>>>>> "Richard" == Richard Fateman <fateman at EECS.Berkeley.EDU> writes:
Richard> This application of interval analysis for numeric
Richard> sub-type determination at compile time seems to me to be
Richard> rather different from computation with intervals, as is
Richard> done by Mathematica ( using Interval[{a,b }].) There may
Richard> be more of a relationship than I see right here, but I
Richard> think the primary use of this CMU stuff is to determine
Richard> when possible that (sqrt x) will return a [real]
Richard> double-float and not a complex number.
Yes, CMUCL uses this for type-derivation and is mostly so the compiler
knows that sqrt or log will return a real number instead of real or
complex.
I'm not familiar with Mathematica's interval computation, but if
Interval[{a,b}], where a and b are numbers, then I would think it's
similar, except that CMUCL doesn't do directed rounding.
Ray