This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 9 years ago.
test there in their consoles browser
1067.11-1000 = 67.1099999999999
but the correct thing 67.11
can even test the calculator windows ..
could someone explain this to me?
Floating point numbers are stored using base2, this creates small differences like the one you demonstrate above when converting to base10. The difference will be even greater if use the following numbers: 1000000067.11 - 1000000000 = 67.1100000143. This is because the level of precision decreases as the numbers calculated increases.
Lack of precision is the main disadvantage of the float type numbers - some real numbers can only be represented approximately.
You can follow this link to learn more about representation of floating point format
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This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 4 years ago.
Hi I am doing following operation in Javascript and I am getting weird results, can someone tell me what is going on.
5.62-6.18+0.56 = 4.440892098500626e-16
Because of floating point inaccuracies, the result isn't exactly zero. JavaScript uses scientific notation to display numbers as small as this one. You might be interested in the toPrecision() method.
This question already has answers here:
Is floating point math broken?
(31 answers)
Closed 5 years ago.
Can anyone answer me why javascript adds up 1.123460 + 0.112210 as 1.2356699999999998
while no way I can come up with that result by manual calculation or by any other compilers..
Am I going crazy or javascript, cannot figure out
Its just how JavaScript and many other languages deal with floats. Rounding them to 15 decimal places. Check this How to deal with floating point number precision in JavaScript? How to deal with floating point number precision in JavaScript?
This question already has answers here:
How to deal with floating point number precision in JavaScript?
(47 answers)
Closed 6 years ago.
I am trying to use eval() for calculator i am making, but if when i try this
console.log(eval("5.2-5"));
It returns
0.20000000000000018
Why is this happening.Thank you for your time.
This is due to how Javascript handles floating point precision. Please see How to deal with floating point number precision in JavaScript? for more information
Short answer: Due to the nature of how computers process floats, this means floating point accuracy actually breaks down past a certain point. This is what you're seeing.
Javascript evaluates "5.2-2" to a floating point number, which precision is not guaranteed.
If you need a fixed precision you could use
console.log(eval("5.2-5.0").toFixed(2)):
This question already has answers here:
Large numbers erroneously rounded in JavaScript
(6 answers)
Closed 8 years ago.
I have this number in javascript - 1234567890123456789
This number is apparently a magical number, because when interpreted the lowest two digits magically turn into zeros!!!!!!! Run it through the console and you get this: 1234567890123456800
But wait - theres more. try out this number: 12345678901234568999
Console outputs 12345678901234570000
What is going on here? Have I finally lost my mind or is this some sort of cosmic joke?
Numbers in JavaScript are floating point numbers. As such, integers/numbers above a certain value are prone to precision errors, as you have experienced first hand.
Any number larger than Number.MAX_SAFE_INTEGER, or 9007199254740991, is going to experience precision issues. That is, only integers up to 15 digits are guaranteed to be exact.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Is JavaScript's Math broken?
Why JS show 25.1+61.7+13.2 = 100.00000000000001 ? Its fixed if you just change the position of the number like 13.2+25.1+61.7 = 100. Can anyone explain this.
Because you are using floating point arithmetic.
Here is an explanation of what is happening.
JavaScript uses IEEE 754 floating point math, which is a base-2 floating point format. There are many many values that cannot be represented exactly in that format, and specifically among them are decimal fractions like x.7.
It's not a compiler issue. It's an issue with the fundamental way that JavaScript represents real numbers. Many other languages would have the exact same problem.
Computers don't handle real numbers in a rigorous way, generally.