floating point errors

i have this function:

round(number*1000000000)/1000000000

i use it on all of my sprite font numbers, in order to avoid floating points error.

This work for 99% of the cases, and fixes most error caused by multiplying numbers

Yet, a number like this: 4418829.9

will be converted to: 4418829.900000001

i need to support up to 6 digits after dot

i dont understand how float number works and i need help

*simply removing a single 0 from 1000000000, seems to fix it for this specifc number

*i thought also trying to cut the last digit because i dont need that many

*but, if i try those fixes i will not know for sure the problem is fixed

this might have happend because the bumber was too long

im going to split the number to 2 parts

right and left side of decimal point

im going to use the rounding only on the right part and the sum 2 parts