Doc #47901 [Com]: Need to define "large numbers" in base_convert limitations

Edit report at https://bugs.php.net/bug.php?id=47901&edit=1 ID: 47901 Comment by: exploringbinary at gmail dot com Reported by: exploringbinary at gmail dot com Summary: Need to define "large numbers" in base_convert limitations Status: Not a bug Type: Documentation Problem Package: Documentation problem Operating System: Windows PHP Version: Irrelevant Block user comment: N Private report: N New Comment: In my article http://www.exploringbinary.com/the-safe-range-for-phps-base-convert/ I define the limits for safe base_convert() conversions. You can consider drawing from it to update your documentation. Previous Comments: ------------------------------------------------------------------------ [2009-11-19 13:14:33] exploringbinary at gmail dot com Yes, I know there's a link. My bug report quotes text from the paragraph that contains it. There is nothing within that link, that I can see, that addresses my concern. If you see something there, please be specific. ------------------------------------------------------------------------ [2009-11-19 11:14:41] vrana@php.net There's a link to Floating point numbers. ------------------------------------------------------------------------ [2009-04-05 14:24:17] exploringbinary at gmail dot com Description: ------------ The documentation for base_convert says "base_convert() may lose precision on large numbers...". Can you define exactly what "large number" is? Without knowing the limit, it's hard to trust the results. I know you can't specify a single limit, because it could vary by implementation. It still would be useful to define a limit for the most common implementations, like 32 bit unsigned integers or IEEE double floating-point. In the case of IEEE double floating-point, my guess is that the limit is 2^53, meaning that all integers less than or equal to 2^53 will be converted correctly. (All integers from 0 to 2^53 can fit in an IEEE double.) Related bug reports: Bug #23564 base_convert() ignores last character Bug #35874 base_convert is off on numbers greater than 13 decimal places ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=47901&edit=1