Re: weird math

[straz@cambridge.apple.com (Steve Strassmann)]

 >Date: Wed, 25 Aug 93 19:18:12 EST
 >From: kab (Kim Barrett)
 >To: sr0o+@andrew.cmu.edu (Steven Ritter)
 >Subject: Re: weird math
 >Cc: info-mcl@ministry.cambridge.apple.com
 >
 >> According to my reading of CLtL2 (292-293), this should not happen:
 >> ? (= 1.4 (/ 7 5))
 >> NIL
 >
 >Check the top of p.290, which discusses issue 
 >CONTAGION-ON-NUMERICAL-COMPARISONS:TRANSITIVE.  I guess Guy was a little bit 
 >lazy in finding the places affected by that change.  There really ought to be 
 >some mention of it in section 12.3.
 >

Yeah, unfortunately this is what floating point is all about:

? (coerce 1.4s0 'double-float)
1.399999976158142
? single-float-epsilon
1.1107651257113995E-16
? (> (- 1.4d0 1.4s0) single-float-epsilon)
t