Standard Apple Numerics Environment, the
floating point environment shared by
680x0 Apple
Macintoshes.
Superseded by PowerPC Numerics, which are more portable, but don't have a nearly as nifty sounding acronym. Because the operations supported by SANE are a subset of PPCN's, PowerPC Machintoshes are able to run 680x0 applications in the SANE floating point environment, and will do so until the applications in question are recompiled for the PowerPC architecture.
SANE has fewer types than PPCN, most notably lacking the double double type. It does, however, support the comp and extended types (80 and 96 bits, respectively). SANE actually performs all floating point operations with extended precision, whereas PPCN's operations are not type restricted in this manner.
Oddly, because of this, SANE features better overflow and underflow protection than PPCN. An example given on http://developer.apple.com is for the expression (max_double + max_double) / max_double, where all three variables are of type double.
SANE will cast everything into extended type, which prevents an overflow on the initial add instruction. The expression correctly evaluates to 2, after the extended-precision division. PPCN, however, will perform both operations at double-precision, resulting in an overflow after the addition, and an incorrect result of positive infinity.