
(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 6 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
(*
x_s
(if (<= (- (exp x_m) (exp (- x_m))) 0.001)
(/
(*
x_m
(+
2.0
(*
(* x_m x_m)
(+ 0.3333333333333333 (* (* x_m x_m) 0.016666666666666666)))))
2.0)
(/ (expm1 x_m) 2.0))))x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
double tmp;
if ((exp(x_m) - exp(-x_m)) <= 0.001) {
tmp = (x_m * (2.0 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 2.0;
} else {
tmp = expm1(x_m) / 2.0;
}
return x_s * tmp;
}
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 ((Math.exp(x_m) - Math.exp(-x_m)) <= 0.001) {
tmp = (x_m * (2.0 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 2.0;
} else {
tmp = Math.expm1(x_m) / 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 (math.exp(x_m) - math.exp(-x_m)) <= 0.001: tmp = (x_m * (2.0 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 2.0 else: tmp = math.expm1(x_m) / 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 (Float64(exp(x_m) - exp(Float64(-x_m))) <= 0.001) tmp = Float64(Float64(x_m * Float64(2.0 + Float64(Float64(x_m * x_m) * Float64(0.3333333333333333 + Float64(Float64(x_m * x_m) * 0.016666666666666666))))) / 2.0); else tmp = Float64(expm1(x_m) / 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_] := N[(x$95$s * If[LessEqual[N[(N[Exp[x$95$m], $MachinePrecision] - N[Exp[(-x$95$m)], $MachinePrecision]), $MachinePrecision], 0.001], N[(N[(x$95$m * N[(2.0 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(0.3333333333333333 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.016666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(Exp[x$95$m] - 1), $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}\;e^{x\_m} - e^{-x\_m} \leq 0.001:\\
\;\;\;\;\frac{x\_m \cdot \left(2 + \left(x\_m \cdot x\_m\right) \cdot \left(0.3333333333333333 + \left(x\_m \cdot x\_m\right) \cdot 0.016666666666666666\right)\right)}{2}\\
\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{expm1}\left(x\_m\right)}{2}\\
\end{array}
\end{array}
if (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 1e-3Initial program 41.8%
Taylor expanded in x around 0 94.9%
*-commutative94.9%
Simplified94.9%
unpow294.9%
Applied egg-rr94.9%
unpow294.9%
Applied egg-rr94.9%
if 1e-3 < (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) Initial program 100.0%
Taylor expanded in x around 0 100.0%
mul-1-neg100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
sub-neg100.0%
metadata-eval100.0%
Applied egg-rr100.0%
metadata-eval100.0%
sub-neg100.0%
expm1-define100.0%
Simplified100.0%
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
(*
(* x_m x_m)
(+ 0.3333333333333333 (* (* x_m x_m) 0.016666666666666666)))))
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 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 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 + ((x_m * x_m) * (0.3333333333333333d0 + ((x_m * x_m) * 0.016666666666666666d0))))) / 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 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 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 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 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 * Float64(2.0 + Float64(Float64(x_m * x_m) * Float64(0.3333333333333333 + Float64(Float64(x_m * x_m) * 0.016666666666666666))))) / 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 + ((x_m * x_m) * (0.3333333333333333 + ((x_m * x_m) * 0.016666666666666666))))) / 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[(2.0 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(0.3333333333333333 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.016666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $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 \left(2 + \left(x\_m \cdot x\_m\right) \cdot \left(0.3333333333333333 + \left(x\_m \cdot x\_m\right) \cdot 0.016666666666666666\right)\right)}{2}
\end{array}
Initial program 57.9%
Taylor expanded in x around 0 91.5%
*-commutative91.5%
Simplified91.5%
unpow291.5%
Applied egg-rr91.5%
unpow291.5%
Applied egg-rr91.5%
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
(+
1.0
(*
x_m
(+ 0.25 (* x_m (+ 0.08333333333333333 (* x_m 0.020833333333333332)))))))))x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * (x_m * (1.0 + (x_m * (0.25 + (x_m * (0.08333333333333333 + (x_m * 0.020833333333333332)))))));
}
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 * (1.0d0 + (x_m * (0.25d0 + (x_m * (0.08333333333333333d0 + (x_m * 0.020833333333333332d0)))))))
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 * (1.0 + (x_m * (0.25 + (x_m * (0.08333333333333333 + (x_m * 0.020833333333333332)))))));
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * (x_m * (1.0 + (x_m * (0.25 + (x_m * (0.08333333333333333 + (x_m * 0.020833333333333332)))))))
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * Float64(x_m * Float64(1.0 + Float64(x_m * Float64(0.25 + Float64(x_m * Float64(0.08333333333333333 + Float64(x_m * 0.020833333333333332)))))))) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * (x_m * (1.0 + (x_m * (0.25 + (x_m * (0.08333333333333333 + (x_m * 0.020833333333333332))))))); 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[(x$95$m * N[(1.0 + N[(x$95$m * N[(0.25 + N[(x$95$m * N[(0.08333333333333333 + N[(x$95$m * 0.020833333333333332), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \left(x\_m \cdot \left(1 + x\_m \cdot \left(0.25 + x\_m \cdot \left(0.08333333333333333 + x\_m \cdot 0.020833333333333332\right)\right)\right)\right)
\end{array}
Initial program 57.9%
Taylor expanded in x around 0 31.9%
mul-1-neg31.9%
unsub-neg31.9%
Simplified31.9%
Taylor expanded in x around 0 66.2%
*-commutative66.2%
Simplified66.2%
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 (+ 1.0 (* (* x_m x_m) 0.16666666666666666)))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * (x_m * (1.0 + ((x_m * x_m) * 0.16666666666666666)));
}
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 * (1.0d0 + ((x_m * x_m) * 0.16666666666666666d0)))
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 * (1.0 + ((x_m * x_m) * 0.16666666666666666)));
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * (x_m * (1.0 + ((x_m * x_m) * 0.16666666666666666)))
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * Float64(x_m * Float64(1.0 + Float64(Float64(x_m * x_m) * 0.16666666666666666)))) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * (x_m * (1.0 + ((x_m * x_m) * 0.16666666666666666))); 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[(x$95$m * N[(1.0 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \left(x\_m \cdot \left(1 + \left(x\_m \cdot x\_m\right) \cdot 0.16666666666666666\right)\right)
\end{array}
Initial program 57.9%
Taylor expanded in x around 0 91.5%
*-commutative91.5%
Simplified91.5%
Taylor expanded in x around 0 85.6%
unpow291.5%
Applied egg-rr85.6%
Final simplification85.6%
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 (+ 1.0 (* x_m 0.25)))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * (x_m * (1.0 + (x_m * 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 * (x_m * (1.0d0 + (x_m * 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 * (x_m * (1.0 + (x_m * 0.25)));
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * (x_m * (1.0 + (x_m * 0.25)))
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * Float64(x_m * Float64(1.0 + Float64(x_m * 0.25)))) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * (x_m * (1.0 + (x_m * 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 * N[(x$95$m * N[(1.0 + N[(x$95$m * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot \left(x\_m \cdot \left(1 + x\_m \cdot 0.25\right)\right)
\end{array}
Initial program 57.9%
Taylor expanded in x around 0 31.9%
mul-1-neg31.9%
unsub-neg31.9%
Simplified31.9%
Taylor expanded in x around 0 60.6%
*-commutative60.6%
Simplified60.6%
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))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
return x_s * x_m;
}
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
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;
}
x\_m = math.fabs(x) x\_s = math.copysign(1.0, x) def code(x_s, x_m): return x_s * x_m
x\_m = abs(x) x\_s = copysign(1.0, x) function code(x_s, x_m) return Float64(x_s * x_m) end
x\_m = abs(x); x\_s = sign(x) * abs(1.0); function tmp = code(x_s, x_m) tmp = x_s * x_m; 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 * x$95$m), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)
\\
x\_s \cdot x\_m
\end{array}
Initial program 57.9%
Taylor expanded in x around 0 91.5%
*-commutative91.5%
Simplified91.5%
Taylor expanded in x around 0 47.8%
herbie shell --seed 2024169
(FPCore (x)
:name "Hyperbolic sine"
:precision binary64
(/ (- (exp x) (exp (- x))) 2.0))