[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

*To*: macrakis@osf.org*Subject*: Re: bounded, infinite ranges?*From*: andyw@ibeam.ht.intel.com (Andy Wilson)*Date*: Wed, 21 Oct 92 17:33 PDT*Cc*: info-dylan@cambridge.apple.com

Stavros Macrakis writes: ----------------------------------------------------------- The elements of the range should be in general calculated as from+I*by rather than as ((from+by)+by)+by+... This also guarantees that you don't get killed by round-off. On the other hand, it does mean that more than one element of the range may have the same value. ----------------------------------------------------------- Due to the miracle of floating point arithmetic, there is always a value for "by:" where even from+I*by == from for at least some part of the range. This leads to one of two undesirable states: 1) more than one element of the range has the same value, as Stavros suggests, or 2) the (size) of the range is not equal to the number of values one would see iterating over it. Again, these unpleasant facts of floating point life could be avoided if from/up-to/by were constrained to be <rational>. atw

- Prev by Date:
**Re: contractual programming** - Next by Date:
**Re: Dylan Constants** - Previous by thread:
**Re: bounded, infinite ranges?** - Next by thread:
**Re: bounded, infinite ranges?** - Index(es):