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" <helly@php.net> wrote in message
news:719431098.20050209002446@marcus-boerger.de...
> 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
