
(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 8 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 (sinh x))
double code(double x) {
return sinh(x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = sinh(x)
end function
public static double code(double x) {
return Math.sinh(x);
}
def code(x): return math.sinh(x)
function code(x) return sinh(x) end
function tmp = code(x) tmp = sinh(x); end
code[x_] := N[Sinh[x], $MachinePrecision]
\begin{array}{l}
\\
\sinh x
\end{array}
Initial program 55.0%
lift--.f64N/A
lift-exp.f64N/A
lift-exp.f64N/A
lift-neg.f64N/A
sinh-undefN/A
*-commutativeN/A
lower-*.f64N/A
lower-sinh.f64100.0
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
associate-/l*N/A
metadata-evalN/A
*-rgt-identity100.0
Applied rewrites100.0%
(FPCore (x)
:precision binary64
(if (<= (- (exp x) (exp (- x))) 0.4)
(* (* (fma 0.3333333333333333 (* x x) 2.0) x) 0.5)
(*
(* (* (* (fma 0.016666666666666666 (* x x) 0.3333333333333333) x) x) x)
0.5)))
double code(double x) {
double tmp;
if ((exp(x) - exp(-x)) <= 0.4) {
tmp = (fma(0.3333333333333333, (x * x), 2.0) * x) * 0.5;
} else {
tmp = (((fma(0.016666666666666666, (x * x), 0.3333333333333333) * x) * x) * x) * 0.5;
}
return tmp;
}
function code(x) tmp = 0.0 if (Float64(exp(x) - exp(Float64(-x))) <= 0.4) tmp = Float64(Float64(fma(0.3333333333333333, Float64(x * x), 2.0) * x) * 0.5); else tmp = Float64(Float64(Float64(Float64(fma(0.016666666666666666, Float64(x * x), 0.3333333333333333) * x) * x) * x) * 0.5); end return tmp end
code[x_] := If[LessEqual[N[(N[Exp[x], $MachinePrecision] - N[Exp[(-x)], $MachinePrecision]), $MachinePrecision], 0.4], N[(N[(N[(0.3333333333333333 * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision], N[(N[(N[(N[(N[(0.016666666666666666 * N[(x * x), $MachinePrecision] + 0.3333333333333333), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;e^{x} - e^{-x} \leq 0.4:\\
\;\;\;\;\left(\mathsf{fma}\left(0.3333333333333333, x \cdot x, 2\right) \cdot x\right) \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.016666666666666666, x \cdot x, 0.3333333333333333\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot 0.5\\
\end{array}
\end{array}
if (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 0.40000000000000002Initial program 42.2%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6485.5
Applied rewrites85.5%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-evalN/A
Applied rewrites85.5%
if 0.40000000000000002 < (-.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) Initial program 100.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6485.2
Applied rewrites85.2%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-eval85.2
Applied rewrites85.2%
Taylor expanded in x around inf
Applied rewrites85.2%
(FPCore (x)
:precision binary64
(*
0.5
(*
(fma
(*
(fma
(fma 0.0003968253968253968 (* x x) 0.016666666666666666)
(* x x)
0.3333333333333333)
x)
x
2.0)
x)))
double code(double x) {
return 0.5 * (fma((fma(fma(0.0003968253968253968, (x * x), 0.016666666666666666), (x * x), 0.3333333333333333) * x), x, 2.0) * x);
}
function code(x) return Float64(0.5 * Float64(fma(Float64(fma(fma(0.0003968253968253968, Float64(x * x), 0.016666666666666666), Float64(x * x), 0.3333333333333333) * x), x, 2.0) * x)) end
code[x_] := N[(0.5 * N[(N[(N[(N[(N[(0.0003968253968253968 * N[(x * x), $MachinePrecision] + 0.016666666666666666), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.3333333333333333), $MachinePrecision] * x), $MachinePrecision] * x + 2.0), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003968253968253968, x \cdot x, 0.016666666666666666\right), x \cdot x, 0.3333333333333333\right) \cdot x, x, 2\right) \cdot x\right)
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6491.9
Applied rewrites91.9%
Applied rewrites91.9%
lift-/.f64N/A
div-invN/A
metadata-evalN/A
lower-*.f6491.9
Applied rewrites91.9%
Final simplification91.9%
(FPCore (x)
:precision binary64
(*
(*
(fma
(* (* (fma 0.0003968253968253968 (* x x) 0.016666666666666666) x) x)
(* x x)
2.0)
x)
0.5))
double code(double x) {
return (fma(((fma(0.0003968253968253968, (x * x), 0.016666666666666666) * x) * x), (x * x), 2.0) * x) * 0.5;
}
function code(x) return Float64(Float64(fma(Float64(Float64(fma(0.0003968253968253968, Float64(x * x), 0.016666666666666666) * x) * x), Float64(x * x), 2.0) * x) * 0.5) end
code[x_] := N[(N[(N[(N[(N[(N[(0.0003968253968253968 * N[(x * x), $MachinePrecision] + 0.016666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(\left(\mathsf{fma}\left(0.0003968253968253968, x \cdot x, 0.016666666666666666\right) \cdot x\right) \cdot x, x \cdot x, 2\right) \cdot x\right) \cdot 0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6491.9
Applied rewrites91.9%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-eval91.9
Applied rewrites91.9%
Taylor expanded in x around inf
Applied rewrites91.7%
(FPCore (x) :precision binary64 (* (* (fma (* (fma (* 0.016666666666666666 x) x 0.3333333333333333) x) x 2.0) x) 0.5))
double code(double x) {
return (fma((fma((0.016666666666666666 * x), x, 0.3333333333333333) * x), x, 2.0) * x) * 0.5;
}
function code(x) return Float64(Float64(fma(Float64(fma(Float64(0.016666666666666666 * x), x, 0.3333333333333333) * x), x, 2.0) * x) * 0.5) end
code[x_] := N[(N[(N[(N[(N[(N[(0.016666666666666666 * x), $MachinePrecision] * x + 0.3333333333333333), $MachinePrecision] * x), $MachinePrecision] * x + 2.0), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(\mathsf{fma}\left(0.016666666666666666 \cdot x, x, 0.3333333333333333\right) \cdot x, x, 2\right) \cdot x\right) \cdot 0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6489.5
Applied rewrites89.5%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-eval89.5
Applied rewrites89.5%
Applied rewrites89.5%
Applied rewrites89.5%
(FPCore (x) :precision binary64 (* (* (fma (* 0.016666666666666666 (* x x)) (* x x) 2.0) x) 0.5))
double code(double x) {
return (fma((0.016666666666666666 * (x * x)), (x * x), 2.0) * x) * 0.5;
}
function code(x) return Float64(Float64(fma(Float64(0.016666666666666666 * Float64(x * x)), Float64(x * x), 2.0) * x) * 0.5) end
code[x_] := N[(N[(N[(N[(0.016666666666666666 * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(0.016666666666666666 \cdot \left(x \cdot x\right), x \cdot x, 2\right) \cdot x\right) \cdot 0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6489.5
Applied rewrites89.5%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-eval89.5
Applied rewrites89.5%
Taylor expanded in x around inf
Applied rewrites89.4%
(FPCore (x) :precision binary64 (* (* (fma 0.3333333333333333 (* x x) 2.0) x) 0.5))
double code(double x) {
return (fma(0.3333333333333333, (x * x), 2.0) * x) * 0.5;
}
function code(x) return Float64(Float64(fma(0.3333333333333333, Float64(x * x), 2.0) * x) * 0.5) end
code[x_] := N[(N[(N[(0.3333333333333333 * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] * x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(0.3333333333333333, x \cdot x, 2\right) \cdot x\right) \cdot 0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6482.9
Applied rewrites82.9%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-evalN/A
Applied rewrites82.9%
(FPCore (x) :precision binary64 (* (* 2.0 x) 0.5))
double code(double x) {
return (2.0 * x) * 0.5;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (2.0d0 * x) * 0.5d0
end function
public static double code(double x) {
return (2.0 * x) * 0.5;
}
def code(x): return (2.0 * x) * 0.5
function code(x) return Float64(Float64(2.0 * x) * 0.5) end
function tmp = code(x) tmp = (2.0 * x) * 0.5; end
code[x_] := N[(N[(2.0 * x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(2 \cdot x\right) \cdot 0.5
\end{array}
Initial program 55.0%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f6450.6
Applied rewrites50.6%
lift-/.f64N/A
div-invN/A
lower-*.f64N/A
metadata-evalN/A
Applied rewrites50.6%
herbie shell --seed 2024248
(FPCore (x)
:name "Hyperbolic sine"
:precision binary64
(/ (- (exp x) (exp (- x))) 2.0))