Always false float comparisons

[Ola Fosheim Grøstad via Digitalmars-d]

On Monday, 16 May 2016 at 09:00:49 UTC, Marco Leise wrote:
> Ola's example could be some X-ray imaging format. Although
> it is still a vague example,

I don't think quantization is a particularly vague example! I 
think that is rather common.

Doing something like floor(x*(1<<24))*(1.0/(1<<24)) to quantize 
to 24 bit is just silly and inefficient.

Error diffusion is useful in scenarios where you want to reduce 
the accumulation-error or avoid banding. It can be used in audio 
in many other settings.

Anyway, irregular higher precision is almost always worse than 
regular lower precision when computing time series, comparing 
results or doing unit testing.