
(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}
(FPCore (x)
:precision binary64
(let* ((t_0 (- (exp x) (exp (- x)))))
(if (or (<= t_0 (- INFINITY)) (not (<= t_0 2e-8)))
(/ t_0 2.0)
(/ (+ (* (* x x) (* x 0.3333333333333333)) (* x 2.0)) 2.0))))
double code(double x) {
double t_0 = exp(x) - exp(-x);
double tmp;
if ((t_0 <= -((double) INFINITY)) || !(t_0 <= 2e-8)) {
tmp = t_0 / 2.0;
} else {
tmp = (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0;
}
return tmp;
}
public static double code(double x) {
double t_0 = Math.exp(x) - Math.exp(-x);
double tmp;
if ((t_0 <= -Double.POSITIVE_INFINITY) || !(t_0 <= 2e-8)) {
tmp = t_0 / 2.0;
} else {
tmp = (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0;
}
return tmp;
}
def code(x): t_0 = math.exp(x) - math.exp(-x) tmp = 0 if (t_0 <= -math.inf) or not (t_0 <= 2e-8): tmp = t_0 / 2.0 else: tmp = (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0 return tmp
function code(x) t_0 = Float64(exp(x) - exp(Float64(-x))) tmp = 0.0 if ((t_0 <= Float64(-Inf)) || !(t_0 <= 2e-8)) tmp = Float64(t_0 / 2.0); else tmp = Float64(Float64(Float64(Float64(x * x) * Float64(x * 0.3333333333333333)) + Float64(x * 2.0)) / 2.0); end return tmp end
function tmp_2 = code(x) t_0 = exp(x) - exp(-x); tmp = 0.0; if ((t_0 <= -Inf) || ~((t_0 <= 2e-8))) tmp = t_0 / 2.0; else tmp = (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0; end tmp_2 = tmp; end
code[x_] := Block[{t$95$0 = N[(N[Exp[x], $MachinePrecision] - N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$0, (-Infinity)], N[Not[LessEqual[t$95$0, 2e-8]], $MachinePrecision]], N[(t$95$0 / 2.0), $MachinePrecision], N[(N[(N[(N[(x * x), $MachinePrecision] * N[(x * 0.3333333333333333), $MachinePrecision]), $MachinePrecision] + N[(x * 2.0), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := e^{x} - e^{-x}\\
\mathbf{if}\;t_0 \leq -\infty \lor \neg \left(t_0 \leq 2 \cdot 10^{-8}\right):\\
\;\;\;\;\frac{t_0}{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{\left(x \cdot x\right) \cdot \left(x \cdot 0.3333333333333333\right) + x \cdot 2}{2}\\
\end{array}
\end{array}
if (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < -inf.0 or 2e-8 < (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) Initial program 100.0%
if -inf.0 < (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 2e-8Initial program 9.0%
Taylor expanded in x around 0 100.0%
expm1-log1p-u100.0%
expm1-udef99.5%
log1p-udef99.5%
add-exp-log99.5%
Applied egg-rr99.5%
add-exp-log99.5%
log1p-udef99.5%
expm1-udef100.0%
expm1-log1p-u100.0%
*-commutative100.0%
unpow3100.0%
associate-*l*100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (x) :precision binary64 (if (or (<= x -2.5) (not (<= x 2.5))) (/ (* x (* (* x x) 0.3333333333333333)) 2.0) (/ (* x 2.0) 2.0)))
double code(double x) {
double tmp;
if ((x <= -2.5) || !(x <= 2.5)) {
tmp = (x * ((x * x) * 0.3333333333333333)) / 2.0;
} else {
tmp = (x * 2.0) / 2.0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-2.5d0)) .or. (.not. (x <= 2.5d0))) then
tmp = (x * ((x * x) * 0.3333333333333333d0)) / 2.0d0
else
tmp = (x * 2.0d0) / 2.0d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -2.5) || !(x <= 2.5)) {
tmp = (x * ((x * x) * 0.3333333333333333)) / 2.0;
} else {
tmp = (x * 2.0) / 2.0;
}
return tmp;
}
def code(x): tmp = 0 if (x <= -2.5) or not (x <= 2.5): tmp = (x * ((x * x) * 0.3333333333333333)) / 2.0 else: tmp = (x * 2.0) / 2.0 return tmp
function code(x) tmp = 0.0 if ((x <= -2.5) || !(x <= 2.5)) tmp = Float64(Float64(x * Float64(Float64(x * x) * 0.3333333333333333)) / 2.0); else tmp = Float64(Float64(x * 2.0) / 2.0); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -2.5) || ~((x <= 2.5))) tmp = (x * ((x * x) * 0.3333333333333333)) / 2.0; else tmp = (x * 2.0) / 2.0; end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -2.5], N[Not[LessEqual[x, 2.5]], $MachinePrecision]], N[(N[(x * N[(N[(x * x), $MachinePrecision] * 0.3333333333333333), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(x * 2.0), $MachinePrecision] / 2.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.5 \lor \neg \left(x \leq 2.5\right):\\
\;\;\;\;\frac{x \cdot \left(\left(x \cdot x\right) \cdot 0.3333333333333333\right)}{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{x \cdot 2}{2}\\
\end{array}
\end{array}
if x < -2.5 or 2.5 < x Initial program 100.0%
Taylor expanded in x around 0 72.6%
unpow372.6%
associate-*r*72.6%
distribute-rgt-out72.6%
*-commutative72.6%
associate-*l*72.6%
fma-def72.6%
Simplified72.6%
Taylor expanded in x around inf 72.6%
unpow272.6%
Simplified72.6%
if -2.5 < x < 2.5Initial program 9.8%
Taylor expanded in x around 0 98.9%
Final simplification84.7%
(FPCore (x) :precision binary64 (/ (+ (* (* x x) (* x 0.3333333333333333)) (* x 2.0)) 2.0))
double code(double x) {
return (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (((x * x) * (x * 0.3333333333333333d0)) + (x * 2.0d0)) / 2.0d0
end function
public static double code(double x) {
return (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0;
}
def code(x): return (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0
function code(x) return Float64(Float64(Float64(Float64(x * x) * Float64(x * 0.3333333333333333)) + Float64(x * 2.0)) / 2.0) end
function tmp = code(x) tmp = (((x * x) * (x * 0.3333333333333333)) + (x * 2.0)) / 2.0; end
code[x_] := N[(N[(N[(N[(x * x), $MachinePrecision] * N[(x * 0.3333333333333333), $MachinePrecision]), $MachinePrecision] + N[(x * 2.0), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(x \cdot x\right) \cdot \left(x \cdot 0.3333333333333333\right) + x \cdot 2}{2}
\end{array}
Initial program 58.4%
Taylor expanded in x around 0 85.0%
expm1-log1p-u65.4%
expm1-udef65.1%
log1p-udef65.1%
add-exp-log84.8%
Applied egg-rr84.8%
add-exp-log65.1%
log1p-udef65.1%
expm1-udef65.4%
expm1-log1p-u85.0%
*-commutative85.0%
unpow385.0%
associate-*l*85.0%
Applied egg-rr85.0%
Final simplification85.0%
(FPCore (x) :precision binary64 (/ (* x (+ 2.0 (* (* x x) 0.3333333333333333))) 2.0))
double code(double x) {
return (x * (2.0 + ((x * x) * 0.3333333333333333))) / 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x * (2.0d0 + ((x * x) * 0.3333333333333333d0))) / 2.0d0
end function
public static double code(double x) {
return (x * (2.0 + ((x * x) * 0.3333333333333333))) / 2.0;
}
def code(x): return (x * (2.0 + ((x * x) * 0.3333333333333333))) / 2.0
function code(x) return Float64(Float64(x * Float64(2.0 + Float64(Float64(x * x) * 0.3333333333333333))) / 2.0) end
function tmp = code(x) tmp = (x * (2.0 + ((x * x) * 0.3333333333333333))) / 2.0; end
code[x_] := N[(N[(x * N[(2.0 + N[(N[(x * x), $MachinePrecision] * 0.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{x \cdot \left(2 + \left(x \cdot x\right) \cdot 0.3333333333333333\right)}{2}
\end{array}
Initial program 58.4%
Taylor expanded in x around 0 85.0%
unpow385.0%
associate-*r*85.0%
distribute-rgt-out85.0%
*-commutative85.0%
associate-*l*85.0%
fma-def85.0%
Simplified85.0%
fma-udef85.0%
associate-*r*85.0%
Applied egg-rr85.0%
Final simplification85.0%
(FPCore (x) :precision binary64 (/ (* x 2.0) 2.0))
double code(double x) {
return (x * 2.0) / 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x * 2.0d0) / 2.0d0
end function
public static double code(double x) {
return (x * 2.0) / 2.0;
}
def code(x): return (x * 2.0) / 2.0
function code(x) return Float64(Float64(x * 2.0) / 2.0) end
function tmp = code(x) tmp = (x * 2.0) / 2.0; end
code[x_] := N[(N[(x * 2.0), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{x \cdot 2}{2}
\end{array}
Initial program 58.4%
Taylor expanded in x around 0 48.6%
Final simplification48.6%
(FPCore (x) :precision binary64 -1.0)
double code(double x) {
return -1.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = -1.0d0
end function
public static double code(double x) {
return -1.0;
}
def code(x): return -1.0
function code(x) return -1.0 end
function tmp = code(x) tmp = -1.0; end
code[x_] := -1.0
\begin{array}{l}
\\
-1
\end{array}
Initial program 58.4%
Applied egg-rr2.8%
Final simplification2.8%
(FPCore (x) :precision binary64 0.0)
double code(double x) {
return 0.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.0d0
end function
public static double code(double x) {
return 0.0;
}
def code(x): return 0.0
function code(x) return 0.0 end
function tmp = code(x) tmp = 0.0; end
code[x_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 58.4%
Applied egg-rr3.1%
Final simplification3.1%
herbie shell --seed 2023283
(FPCore (x)
:name "Hyperbolic sine"
:precision binary64
(/ (- (exp x) (exp (- x))) 2.0))