Is there a definitive solution to javascript floating-point errors?

Question

I write line of business applications. I\'d like to build a front-end end using Javascript and am trying to figure out how to deal with, for a business user, are floating p

Answer 1

One answer is to do the math in decimal instead of binary. Then you never have to worry about the decimal <=> binary conversion errors. You'd represent the numbers as binary digits in an array or a string and write the math routines yourself.

Here are some bignumber libraries you can look into if you don't want to go to that trouble:

http://jsfromhell.com/classes/bignumber

http://stz-ida.de/html/oss/js_bigdecimal.html.en

Answer 2

According to Douglas Crockford, the only way around this problem is scale your values to integer. Make sure it really is an integer by using Math.round on the scaled value. (DC does not talk about the rounding part, but I discovered it was necessary. e.g. Math.round(1.1 *100)) Do calculation(s). When you are done with the math scale back to original precision. See JavaScript: The Good Parts "Floating Point" section.

Answer 3

the only definite solution seems to be writing your own arbitrary precision number type working on strings internally -- which will be complicated and horribly slow.