diff options
Diffstat (limited to 'src/algebra/sf.spad.pamphlet')
| -rw-r--r-- | src/algebra/sf.spad.pamphlet | 33 |
1 files changed, 16 insertions, 17 deletions
diff --git a/src/algebra/sf.spad.pamphlet b/src/algebra/sf.spad.pamphlet index e15fdddd..fc01b769 100644 --- a/src/algebra/sf.spad.pamphlet +++ b/src/algebra/sf.spad.pamphlet @@ -286,7 +286,6 @@ DoubleFloat(): Join(FloatingPointSystem, DifferentialRing, import %fmaxval: () -> % from Foreign Builtin import %fbase: () -> PositiveInteger from Foreign Builtin import %fprec: () -> PositiveInteger from Foreign Builtin - import %fmanexp: % -> Record(man: %,exp: Integer) from Foreign Builtin import %i2f: Integer -> % from Foreign Builtin import %fabs: % -> % from Foreign Builtin import %fneg: % -> % from Foreign Builtin @@ -327,12 +326,16 @@ DoubleFloat(): Join(FloatingPointSystem, DifferentialRing, import %fatanh: % -> % from Foreign Builtin import %fcstpi: () -> % from Foreign Builtin import %fNaN?: % -> Boolean from Foreign Builtin - - manexp: % -> MER + import %fdecode: % -> List Integer from Foreign Builtin + import %lfirst: List Integer -> Integer from Foreign Builtin + import %lsecond: List Integer -> Integer from Foreign Builtin + import %lthird: List Integer -> Integer from Foreign Builtin base() == %fbase() - mantissa x == manexp(x).MANTISSA - exponent x == manexp(x).EXPONENT + mantissa x == + fp := %fdecode x + %lfirst fp * %lthird fp + exponent x == %lsecond %fdecode x precision() == %fprec() bits() == base() = 2 => precision() @@ -394,7 +397,7 @@ DoubleFloat(): Join(FloatingPointSystem, DifferentialRing, acoth x == atanh(1/x) asech x == acosh(1/x) x:% / y:% == %fdiv(x,y) - negative? x == x < 0 + negative? x == sign x < 0 zero? x == x = 0 one? x == x = 1 hash x == %hash x @@ -438,18 +441,14 @@ DoubleFloat(): Join(FloatingPointSystem, DifferentialRing, x = (%i2f(n := wholePart x)) => n "failed" - sign(x) == retract FLOAT_-SIGN(x,1)$Lisp + sign(x) == %lthird %fdecode x abs x == %fabs x - positive? x == 0 < x - manexp(x) == - zero? x => [0,0] - s := sign x - x := abs x - if x > max()$% then - return [s*mantissa(max())+1,exponent max()] - me: Record(man: %,exp: Integer) := %fmanexp x - two53 := base()**precision() - [s*wholePart(two53 * me.man ),me.exp-precision()] + positive? x == sign x > 0 + manexp(x: %): MER == + fp := %fdecode x + m := %lfirst fp + zero? m => [m,0] + [%lfirst fp * %lthird fp, %lsecond fp] -- rationalApproximation(y,d,b) == -- this is the quotient remainder algorithm (requires wholePart operation) |