That's my whole point Marcus, but the nature of the native floating point types is something you can get around by implementing your own floating point type, based on a base-10 system, in the same way that for example bcmath does it. So my suggestion is; stop using float and double, and make your own type. Small performance hit, and it will probably cost you about 1 byte extra per floating point variable, but then it will be accurate.
Ron "Marcus Boerger" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Hello Ron, > > it doesn't matter how accurate your floating or whatever you call it is. > Financial applications require native support which can be realized using > bcmath. Whatever you think besides that - the problem is that any errors > accumulate - that's the nature of float. > > If you would like to know whats IEEE 754 read this > http://docs.sun.com/source/806-3568/ncg_goldberg.html > > best regards > marcus > > Tuesday, February 8, 2005, 8:15:31 PM, you wrote: > > > Personal recent frustrating float issues made me think of the following... > > > At the moment apparently the C-type double is used for PHP's float (or > > double if you please) storage. I believe it is the philosophy of PHP to make > > things easy for its users, and in this perspective I was thinking.. hasn't > > the time come to reimplement the PHP float type in a decimal-safe way? Of > > course it would be a small performance hit, but not too noticable I think, > > especially when utilizing simd instructions which a compiler may or may not > > already do. I think, especially with todays powerful systems, performance > > (although still a big concern) is no longer the only primary concern. > > Shouldn't PHP abandon the speed of the double in C on this one, and > > implement a custom implementation of the floating point type which is much > > more accurate, even at the cost of a few extra bytes and cycles? > > Userfriendlyness over performance. I think it would be one hell of a feature > > for PHP to be mathematically correct, a world in which 1.5555 is really > > 1.5555 and not something that approaches it, and where (for example) > > rounding it would result in expected behaviour. I think PHP would > > automagically be more suitable for various (financial for example) > > applications which could potentially result in more popularity for PHP as a > > whole. > > > I know there are alternatives for accurate mathematics, but they (naturally) > > depend on strings which make them a lot slower than a native solution would > > be, and besides that, they are less nice to use compared to +,-,/,*,% > > operators. > > > It's just an idea of course, and I'm curious if there are others who feel > > the same way about this. > > > Ron > > > > > -- > Best regards, > Marcus mailto:[EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
