string
be aware that doing so will lead to inaccurate values for some calculations due to how floating point arithmetic works.
With very large numbers, JavaScript displays them in scientific notation. This is because it is very expensive and unreadable to list them.
For your example, it basically means
1.2676506002282294 * 10 ^ 30
You take the number and then multiply it by 10 to the 30th power.
Calculators often use "E" or "e" like this: 1.8004E+94
6E+5 is the same as 6 × 10^5
To get it without this notation, simply use smaller numbers as the exponent.
Example: Math.pow(2,10)
Mathisfun provides an excellent article on scientific notation. Check it out here
https://www.mathsisfun.com/numbers/scientific-notation.html
Euler's number is a constant that is the base of a natural number. It's an irrational number, meaning its digits go on forever. The first couple digits are 2.7182818284
Related
This question already has answers here:
What is the equivalent of NumberFormat in JavaScript or JQuery?
(5 answers)
Closed 7 years ago.
I know there have been many threads on this topic but none seem to answer my question directly. I want to convert a number to two decimal places no matter the length. So 0.5 should turn into 0.50, and 5.3145 should go to 5.31. Most importantly, I also need to keep the number as a number datatype. I know toFixed(2) will create two decimal places, but this also turns the number into a string. If I wrap the toFixed(2) with a parseInt function (e.g. parseInt(amount.toFixed(2))) then 0.5 seems to be converted to "0.50", and then back to 0.5 with out the trailing zero. Adding a second layer of parentheses doesn't solve the problem either. Any ideas?? Thank you in advance!
What you want to do is impossible to do. Numbers do not have trailing zeros. There are no significant digits. So when you need the trailing zero, you need to convert it to a string with toFixed().
You don't need trailing zeros for mathematical computations - so if you are just looking to display it - keep it a string and use the toFixed(2) then when you need to do computations on it - convert with parseFloat
This question already has answers here:
What is JavaScript's highest integer value that a number can go to without losing precision?
(21 answers)
Closed 8 years ago.
Type this in the console of your browser:
9999999999999999==10000000000000000
It says they are equal, why?
JavaScript only supports 53 bit integers
All numbers in JavaScript are floating point which means that integers are always represented as
sign × mantissa × 2exponent
The mantissa has 53 bits. You can use the exponent to get higher integers, but then they won’t be contiguous, any more. For example, you generally need to multiply the mantissa by two (exponent 1) in order to reach the 54th bit. However, if you multiply by two, you will only be able to represent every second integer:
This question already has answers here:
What is JavaScript's highest integer value that a number can go to without losing precision?
(21 answers)
Closed 8 years ago.
Can anybody solve the following problem with javascript
var i = 10152233307863175;
alert(i.toString());
alert shows value 10152233307863176. Any solution. Problem is when I get json object on client and when string is converted to json it contains wrong values.
This is a limitation in the precision of the numeric data format that javascript uses (double precision floating point).
The best way of storing that value, assuming you don't need to do any mathematical operations, is storing it as a string in the first place.
MDN has this to say about numbers in JavaScript.
Numbers in JavaScript are "double-precision 64-bit format IEEE 754 values", according to the spec.
There is no real integers in JavaScript. According to this source:
ECMAScript numbers are represented in binary as IEEE-754 (IEC 559) Doubles, with a resolution of 53 bits, giving an accuracy of 15-16 decimal digits; integers up to just over 9e15 are precise, ...
Your number 10152233307863175 contains 17 digits. Since the number is represented as a floating point number, JavaScript tries to do it's best and set bits in a way that the resulting number is closest to the supplied number.
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 9 years ago.
I want to make multiplication using JavaScript.
Multiplication of 2 and 0.15 is 0.3 but 3 and 0.15 is 0.44999999999999996. I want to get 0.45 such as result. How can I do it with JavaScript?
It's a rounding error. You may want to round your number to a fixed amount of digits, like this:
parseFloat((your_number).toFixed(2));
Unfortunately this happens in any language using floating point arithmetic. It's an artifact arising when floating point operations are encoded into binary, operations performed, and decoded from binary to report the answer in a form you'd expect.
Depending on what you want to do with the output, you can call a round()-like function to round to a number of decimal places or compare the output to a value using a (small) number called a tolerance. E.g. two numbers are considered equal if their absolute difference is less than this tolerance.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Large numbers erroneously rounded in Javascript
I am experiencing some strange behavior when working with numbers in javascript. When I use the following code:
CLICK HERE
I get the number 9200000000032336 in my console. I think it most be something with rounding or max values for numbers, but I don't understand it completely. Anyone?
I'm not a Javascript expert, but it sounds like your number is being stored as an IEEE-754 64-bit floating point number. Certainly that's what I get from C# code which will display the exact value of a double:
double d = 9200000000032337;
Console.WriteLine(DoubleConverter.ToExactString(d));
(Using my own DoubleConverter class.) My output is the same as yours: 9200000000032336
Floating point values only ever hold a certain number of significant digits accurately - and when the numbers get high enough, even integers can't be stored exactly.
ECMA-262 seems to confirm this:
4.3.19
Number value
primitive value corresponding to a double-precision 64-bit binary format IEEE 754 value
and from section 7.8.3 (numeric literals):
A numeric literal stands for a value of the Number type. This value is determined in two steps: first, a
mathematical value (MV) is derived from the literal; second, this mathematical value is rounded as described
below.
Section 8.5 contains more details.