
(FPCore (x) :precision binary64 (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))
double code(double x) {
return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (6.0d0 * (x - 1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))
end function
public static double code(double x) {
return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * Math.sqrt(x)));
}
def code(x): return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * math.sqrt(x)))
function code(x) return Float64(Float64(6.0 * Float64(x - 1.0)) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x)))) end
function tmp = code(x) tmp = (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x))); end
code[x_] := N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))
double code(double x) {
return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (6.0d0 * (x - 1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))
end function
public static double code(double x) {
return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * Math.sqrt(x)));
}
def code(x): return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * math.sqrt(x)))
function code(x) return Float64(Float64(6.0 * Float64(x - 1.0)) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x)))) end
function tmp = code(x) tmp = (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x))); end
code[x_] := N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}
\end{array}
(FPCore (x) :precision binary64 (* (/ (- x 1.0) (fma (sqrt x) 4.0 (+ 1.0 x))) 6.0))
double code(double x) {
return ((x - 1.0) / fma(sqrt(x), 4.0, (1.0 + x))) * 6.0;
}
function code(x) return Float64(Float64(Float64(x - 1.0) / fma(sqrt(x), 4.0, Float64(1.0 + x))) * 6.0) end
code[x_] := N[(N[(N[(x - 1.0), $MachinePrecision] / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 6.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)} \cdot 6
\end{array}
Initial program 99.8%
lift-/.f64N/A
lift-*.f64N/A
associate-/l*N/A
*-commutativeN/A
lower-*.f64N/A
lower-/.f64100.0
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
lower-fma.f64100.0
lift-+.f64N/A
+-commutativeN/A
lower-+.f64100.0
Applied rewrites100.0%
(FPCore (x) :precision binary64 (if (<= x 3.5) (/ (fma 6.0 x -6.0) (fma (sqrt x) 4.0 1.0)) (/ (* x 6.0) (fma 4.0 (sqrt x) (+ 1.0 x)))))
double code(double x) {
double tmp;
if (x <= 3.5) {
tmp = fma(6.0, x, -6.0) / fma(sqrt(x), 4.0, 1.0);
} else {
tmp = (x * 6.0) / fma(4.0, sqrt(x), (1.0 + x));
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 3.5) tmp = Float64(fma(6.0, x, -6.0) / fma(sqrt(x), 4.0, 1.0)); else tmp = Float64(Float64(x * 6.0) / fma(4.0, sqrt(x), Float64(1.0 + x))); end return tmp end
code[x_] := If[LessEqual[x, 3.5], N[(N[(6.0 * x + -6.0), $MachinePrecision] / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(N[(x * 6.0), $MachinePrecision] / N[(4.0 * N[Sqrt[x], $MachinePrecision] + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 3.5:\\
\;\;\;\;\frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{x \cdot 6}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\
\end{array}
\end{array}
if x < 3.5Initial program 100.0%
Taylor expanded in x around inf
fp-cancel-sub-sign-invN/A
distribute-rgt-inN/A
metadata-evalN/A
associate-*l*N/A
lft-mult-inverseN/A
metadata-evalN/A
lower-fma.f64100.0
Applied rewrites100.0%
lift-+.f64N/A
lift-+.f64N/A
+-commutativeN/A
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f64100.0
Applied rewrites100.0%
Taylor expanded in x around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
if 3.5 < x Initial program 99.7%
Taylor expanded in x around inf
fp-cancel-sub-sign-invN/A
distribute-rgt-inN/A
metadata-evalN/A
associate-*l*N/A
lft-mult-inverseN/A
metadata-evalN/A
lower-fma.f6499.7
Applied rewrites99.7%
lift-+.f64N/A
lift-+.f64N/A
+-commutativeN/A
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f6499.7
Applied rewrites99.7%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f6497.3
Applied rewrites97.3%
(FPCore (x) :precision binary64 (if (<= x 27.0) (/ (fma 6.0 x -6.0) (fma (sqrt x) 4.0 1.0)) (+ (/ -24.0 (sqrt x)) 6.0)))
double code(double x) {
double tmp;
if (x <= 27.0) {
tmp = fma(6.0, x, -6.0) / fma(sqrt(x), 4.0, 1.0);
} else {
tmp = (-24.0 / sqrt(x)) + 6.0;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 27.0) tmp = Float64(fma(6.0, x, -6.0) / fma(sqrt(x), 4.0, 1.0)); else tmp = Float64(Float64(-24.0 / sqrt(x)) + 6.0); end return tmp end
code[x_] := If[LessEqual[x, 27.0], N[(N[(6.0 * x + -6.0), $MachinePrecision] / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(N[(-24.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + 6.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 27:\\
\;\;\;\;\frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{-24}{\sqrt{x}} + 6\\
\end{array}
\end{array}
if x < 27Initial program 100.0%
Taylor expanded in x around inf
fp-cancel-sub-sign-invN/A
distribute-rgt-inN/A
metadata-evalN/A
associate-*l*N/A
lft-mult-inverseN/A
metadata-evalN/A
lower-fma.f64100.0
Applied rewrites100.0%
lift-+.f64N/A
lift-+.f64N/A
+-commutativeN/A
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f64100.0
Applied rewrites100.0%
Taylor expanded in x around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
if 27 < x Initial program 99.7%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites54.2%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f6497.2
Applied rewrites97.2%
Applied rewrites97.2%
(FPCore (x) :precision binary64 (if (<= x 15.0) (/ -6.0 (fma (sqrt x) 4.0 (+ 1.0 x))) (+ (/ -24.0 (sqrt x)) 6.0)))
double code(double x) {
double tmp;
if (x <= 15.0) {
tmp = -6.0 / fma(sqrt(x), 4.0, (1.0 + x));
} else {
tmp = (-24.0 / sqrt(x)) + 6.0;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 15.0) tmp = Float64(-6.0 / fma(sqrt(x), 4.0, Float64(1.0 + x))); else tmp = Float64(Float64(-24.0 / sqrt(x)) + 6.0); end return tmp end
code[x_] := If[LessEqual[x, 15.0], N[(-6.0 / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-24.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + 6.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 15:\\
\;\;\;\;\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{-24}{\sqrt{x}} + 6\\
\end{array}
\end{array}
if x < 15Initial program 100.0%
Taylor expanded in x around 0
Applied rewrites98.5%
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
lower-fma.f6498.5
lift-+.f64N/A
+-commutativeN/A
lift-+.f6498.5
Applied rewrites98.5%
if 15 < x Initial program 99.7%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites54.2%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f6497.2
Applied rewrites97.2%
Applied rewrites97.2%
(FPCore (x) :precision binary64 (/ (fma 6.0 x -6.0) (fma 4.0 (sqrt x) (+ 1.0 x))))
double code(double x) {
return fma(6.0, x, -6.0) / fma(4.0, sqrt(x), (1.0 + x));
}
function code(x) return Float64(fma(6.0, x, -6.0) / fma(4.0, sqrt(x), Float64(1.0 + x))) end
code[x_] := N[(N[(6.0 * x + -6.0), $MachinePrecision] / N[(4.0 * N[Sqrt[x], $MachinePrecision] + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}
\end{array}
Initial program 99.8%
Taylor expanded in x around inf
fp-cancel-sub-sign-invN/A
distribute-rgt-inN/A
metadata-evalN/A
associate-*l*N/A
lft-mult-inverseN/A
metadata-evalN/A
lower-fma.f6499.8
Applied rewrites99.8%
lift-+.f64N/A
lift-+.f64N/A
+-commutativeN/A
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f6499.8
Applied rewrites99.8%
(FPCore (x) :precision binary64 (if (<= x 14.0) (/ -6.0 (fma (sqrt x) 4.0 1.0)) (+ (/ -24.0 (sqrt x)) 6.0)))
double code(double x) {
double tmp;
if (x <= 14.0) {
tmp = -6.0 / fma(sqrt(x), 4.0, 1.0);
} else {
tmp = (-24.0 / sqrt(x)) + 6.0;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 14.0) tmp = Float64(-6.0 / fma(sqrt(x), 4.0, 1.0)); else tmp = Float64(Float64(-24.0 / sqrt(x)) + 6.0); end return tmp end
code[x_] := If[LessEqual[x, 14.0], N[(-6.0 / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(N[(-24.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + 6.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 14:\\
\;\;\;\;\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{-24}{\sqrt{x}} + 6\\
\end{array}
\end{array}
if x < 14Initial program 100.0%
Taylor expanded in x around 0
lower-/.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-sqrt.f6498.5
Applied rewrites98.5%
if 14 < x Initial program 99.7%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites54.2%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f6497.2
Applied rewrites97.2%
Applied rewrites97.2%
(FPCore (x) :precision binary64 (if (<= x 0.061) (fma 24.0 (sqrt x) -6.0) (+ (/ -24.0 (sqrt x)) 6.0)))
double code(double x) {
double tmp;
if (x <= 0.061) {
tmp = fma(24.0, sqrt(x), -6.0);
} else {
tmp = (-24.0 / sqrt(x)) + 6.0;
}
return tmp;
}
function code(x) tmp = 0.0 if (x <= 0.061) tmp = fma(24.0, sqrt(x), -6.0); else tmp = Float64(Float64(-24.0 / sqrt(x)) + 6.0); end return tmp end
code[x_] := If[LessEqual[x, 0.061], N[(24.0 * N[Sqrt[x], $MachinePrecision] + -6.0), $MachinePrecision], N[(N[(-24.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + 6.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.061:\\
\;\;\;\;\mathsf{fma}\left(24, \sqrt{x}, -6\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{-24}{\sqrt{x}} + 6\\
\end{array}
\end{array}
if x < 0.060999999999999999Initial program 100.0%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites100.0%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f646.7
Applied rewrites6.7%
Taylor expanded in x around 0
+-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
lower-fma.f64N/A
metadata-evalN/A
lower-sqrt.f6498.4
Applied rewrites98.4%
if 0.060999999999999999 < x Initial program 99.7%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites54.2%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f6497.2
Applied rewrites97.2%
Applied rewrites97.2%
(FPCore (x) :precision binary64 (fma 24.0 (sqrt x) -6.0))
double code(double x) {
return fma(24.0, sqrt(x), -6.0);
}
function code(x) return fma(24.0, sqrt(x), -6.0) end
code[x_] := N[(24.0 * N[Sqrt[x], $MachinePrecision] + -6.0), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(24, \sqrt{x}, -6\right)
\end{array}
Initial program 99.8%
lift-/.f64N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites74.8%
Taylor expanded in x around inf
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-/.f6456.5
Applied rewrites56.5%
Taylor expanded in x around 0
+-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
lower-fma.f64N/A
metadata-evalN/A
lower-sqrt.f6448.0
Applied rewrites48.0%
(FPCore (x) :precision binary64 (/ 6.0 (/ (+ (+ x 1.0) (* 4.0 (sqrt x))) (- x 1.0))))
double code(double x) {
return 6.0 / (((x + 1.0) + (4.0 * sqrt(x))) / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 6.0d0 / (((x + 1.0d0) + (4.0d0 * sqrt(x))) / (x - 1.0d0))
end function
public static double code(double x) {
return 6.0 / (((x + 1.0) + (4.0 * Math.sqrt(x))) / (x - 1.0));
}
def code(x): return 6.0 / (((x + 1.0) + (4.0 * math.sqrt(x))) / (x - 1.0))
function code(x) return Float64(6.0 / Float64(Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x))) / Float64(x - 1.0))) end
function tmp = code(x) tmp = 6.0 / (((x + 1.0) + (4.0 * sqrt(x))) / (x - 1.0)); end
code[x_] := N[(6.0 / N[(N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{6}{\frac{\left(x + 1\right) + 4 \cdot \sqrt{x}}{x - 1}}
\end{array}
herbie shell --seed 2024337
(FPCore (x)
:name "Data.Approximate.Numerics:blog from approximate-0.2.2.1"
:precision binary64
:alt
(! :herbie-platform default (/ 6 (/ (+ (+ x 1) (* 4 (sqrt x))) (- x 1))))
(/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))