19 Oct
2006
19 Oct
'06
9:06 a.m.
tirath wrote:
The query... Before I started using the library, I had this assumption: let A be a float with an exact representation (i.e. width=0). If we cast A to a double, the resulting double will have a non-zero width - specifically the width will be equal to the extra precision afforded to doubles vs floats.
I'm not familiar with the interval lib, but if a float is an exact value, then promoting it to a wider type will result in an exact value as well. I assume what you're looking for is a way to say "here is a float, that is holding the nearest representable value, but is inexact (has up to 0.5ulp error)" ? Then that error would propagate to the double as you expect. John.