
(FPCore (x) :precision binary64 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x): return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x) return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0)); end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x): return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x) return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0)); end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}
\end{array}
(FPCore (x) :precision binary64 (* (fma 2.0 (pow x -2.0) (fma 2.0 (pow x -4.0) 2.0)) (pow x -3.0)))
double code(double x) {
return fma(2.0, pow(x, -2.0), fma(2.0, pow(x, -4.0), 2.0)) * pow(x, -3.0);
}
function code(x) return Float64(fma(2.0, (x ^ -2.0), fma(2.0, (x ^ -4.0), 2.0)) * (x ^ -3.0)) end
code[x_] := N[(N[(2.0 * N[Power[x, -2.0], $MachinePrecision] + N[(2.0 * N[Power[x, -4.0], $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(2, {x}^{-2}, \mathsf{fma}\left(2, {x}^{-4}, 2\right)\right) \cdot {x}^{-3}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 98.8%
associate-+r+98.8%
+-commutative98.8%
associate-+l+98.8%
associate-*r/98.8%
metadata-eval98.8%
Simplified98.8%
div-inv98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
+-commutative98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
pow-flip99.7%
metadata-eval99.7%
Applied egg-rr99.7%
(FPCore (x) :precision binary64 (* (pow x -3.0) (+ 2.0 (/ 2.0 (* x x)))))
double code(double x) {
return pow(x, -3.0) * (2.0 + (2.0 / (x * x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x ** (-3.0d0)) * (2.0d0 + (2.0d0 / (x * x)))
end function
public static double code(double x) {
return Math.pow(x, -3.0) * (2.0 + (2.0 / (x * x)));
}
def code(x): return math.pow(x, -3.0) * (2.0 + (2.0 / (x * x)))
function code(x) return Float64((x ^ -3.0) * Float64(2.0 + Float64(2.0 / Float64(x * x)))) end
function tmp = code(x) tmp = (x ^ -3.0) * (2.0 + (2.0 / (x * x))); end
code[x_] := N[(N[Power[x, -3.0], $MachinePrecision] * N[(2.0 + N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
{x}^{-3} \cdot \left(2 + \frac{2}{x \cdot x}\right)
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 98.8%
associate-+r+98.8%
+-commutative98.8%
associate-+l+98.8%
associate-*r/98.8%
metadata-eval98.8%
Simplified98.8%
div-inv98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
+-commutative98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
pow-flip99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Taylor expanded in x around inf 99.5%
associate-*r/99.5%
metadata-eval99.5%
Simplified99.5%
unpow299.5%
Applied egg-rr99.5%
Final simplification99.5%
(FPCore (x) :precision binary64 (* 2.0 (pow x -3.0)))
double code(double x) {
return 2.0 * pow(x, -3.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 * (x ** (-3.0d0))
end function
public static double code(double x) {
return 2.0 * Math.pow(x, -3.0);
}
def code(x): return 2.0 * math.pow(x, -3.0)
function code(x) return Float64(2.0 * (x ^ -3.0)) end
function tmp = code(x) tmp = 2.0 * (x ^ -3.0); end
code[x_] := N[(2.0 * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot {x}^{-3}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 98.8%
associate-+r+98.8%
+-commutative98.8%
associate-+l+98.8%
associate-*r/98.8%
metadata-eval98.8%
Simplified98.8%
div-inv98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
+-commutative98.8%
div-inv98.8%
fma-define98.8%
pow-flip98.8%
metadata-eval98.8%
pow-flip99.7%
metadata-eval99.7%
Applied egg-rr99.7%
Taylor expanded in x around inf 99.5%
associate-*r/99.5%
metadata-eval99.5%
Simplified99.5%
Taylor expanded in x around inf 99.0%
(FPCore (x) :precision binary64 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (+ x -1.0))))
double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x + (-1.0d0)))
end function
public static double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x + -1.0));
}
def code(x): return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x + -1.0))
function code(x) return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x + -1.0))) end
function tmp = code(x) tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x + -1.0)); end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x + -1}
\end{array}
Initial program 70.4%
Final simplification70.4%
(FPCore (x) :precision binary64 (+ (/ 1.0 (+ x -1.0)) (/ (+ -1.0 (/ 1.0 x)) x)))
double code(double x) {
return (1.0 / (x + -1.0)) + ((-1.0 + (1.0 / x)) / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + (-1.0d0))) + (((-1.0d0) + (1.0d0 / x)) / x)
end function
public static double code(double x) {
return (1.0 / (x + -1.0)) + ((-1.0 + (1.0 / x)) / x);
}
def code(x): return (1.0 / (x + -1.0)) + ((-1.0 + (1.0 / x)) / x)
function code(x) return Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(Float64(-1.0 + Float64(1.0 / x)) / x)) end
function tmp = code(x) tmp = (1.0 / (x + -1.0)) + ((-1.0 + (1.0 / x)) / x); end
code[x_] := N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 + N[(1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + -1} + \frac{-1 + \frac{1}{x}}{x}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
frac-2neg70.4%
frac-2neg70.4%
metadata-eval70.4%
frac-sub18.5%
metadata-eval18.5%
sub-neg18.5%
distribute-neg-in18.5%
metadata-eval18.5%
neg-mul-118.5%
*-commutative18.5%
sub-neg18.5%
*-commutative18.5%
neg-mul-118.5%
sub-neg18.5%
distribute-neg-in18.5%
metadata-eval18.5%
neg-mul-118.5%
*-commutative18.5%
sub-neg18.5%
*-commutative18.5%
Applied egg-rr18.5%
sub-neg18.5%
remove-double-neg18.5%
distribute-lft-in18.5%
metadata-eval18.5%
*-commutative18.5%
neg-mul-118.5%
remove-double-neg18.5%
sub-neg18.5%
remove-double-neg18.5%
distribute-lft-in18.6%
*-rgt-identity18.6%
neg-mul-118.6%
distribute-rgt-in18.5%
sub-neg18.5%
Simplified18.5%
Taylor expanded in x around inf 17.2%
Taylor expanded in x around inf 69.0%
Final simplification69.0%
(FPCore (x) :precision binary64 (+ (/ 1.0 (+ x -1.0)) (/ -1.0 x)))
double code(double x) {
return (1.0 / (x + -1.0)) + (-1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + (-1.0d0))) + ((-1.0d0) / x)
end function
public static double code(double x) {
return (1.0 / (x + -1.0)) + (-1.0 / x);
}
def code(x): return (1.0 / (x + -1.0)) + (-1.0 / x)
function code(x) return Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(-1.0 / x)) end
function tmp = code(x) tmp = (1.0 / (x + -1.0)) + (-1.0 / x); end
code[x_] := N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + -1} + \frac{-1}{x}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 69.0%
(FPCore (x) :precision binary64 (+ (/ 1.0 x) (/ -1.0 x)))
double code(double x) {
return (1.0 / x) + (-1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / x) + ((-1.0d0) / x)
end function
public static double code(double x) {
return (1.0 / x) + (-1.0 / x);
}
def code(x): return (1.0 / x) + (-1.0 / x)
function code(x) return Float64(Float64(1.0 / x) + Float64(-1.0 / x)) end
function tmp = code(x) tmp = (1.0 / x) + (-1.0 / x); end
code[x_] := N[(N[(1.0 / x), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x} + \frac{-1}{x}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 69.0%
Taylor expanded in x around inf 68.8%
(FPCore (x) :precision binary64 (/ -1.0 x))
double code(double x) {
return -1.0 / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-1.0d0) / x
end function
public static double code(double x) {
return -1.0 / x;
}
def code(x): return -1.0 / x
function code(x) return Float64(-1.0 / x) end
function tmp = code(x) tmp = -1.0 / x; end
code[x_] := N[(-1.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{x}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around inf 69.0%
Taylor expanded in x around 0 5.1%
(FPCore (x) :precision binary64 (/ -2.0 x))
double code(double x) {
return -2.0 / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / x
end function
public static double code(double x) {
return -2.0 / x;
}
def code(x): return -2.0 / x
function code(x) return Float64(-2.0 / x) end
function tmp = code(x) tmp = -2.0 / x; end
code[x_] := N[(-2.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x}
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
Taylor expanded in x around 0 5.1%
(FPCore (x) :precision binary64 -2.0)
double code(double x) {
return -2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = -2.0d0
end function
public static double code(double x) {
return -2.0;
}
def code(x): return -2.0
function code(x) return -2.0 end
function tmp = code(x) tmp = -2.0; end
code[x_] := -2.0
\begin{array}{l}
\\
-2
\end{array}
Initial program 70.4%
+-commutative70.4%
associate-+r-70.3%
sub-neg70.3%
remove-double-neg70.3%
neg-sub070.3%
associate-+l-70.3%
neg-sub070.3%
distribute-neg-frac270.3%
distribute-frac-neg270.3%
associate-+r+70.4%
+-commutative70.4%
remove-double-neg70.4%
distribute-neg-frac270.4%
sub0-neg70.4%
associate-+l-70.4%
neg-sub070.4%
Simplified70.4%
frac-2neg70.4%
frac-2neg70.4%
metadata-eval70.4%
frac-sub18.5%
metadata-eval18.5%
sub-neg18.5%
distribute-neg-in18.5%
metadata-eval18.5%
neg-mul-118.5%
*-commutative18.5%
sub-neg18.5%
*-commutative18.5%
neg-mul-118.5%
sub-neg18.5%
distribute-neg-in18.5%
metadata-eval18.5%
neg-mul-118.5%
*-commutative18.5%
sub-neg18.5%
*-commutative18.5%
Applied egg-rr18.5%
sub-neg18.5%
remove-double-neg18.5%
distribute-lft-in18.5%
metadata-eval18.5%
*-commutative18.5%
neg-mul-118.5%
remove-double-neg18.5%
sub-neg18.5%
remove-double-neg18.5%
distribute-lft-in18.6%
*-rgt-identity18.6%
neg-mul-118.6%
distribute-rgt-in18.5%
sub-neg18.5%
Simplified18.5%
Taylor expanded in x around inf 17.2%
Taylor expanded in x around 0 3.3%
(FPCore (x) :precision binary64 (/ 2.0 (* x (- (* x x) 1.0))))
double code(double x) {
return 2.0 / (x * ((x * x) - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (x * ((x * x) - 1.0d0))
end function
public static double code(double x) {
return 2.0 / (x * ((x * x) - 1.0));
}
def code(x): return 2.0 / (x * ((x * x) - 1.0))
function code(x) return Float64(2.0 / Float64(x * Float64(Float64(x * x) - 1.0))) end
function tmp = code(x) tmp = 2.0 / (x * ((x * x) - 1.0)); end
code[x_] := N[(2.0 / N[(x * N[(N[(x * x), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{x \cdot \left(x \cdot x - 1\right)}
\end{array}
herbie shell --seed 2024114
(FPCore (x)
:name "3frac (problem 3.3.3)"
:precision binary64
:pre (> (fabs x) 1.0)
:alt
(/ 2.0 (* x (- (* x x) 1.0)))
(+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))