
(FPCore (x) :precision binary64 (/ (- (exp x) (exp (- x))) 2.0))
double code(double x) {
return (exp(x) - exp(-x)) / 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (exp(x) - exp(-x)) / 2.0d0
end function
public static double code(double x) {
return (Math.exp(x) - Math.exp(-x)) / 2.0;
}
def code(x): return (math.exp(x) - math.exp(-x)) / 2.0
function code(x) return Float64(Float64(exp(x) - exp(Float64(-x))) / 2.0) end
function tmp = code(x) tmp = (exp(x) - exp(-x)) / 2.0; end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - N[Exp[(-x)], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{e^{x} - e^{-x}}{2}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (/ (- (exp x) (exp (- x))) 2.0))
double code(double x) {
return (exp(x) - exp(-x)) / 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (exp(x) - exp(-x)) / 2.0d0
end function
public static double code(double x) {
return (Math.exp(x) - Math.exp(-x)) / 2.0;
}
def code(x): return (math.exp(x) - math.exp(-x)) / 2.0
function code(x) return Float64(Float64(exp(x) - exp(Float64(-x))) / 2.0) end
function tmp = code(x) tmp = (exp(x) - exp(-x)) / 2.0; end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - N[Exp[(-x)], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{e^{x} - e^{-x}}{2}
\end{array}
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
:precision binary64
(let* ((t_0 (- (exp x_m) (exp (- x_m)))))
(*
x_s
(if (<= t_0 5e-6)
(/ (* x_m (fma (* x_m 0.3333333333333333) x_m 2.0)) 2.0)
(/ t_0 2.0)))))x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
double t_0 = exp(x_m) - exp(-x_m);
double tmp;
if (t_0 <= 5e-6) {
tmp = (x_m * fma((x_m * 0.3333333333333333), x_m, 2.0)) / 2.0;
} else {
tmp = t_0 / 2.0;
}
return x_s * tmp;
}
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) t_0 = Float64(exp(x_m) - exp(Float64(-x_m))) tmp = 0.0 if (t_0 <= 5e-6) tmp = Float64(Float64(x_m * fma(Float64(x_m * 0.3333333333333333), x_m, 2.0)) / 2.0); else tmp = Float64(t_0 / 2.0); end return Float64(x_s * tmp) end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[(N[Exp[x$95$m], $MachinePrecision] - N[Exp[(-x$95$m)], $MachinePrecision]), $MachinePrecision]}, N[(x$95$s * If[LessEqual[t$95$0, 5e-6], N[(N[(x$95$m * N[(N[(x$95$m * 0.3333333333333333), $MachinePrecision] * x$95$m + 2.0), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], N[(t$95$0 / 2.0), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
\begin{array}{l}
t_0 := e^{x\_m} - e^{-x\_m}\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;t\_0 \leq 5 \cdot 10^{-6}:\\
\;\;\;\;\frac{x\_m \cdot \mathsf{fma}\left(x\_m \cdot 0.3333333333333333, x\_m, 2\right)}{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{t\_0}{2}\\
\end{array}
\end{array}
\end{array}
if (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 5.00000000000000041e-6Initial program 37.1%
Taylor expanded in x around 0 88.7%
+-commutative88.7%
unpow288.7%
associate-*r*88.7%
fma-define88.7%
Applied egg-rr88.7%
if 5.00000000000000041e-6 < (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) Initial program 100.0%
Final simplification91.5%
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
:precision binary64
(*
x_s
(if (<= x_m 2.45)
(/ (* x_m 2.0) 2.0)
(/ (* 0.3333333333333333 (pow x_m 3.0)) 2.0))))x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
double tmp;
if (x_m <= 2.45) {
tmp = (x_m * 2.0) / 2.0;
} else {
tmp = (0.3333333333333333 * pow(x_m, 3.0)) / 2.0;
}
return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
real(8), intent (in) :: x_s
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 2.45d0) then
tmp = (x_m * 2.0d0) / 2.0d0
else
tmp = (0.3333333333333333d0 * (x_m ** 3.0d0)) / 2.0d0
end if
code = x_s * tmp
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
double tmp;
if (x_m <= 2.45) {
tmp = (x_m * 2.0) / 2.0;
} else {
tmp = (0.3333333333333333 * Math.pow(x_m, 3.0)) / 2.0;
}
return x_s * tmp;
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): tmp = 0 if x_m <= 2.45: tmp = (x_m * 2.0) / 2.0 else: tmp = (0.3333333333333333 * math.pow(x_m, 3.0)) / 2.0 return x_s * tmp
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) tmp = 0.0 if (x_m <= 2.45) tmp = Float64(Float64(x_m * 2.0) / 2.0); else tmp = Float64(Float64(0.3333333333333333 * (x_m ^ 3.0)) / 2.0); end return Float64(x_s * tmp) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp_2 = code(x_s, x_m) tmp = 0.0; if (x_m <= 2.45) tmp = (x_m * 2.0) / 2.0; else tmp = (0.3333333333333333 * (x_m ^ 3.0)) / 2.0; end tmp_2 = x_s * tmp; end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[x$95$m, 2.45], N[(N[(x$95$m * 2.0), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(0.3333333333333333 * N[Power[x$95$m, 3.0], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;x\_m \leq 2.45:\\
\;\;\;\;\frac{x\_m \cdot 2}{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{0.3333333333333333 \cdot {x\_m}^{3}}{2}\\
\end{array}
\end{array}
if x < 2.4500000000000002Initial program 37.1%
Taylor expanded in x around 0 68.9%
if 2.4500000000000002 < x Initial program 100.0%
Taylor expanded in x around 0 54.3%
Taylor expanded in x around inf 54.3%
Final simplification65.3%
x\_m = (fabs.f64 x) x\_s = (copysign.f64 #s(literal 1 binary64) x) (FPCore (x_s x_m) :precision binary64 (* x_s (/ (* x_m (fma (* x_m 0.3333333333333333) x_m 2.0)) 2.0)))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * ((x_m * fma((x_m * 0.3333333333333333), x_m, 2.0)) / 2.0);
}
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * Float64(Float64(x_m * fma(Float64(x_m * 0.3333333333333333), x_m, 2.0)) / 2.0)) end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(N[(x$95$m * N[(N[(x$95$m * 0.3333333333333333), $MachinePrecision] * x$95$m + 2.0), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \frac{x\_m \cdot \mathsf{fma}\left(x\_m \cdot 0.3333333333333333, x\_m, 2\right)}{2}
\end{array}
Initial program 52.8%
Taylor expanded in x around 0 80.1%
+-commutative80.1%
unpow280.1%
associate-*r*80.1%
fma-define80.1%
Applied egg-rr80.1%
Final simplification80.1%
x\_m = (fabs.f64 x) x\_s = (copysign.f64 #s(literal 1 binary64) x) (FPCore (x_s x_m) :precision binary64 (* x_s (/ (* x_m 2.0) 2.0)))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * ((x_m * 2.0) / 2.0);
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
real(8), intent (in) :: x_s
real(8), intent (in) :: x_m
code = x_s * ((x_m * 2.0d0) / 2.0d0)
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
return x_s * ((x_m * 2.0) / 2.0);
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * ((x_m * 2.0) / 2.0)
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * Float64(Float64(x_m * 2.0) / 2.0)) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * ((x_m * 2.0) / 2.0); end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(N[(x$95$m * 2.0), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \frac{x\_m \cdot 2}{2}
\end{array}
Initial program 52.8%
Taylor expanded in x around 0 53.0%
Final simplification53.0%
x\_m = (fabs.f64 x) x\_s = (copysign.f64 #s(literal 1 binary64) x) (FPCore (x_s x_m) :precision binary64 (* x_s 4.0))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * 4.0;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
real(8), intent (in) :: x_s
real(8), intent (in) :: x_m
code = x_s * 4.0d0
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
return x_s * 4.0;
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * 4.0
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * 4.0) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * 4.0; end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * 4.0), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot 4
\end{array}
Initial program 52.8%
Applied egg-rr2.8%
Final simplification2.8%
x\_m = (fabs.f64 x) x\_s = (copysign.f64 #s(literal 1 binary64) x) (FPCore (x_s x_m) :precision binary64 (* x_s 0.25))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * 0.25;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
real(8), intent (in) :: x_s
real(8), intent (in) :: x_m
code = x_s * 0.25d0
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
return x_s * 0.25;
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * 0.25
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * 0.25) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * 0.25; end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * 0.25), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot 0.25
\end{array}
Initial program 52.8%
Applied egg-rr2.8%
Final simplification2.8%
x\_m = (fabs.f64 x) x\_s = (copysign.f64 #s(literal 1 binary64) x) (FPCore (x_s x_m) :precision binary64 (* x_s 0.0))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * 0.0;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
real(8), intent (in) :: x_s
real(8), intent (in) :: x_m
code = x_s * 0.0d0
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
return x_s * 0.0;
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * 0.0
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * 0.0) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * 0.0; end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * 0.0), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot 0
\end{array}
Initial program 52.8%
Applied egg-rr3.5%
Final simplification3.5%
herbie shell --seed 2024092
(FPCore (x)
:name "Hyperbolic sine"
:precision binary64
(/ (- (exp x) (exp (- x))) 2.0))