
(FPCore (x) :precision binary64 (+ (- (exp x) 2.0) (exp (- x))))
double code(double x) {
return (exp(x) - 2.0) + exp(-x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (exp(x) - 2.0d0) + exp(-x)
end function
public static double code(double x) {
return (Math.exp(x) - 2.0) + Math.exp(-x);
}
def code(x): return (math.exp(x) - 2.0) + math.exp(-x)
function code(x) return Float64(Float64(exp(x) - 2.0) + exp(Float64(-x))) end
function tmp = code(x) tmp = (exp(x) - 2.0) + exp(-x); end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(e^{x} - 2\right) + e^{-x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (+ (- (exp x) 2.0) (exp (- x))))
double code(double x) {
return (exp(x) - 2.0) + exp(-x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (exp(x) - 2.0d0) + exp(-x)
end function
public static double code(double x) {
return (Math.exp(x) - 2.0) + Math.exp(-x);
}
def code(x): return (math.exp(x) - 2.0) + math.exp(-x)
function code(x) return Float64(Float64(exp(x) - 2.0) + exp(Float64(-x))) end
function tmp = code(x) tmp = (exp(x) - 2.0) + exp(-x); end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(e^{x} - 2\right) + e^{-x}
\end{array}
(FPCore (x)
:precision binary64
(*
x
(*
x
(+
1.0
(*
x
(*
x
(+
0.08333333333333333
(*
(* x x)
(+ 0.002777777777777778 (* x (* x 4.96031746031746e-5)))))))))))
double code(double x) {
return x * (x * (1.0 + (x * (x * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + (x * (x * 4.96031746031746e-5)))))))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x * (1.0d0 + (x * (x * (0.08333333333333333d0 + ((x * x) * (0.002777777777777778d0 + (x * (x * 4.96031746031746d-5)))))))))
end function
public static double code(double x) {
return x * (x * (1.0 + (x * (x * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + (x * (x * 4.96031746031746e-5)))))))));
}
def code(x): return x * (x * (1.0 + (x * (x * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + (x * (x * 4.96031746031746e-5)))))))))
function code(x) return Float64(x * Float64(x * Float64(1.0 + Float64(x * Float64(x * Float64(0.08333333333333333 + Float64(Float64(x * x) * Float64(0.002777777777777778 + Float64(x * Float64(x * 4.96031746031746e-5)))))))))) end
function tmp = code(x) tmp = x * (x * (1.0 + (x * (x * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + (x * (x * 4.96031746031746e-5))))))))); end
code[x_] := N[(x * N[(x * N[(1.0 + N[(x * N[(x * N[(0.08333333333333333 + N[(N[(x * x), $MachinePrecision] * N[(0.002777777777777778 + N[(x * N[(x * 4.96031746031746e-5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + x \cdot \left(x \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)\right)\right)\right)
\end{array}
Initial program 54.3%
associate-+l-N/A
sub-negN/A
+-lowering-+.f64N/A
exp-lowering-exp.f64N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
remove-double-negN/A
+-lowering-+.f64N/A
exp-negN/A
/-lowering-/.f64N/A
exp-lowering-exp.f64N/A
metadata-eval54.4%
Simplified54.4%
Taylor expanded in x around 0
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.8%
Simplified99.8%
associate-*l*N/A
*-commutativeN/A
*-lowering-*.f64N/A
Applied egg-rr99.8%
Final simplification99.8%
(FPCore (x)
:precision binary64
(*
(* x x)
(+
1.0
(*
(* x x)
(+
0.08333333333333333
(* (* x x) (+ 0.002777777777777778 (* (* x x) 4.96031746031746e-5))))))))
double code(double x) {
return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x * x) * (1.0d0 + ((x * x) * (0.08333333333333333d0 + ((x * x) * (0.002777777777777778d0 + ((x * x) * 4.96031746031746d-5))))))
end function
public static double code(double x) {
return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))));
}
def code(x): return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))))
function code(x) return Float64(Float64(x * x) * Float64(1.0 + Float64(Float64(x * x) * Float64(0.08333333333333333 + Float64(Float64(x * x) * Float64(0.002777777777777778 + Float64(Float64(x * x) * 4.96031746031746e-5))))))) end
function tmp = code(x) tmp = (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5)))))); end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(1.0 + N[(N[(x * x), $MachinePrecision] * N[(0.08333333333333333 + N[(N[(x * x), $MachinePrecision] * N[(0.002777777777777778 + N[(N[(x * x), $MachinePrecision] * 4.96031746031746e-5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)
\end{array}
Initial program 54.3%
associate-+l-N/A
sub-negN/A
+-lowering-+.f64N/A
exp-lowering-exp.f64N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
remove-double-negN/A
+-lowering-+.f64N/A
exp-negN/A
/-lowering-/.f64N/A
exp-lowering-exp.f64N/A
metadata-eval54.4%
Simplified54.4%
Taylor expanded in x around 0
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.8%
Simplified99.8%
(FPCore (x)
:precision binary64
(*
x
(+
x
(*
x
(* (* x x) (+ 0.08333333333333333 (* (* x x) 0.002777777777777778)))))))
double code(double x) {
return x * (x + (x * ((x * x) * (0.08333333333333333 + ((x * x) * 0.002777777777777778)))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x + (x * ((x * x) * (0.08333333333333333d0 + ((x * x) * 0.002777777777777778d0)))))
end function
public static double code(double x) {
return x * (x + (x * ((x * x) * (0.08333333333333333 + ((x * x) * 0.002777777777777778)))));
}
def code(x): return x * (x + (x * ((x * x) * (0.08333333333333333 + ((x * x) * 0.002777777777777778)))))
function code(x) return Float64(x * Float64(x + Float64(x * Float64(Float64(x * x) * Float64(0.08333333333333333 + Float64(Float64(x * x) * 0.002777777777777778)))))) end
function tmp = code(x) tmp = x * (x + (x * ((x * x) * (0.08333333333333333 + ((x * x) * 0.002777777777777778))))); end
code[x_] := N[(x * N[(x + N[(x * N[(N[(x * x), $MachinePrecision] * N[(0.08333333333333333 + N[(N[(x * x), $MachinePrecision] * 0.002777777777777778), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x + x \cdot \left(\left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot 0.002777777777777778\right)\right)\right)
\end{array}
Initial program 54.3%
associate-+l-N/A
sub-negN/A
+-lowering-+.f64N/A
exp-lowering-exp.f64N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
remove-double-negN/A
+-lowering-+.f64N/A
exp-negN/A
/-lowering-/.f64N/A
exp-lowering-exp.f64N/A
metadata-eval54.4%
Simplified54.4%
Taylor expanded in x around 0
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.6%
Simplified99.6%
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f6499.6%
Applied egg-rr99.6%
associate-*l*N/A
distribute-lft-outN/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f6499.6%
Applied egg-rr99.6%
Final simplification99.6%
(FPCore (x) :precision binary64 (* x (+ x (* x (* 0.08333333333333333 (* x x))))))
double code(double x) {
return x * (x + (x * (0.08333333333333333 * (x * x))));
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x + (x * (0.08333333333333333d0 * (x * x))))
end function
public static double code(double x) {
return x * (x + (x * (0.08333333333333333 * (x * x))));
}
def code(x): return x * (x + (x * (0.08333333333333333 * (x * x))))
function code(x) return Float64(x * Float64(x + Float64(x * Float64(0.08333333333333333 * Float64(x * x))))) end
function tmp = code(x) tmp = x * (x + (x * (0.08333333333333333 * (x * x)))); end
code[x_] := N[(x * N[(x + N[(x * N[(0.08333333333333333 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x + x \cdot \left(0.08333333333333333 \cdot \left(x \cdot x\right)\right)\right)
\end{array}
Initial program 54.3%
associate-+l-N/A
sub-negN/A
+-lowering-+.f64N/A
exp-lowering-exp.f64N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
remove-double-negN/A
+-lowering-+.f64N/A
exp-negN/A
/-lowering-/.f64N/A
exp-lowering-exp.f64N/A
metadata-eval54.4%
Simplified54.4%
Taylor expanded in x around 0
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.6%
Simplified99.6%
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f6499.6%
Applied egg-rr99.6%
associate-*l*N/A
distribute-lft-outN/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f6499.6%
Applied egg-rr99.6%
Taylor expanded in x around 0
unpow3N/A
unpow2N/A
associate-*r*N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.2%
Simplified99.2%
Final simplification99.2%
(FPCore (x) :precision binary64 (* x x))
double code(double x) {
return x * x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * x
end function
public static double code(double x) {
return x * x;
}
def code(x): return x * x
function code(x) return Float64(x * x) end
function tmp = code(x) tmp = x * x; end
code[x_] := N[(x * x), $MachinePrecision]
\begin{array}{l}
\\
x \cdot x
\end{array}
Initial program 54.3%
associate-+l-N/A
sub-negN/A
+-lowering-+.f64N/A
exp-lowering-exp.f64N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
remove-double-negN/A
+-lowering-+.f64N/A
exp-negN/A
/-lowering-/.f64N/A
exp-lowering-exp.f64N/A
metadata-eval54.4%
Simplified54.4%
Taylor expanded in x around 0
unpow2N/A
*-lowering-*.f6498.4%
Simplified98.4%
(FPCore (x) :precision binary64 (let* ((t_0 (sinh (/ x 2.0)))) (* 4.0 (* t_0 t_0))))
double code(double x) {
double t_0 = sinh((x / 2.0));
return 4.0 * (t_0 * t_0);
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = sinh((x / 2.0d0))
code = 4.0d0 * (t_0 * t_0)
end function
public static double code(double x) {
double t_0 = Math.sinh((x / 2.0));
return 4.0 * (t_0 * t_0);
}
def code(x): t_0 = math.sinh((x / 2.0)) return 4.0 * (t_0 * t_0)
function code(x) t_0 = sinh(Float64(x / 2.0)) return Float64(4.0 * Float64(t_0 * t_0)) end
function tmp = code(x) t_0 = sinh((x / 2.0)); tmp = 4.0 * (t_0 * t_0); end
code[x_] := Block[{t$95$0 = N[Sinh[N[(x / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(4.0 * N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sinh \left(\frac{x}{2}\right)\\
4 \cdot \left(t\_0 \cdot t\_0\right)
\end{array}
\end{array}
herbie shell --seed 2024140
(FPCore (x)
:name "exp2 (problem 3.3.7)"
:precision binary64
:pre (<= (fabs x) 710.0)
:alt
(! :herbie-platform default (* 4 (* (sinh (/ x 2)) (sinh (/ x 2)))))
(+ (- (exp x) 2.0) (exp (- x))))