
(FPCore (x) :precision binary64 (/ 2.0 (+ (exp x) (exp (- x)))))
double code(double x) {
return 2.0 / (exp(x) + exp(-x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (exp(x) + exp(-x))
end function
public static double code(double x) {
return 2.0 / (Math.exp(x) + Math.exp(-x));
}
def code(x): return 2.0 / (math.exp(x) + math.exp(-x))
function code(x) return Float64(2.0 / Float64(exp(x) + exp(Float64(-x)))) end
function tmp = code(x) tmp = 2.0 / (exp(x) + exp(-x)); end
code[x_] := N[(2.0 / N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{e^{x} + e^{-x}}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (/ 2.0 (+ (exp x) (exp (- x)))))
double code(double x) {
return 2.0 / (exp(x) + exp(-x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (exp(x) + exp(-x))
end function
public static double code(double x) {
return 2.0 / (Math.exp(x) + Math.exp(-x));
}
def code(x): return 2.0 / (math.exp(x) + math.exp(-x))
function code(x) return Float64(2.0 / Float64(exp(x) + exp(Float64(-x)))) end
function tmp = code(x) tmp = 2.0 / (exp(x) + exp(-x)); end
code[x_] := N[(2.0 / N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{e^{x} + e^{-x}}
\end{array}
(FPCore (x) :precision binary64 (/ 2.0 (+ (exp x) (exp (- x)))))
double code(double x) {
return 2.0 / (exp(x) + exp(-x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (exp(x) + exp(-x))
end function
public static double code(double x) {
return 2.0 / (Math.exp(x) + Math.exp(-x));
}
def code(x): return 2.0 / (math.exp(x) + math.exp(-x))
function code(x) return Float64(2.0 / Float64(exp(x) + exp(Float64(-x)))) end
function tmp = code(x) tmp = 2.0 / (exp(x) + exp(-x)); end
code[x_] := N[(2.0 / N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{e^{x} + e^{-x}}
\end{array}
Initial program 100.0%
(FPCore (x) :precision binary64 (/ 2.0 (+ (exp x) (- 1.0 x))))
double code(double x) {
return 2.0 / (exp(x) + (1.0 - x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (exp(x) + (1.0d0 - x))
end function
public static double code(double x) {
return 2.0 / (Math.exp(x) + (1.0 - x));
}
def code(x): return 2.0 / (math.exp(x) + (1.0 - x))
function code(x) return Float64(2.0 / Float64(exp(x) + Float64(1.0 - x))) end
function tmp = code(x) tmp = 2.0 / (exp(x) + (1.0 - x)); end
code[x_] := N[(2.0 / N[(N[Exp[x], $MachinePrecision] + N[(1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{e^{x} + \left(1 - x\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 76.2%
mul-1-neg76.2%
unsub-neg76.2%
Simplified76.2%
(FPCore (x) :precision binary64 (/ 2.0 (+ (+ 1.0 (* x (+ 1.0 (* x (+ 0.5 (* x 0.16666666666666666)))))) (+ 1.0 (* x (+ (* x 0.5) -1.0))))))
double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))) + (1.0 + (x * ((x * 0.5) + -1.0))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 + (x * (1.0d0 + (x * (0.5d0 + (x * 0.16666666666666666d0)))))) + (1.0d0 + (x * ((x * 0.5d0) + (-1.0d0)))))
end function
public static double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))) + (1.0 + (x * ((x * 0.5) + -1.0))));
}
def code(x): return 2.0 / ((1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))) + (1.0 + (x * ((x * 0.5) + -1.0))))
function code(x) return Float64(2.0 / Float64(Float64(1.0 + Float64(x * Float64(1.0 + Float64(x * Float64(0.5 + Float64(x * 0.16666666666666666)))))) + Float64(1.0 + Float64(x * Float64(Float64(x * 0.5) + -1.0))))) end
function tmp = code(x) tmp = 2.0 / ((1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))) + (1.0 + (x * ((x * 0.5) + -1.0)))); end
code[x_] := N[(2.0 / N[(N[(1.0 + N[(x * N[(1.0 + N[(x * N[(0.5 + N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 + N[(x * N[(N[(x * 0.5), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 + x \cdot \left(1 + x \cdot \left(0.5 + x \cdot 0.16666666666666666\right)\right)\right) + \left(1 + x \cdot \left(x \cdot 0.5 + -1\right)\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 74.8%
Taylor expanded in x around 0 52.0%
*-lft-identity52.0%
*-lft-identity52.0%
*-commutative52.0%
Simplified52.0%
Taylor expanded in x around 0 73.2%
*-commutative73.2%
Simplified73.2%
Final simplification73.2%
(FPCore (x) :precision binary64 (/ 2.0 (+ (- 1.0 x) (+ 1.0 (* x (+ 1.0 (* x (+ 0.5 (* x 0.16666666666666666)))))))))
double code(double x) {
return 2.0 / ((1.0 - x) + (1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 - x) + (1.0d0 + (x * (1.0d0 + (x * (0.5d0 + (x * 0.16666666666666666d0)))))))
end function
public static double code(double x) {
return 2.0 / ((1.0 - x) + (1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))));
}
def code(x): return 2.0 / ((1.0 - x) + (1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666)))))))
function code(x) return Float64(2.0 / Float64(Float64(1.0 - x) + Float64(1.0 + Float64(x * Float64(1.0 + Float64(x * Float64(0.5 + Float64(x * 0.16666666666666666)))))))) end
function tmp = code(x) tmp = 2.0 / ((1.0 - x) + (1.0 + (x * (1.0 + (x * (0.5 + (x * 0.16666666666666666))))))); end
code[x_] := N[(2.0 / N[(N[(1.0 - x), $MachinePrecision] + N[(1.0 + N[(x * N[(1.0 + N[(x * N[(0.5 + N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 - x\right) + \left(1 + x \cdot \left(1 + x \cdot \left(0.5 + x \cdot 0.16666666666666666\right)\right)\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 76.2%
mul-1-neg76.2%
unsub-neg76.2%
Simplified76.2%
Taylor expanded in x around 0 85.8%
*-lft-identity52.0%
*-lft-identity52.0%
*-commutative52.0%
Simplified85.8%
Final simplification85.8%
(FPCore (x) :precision binary64 (/ 2.0 (+ (+ 1.0 (* x (+ 1.0 (* x 0.5)))) (* x (+ (/ 1.0 x) -1.0)))))
double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + (x * ((1.0 / x) + -1.0)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 + (x * (1.0d0 + (x * 0.5d0)))) + (x * ((1.0d0 / x) + (-1.0d0))))
end function
public static double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + (x * ((1.0 / x) + -1.0)));
}
def code(x): return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + (x * ((1.0 / x) + -1.0)))
function code(x) return Float64(2.0 / Float64(Float64(1.0 + Float64(x * Float64(1.0 + Float64(x * 0.5)))) + Float64(x * Float64(Float64(1.0 / x) + -1.0)))) end
function tmp = code(x) tmp = 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + (x * ((1.0 / x) + -1.0))); end
code[x_] := N[(2.0 / N[(N[(1.0 + N[(x * N[(1.0 + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(x * N[(N[(1.0 / x), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 + x \cdot \left(1 + x \cdot 0.5\right)\right) + x \cdot \left(\frac{1}{x} + -1\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 76.2%
mul-1-neg76.2%
unsub-neg76.2%
Simplified76.2%
Taylor expanded in x around 0 77.4%
*-commutative77.4%
Simplified77.4%
Taylor expanded in x around inf 77.4%
Final simplification77.4%
(FPCore (x) :precision binary64 (/ 2.0 (+ (+ 1.0 (* x (+ 1.0 (* x 0.5)))) (+ (- 2.0 x) -1.0))))
double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + ((2.0 - x) + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 + (x * (1.0d0 + (x * 0.5d0)))) + ((2.0d0 - x) + (-1.0d0)))
end function
public static double code(double x) {
return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + ((2.0 - x) + -1.0));
}
def code(x): return 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + ((2.0 - x) + -1.0))
function code(x) return Float64(2.0 / Float64(Float64(1.0 + Float64(x * Float64(1.0 + Float64(x * 0.5)))) + Float64(Float64(2.0 - x) + -1.0))) end
function tmp = code(x) tmp = 2.0 / ((1.0 + (x * (1.0 + (x * 0.5)))) + ((2.0 - x) + -1.0)); end
code[x_] := N[(2.0 / N[(N[(1.0 + N[(x * N[(1.0 + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(2.0 - x), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 + x \cdot \left(1 + x \cdot 0.5\right)\right) + \left(\left(2 - x\right) + -1\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 76.2%
mul-1-neg76.2%
unsub-neg76.2%
Simplified76.2%
Taylor expanded in x around 0 77.4%
*-commutative77.4%
Simplified77.4%
expm1-log1p-u64.9%
Applied egg-rr64.9%
expm1-undefine64.9%
sub-neg64.9%
log1p-undefine64.9%
rem-exp-log77.4%
associate-+r-77.4%
metadata-eval77.4%
metadata-eval77.4%
Simplified77.4%
(FPCore (x) :precision binary64 (/ 2.0 (+ (+ 1.0 (* x (+ (* x 0.5) -1.0))) (+ x 1.0))))
double code(double x) {
return 2.0 / ((1.0 + (x * ((x * 0.5) + -1.0))) + (x + 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 + (x * ((x * 0.5d0) + (-1.0d0)))) + (x + 1.0d0))
end function
public static double code(double x) {
return 2.0 / ((1.0 + (x * ((x * 0.5) + -1.0))) + (x + 1.0));
}
def code(x): return 2.0 / ((1.0 + (x * ((x * 0.5) + -1.0))) + (x + 1.0))
function code(x) return Float64(2.0 / Float64(Float64(1.0 + Float64(x * Float64(Float64(x * 0.5) + -1.0))) + Float64(x + 1.0))) end
function tmp = code(x) tmp = 2.0 / ((1.0 + (x * ((x * 0.5) + -1.0))) + (x + 1.0)); end
code[x_] := N[(2.0 / N[(N[(1.0 + N[(x * N[(N[(x * 0.5), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 + x \cdot \left(x \cdot 0.5 + -1\right)\right) + \left(x + 1\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 74.8%
Taylor expanded in x around 0 52.0%
*-lft-identity52.0%
*-lft-identity52.0%
*-commutative52.0%
Simplified52.0%
Taylor expanded in x around 0 73.2%
*-commutative73.2%
Simplified73.2%
Taylor expanded in x around 0 77.4%
Final simplification77.4%
(FPCore (x) :precision binary64 (/ 2.0 (+ (- 1.0 x) (+ 1.0 (* x (* x 0.5))))))
double code(double x) {
return 2.0 / ((1.0 - x) + (1.0 + (x * (x * 0.5))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / ((1.0d0 - x) + (1.0d0 + (x * (x * 0.5d0))))
end function
public static double code(double x) {
return 2.0 / ((1.0 - x) + (1.0 + (x * (x * 0.5))));
}
def code(x): return 2.0 / ((1.0 - x) + (1.0 + (x * (x * 0.5))))
function code(x) return Float64(2.0 / Float64(Float64(1.0 - x) + Float64(1.0 + Float64(x * Float64(x * 0.5))))) end
function tmp = code(x) tmp = 2.0 / ((1.0 - x) + (1.0 + (x * (x * 0.5)))); end
code[x_] := N[(2.0 / N[(N[(1.0 - x), $MachinePrecision] + N[(1.0 + N[(x * N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(1 - x\right) + \left(1 + x \cdot \left(x \cdot 0.5\right)\right)}
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 76.2%
mul-1-neg76.2%
unsub-neg76.2%
Simplified76.2%
Taylor expanded in x around 0 77.4%
*-commutative77.4%
Simplified77.4%
Taylor expanded in x around inf 77.4%
Taylor expanded in x around inf 76.5%
*-commutative76.5%
Simplified76.5%
Final simplification76.5%
(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 100.0%
Taylor expanded in x around 0 52.9%
herbie shell --seed 2024119
(FPCore (x)
:name "Hyperbolic secant"
:precision binary64
(/ 2.0 (+ (exp x) (exp (- x)))))