
(FPCore (x y) :precision binary64 (let* ((t_0 (* (* y 4.0) y))) (/ (- (* x x) t_0) (+ (* x x) t_0))))
double code(double x, double y) {
double t_0 = (y * 4.0) * y;
return ((x * x) - t_0) / ((x * x) + t_0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
t_0 = (y * 4.0d0) * y
code = ((x * x) - t_0) / ((x * x) + t_0)
end function
public static double code(double x, double y) {
double t_0 = (y * 4.0) * y;
return ((x * x) - t_0) / ((x * x) + t_0);
}
def code(x, y): t_0 = (y * 4.0) * y return ((x * x) - t_0) / ((x * x) + t_0)
function code(x, y) t_0 = Float64(Float64(y * 4.0) * y) return Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)) end
function tmp = code(x, y) t_0 = (y * 4.0) * y; tmp = ((x * x) - t_0) / ((x * x) + t_0); end
code[x_, y_] := Block[{t$95$0 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(y \cdot 4\right) \cdot y\\
\frac{x \cdot x - t_0}{x \cdot x + t_0}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (let* ((t_0 (* (* y 4.0) y))) (/ (- (* x x) t_0) (+ (* x x) t_0))))
double code(double x, double y) {
double t_0 = (y * 4.0) * y;
return ((x * x) - t_0) / ((x * x) + t_0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
t_0 = (y * 4.0d0) * y
code = ((x * x) - t_0) / ((x * x) + t_0)
end function
public static double code(double x, double y) {
double t_0 = (y * 4.0) * y;
return ((x * x) - t_0) / ((x * x) + t_0);
}
def code(x, y): t_0 = (y * 4.0) * y return ((x * x) - t_0) / ((x * x) + t_0)
function code(x, y) t_0 = Float64(Float64(y * 4.0) * y) return Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)) end
function tmp = code(x, y) t_0 = (y * 4.0) * y; tmp = ((x * x) - t_0) / ((x * x) + t_0); end
code[x_, y_] := Block[{t$95$0 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(y \cdot 4\right) \cdot y\\
\frac{x \cdot x - t_0}{x \cdot x + t_0}
\end{array}
\end{array}
(FPCore (x y)
:precision binary64
(if (<= (* x x) 1e-279)
-1.0
(if (<= (* x x) 5e+110)
(/ (fma x x (* y (* y -4.0))) (fma x x (* y (* y 4.0))))
(fma (* (/ y x) (/ y x)) -8.0 1.0))))
double code(double x, double y) {
double tmp;
if ((x * x) <= 1e-279) {
tmp = -1.0;
} else if ((x * x) <= 5e+110) {
tmp = fma(x, x, (y * (y * -4.0))) / fma(x, x, (y * (y * 4.0)));
} else {
tmp = fma(((y / x) * (y / x)), -8.0, 1.0);
}
return tmp;
}
function code(x, y) tmp = 0.0 if (Float64(x * x) <= 1e-279) tmp = -1.0; elseif (Float64(x * x) <= 5e+110) tmp = Float64(fma(x, x, Float64(y * Float64(y * -4.0))) / fma(x, x, Float64(y * Float64(y * 4.0)))); else tmp = fma(Float64(Float64(y / x) * Float64(y / x)), -8.0, 1.0); end return tmp end
code[x_, y_] := If[LessEqual[N[(x * x), $MachinePrecision], 1e-279], -1.0, If[LessEqual[N[(x * x), $MachinePrecision], 5e+110], N[(N[(x * x + N[(y * N[(y * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(x * x + N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(y / x), $MachinePrecision] * N[(y / x), $MachinePrecision]), $MachinePrecision] * -8.0 + 1.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \cdot x \leq 10^{-279}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \cdot x \leq 5 \cdot 10^{+110}:\\
\;\;\;\;\frac{\mathsf{fma}\left(x, x, y \cdot \left(y \cdot -4\right)\right)}{\mathsf{fma}\left(x, x, y \cdot \left(y \cdot 4\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{y}{x} \cdot \frac{y}{x}, -8, 1\right)\\
\end{array}
\end{array}
if (*.f64 x x) < 1.00000000000000006e-279Initial program 54.7%
Taylor expanded in x around 0 85.6%
if 1.00000000000000006e-279 < (*.f64 x x) < 4.99999999999999978e110Initial program 80.2%
div-sub80.2%
+-rgt-identity80.2%
div-sub80.2%
+-rgt-identity80.2%
fma-neg80.2%
+-rgt-identity80.2%
distribute-lft-neg-in80.2%
mul0-lft80.2%
distribute-rgt-in80.2%
+-rgt-identity80.2%
distribute-rgt-neg-in80.2%
metadata-eval80.2%
fma-def80.2%
*-commutative80.2%
Simplified80.2%
if 4.99999999999999978e110 < (*.f64 x x) Initial program 34.3%
Taylor expanded in x around inf 82.8%
associate--l+82.8%
distribute-rgt-out--82.8%
metadata-eval82.8%
*-commutative82.8%
+-commutative82.8%
*-commutative82.8%
fma-def82.8%
unpow282.8%
unpow282.8%
times-frac89.1%
Simplified89.1%
Final simplification85.4%
(FPCore (x y)
:precision binary64
(let* ((t_0 (* y (* y 4.0))))
(if (<= (* x x) 1e-279)
-1.0
(if (<= (* x x) 5e+110)
(/ (- (* x x) t_0) (+ (* x x) t_0))
(fma (* (/ y x) (/ y x)) -8.0 1.0)))))
double code(double x, double y) {
double t_0 = y * (y * 4.0);
double tmp;
if ((x * x) <= 1e-279) {
tmp = -1.0;
} else if ((x * x) <= 5e+110) {
tmp = ((x * x) - t_0) / ((x * x) + t_0);
} else {
tmp = fma(((y / x) * (y / x)), -8.0, 1.0);
}
return tmp;
}
function code(x, y) t_0 = Float64(y * Float64(y * 4.0)) tmp = 0.0 if (Float64(x * x) <= 1e-279) tmp = -1.0; elseif (Float64(x * x) <= 5e+110) tmp = Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)); else tmp = fma(Float64(Float64(y / x) * Float64(y / x)), -8.0, 1.0); end return tmp end
code[x_, y_] := Block[{t$95$0 = N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(x * x), $MachinePrecision], 1e-279], -1.0, If[LessEqual[N[(x * x), $MachinePrecision], 5e+110], N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision], N[(N[(N[(y / x), $MachinePrecision] * N[(y / x), $MachinePrecision]), $MachinePrecision] * -8.0 + 1.0), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := y \cdot \left(y \cdot 4\right)\\
\mathbf{if}\;x \cdot x \leq 10^{-279}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \cdot x \leq 5 \cdot 10^{+110}:\\
\;\;\;\;\frac{x \cdot x - t_0}{x \cdot x + t_0}\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{y}{x} \cdot \frac{y}{x}, -8, 1\right)\\
\end{array}
\end{array}
if (*.f64 x x) < 1.00000000000000006e-279Initial program 54.7%
Taylor expanded in x around 0 85.6%
if 1.00000000000000006e-279 < (*.f64 x x) < 4.99999999999999978e110Initial program 80.2%
if 4.99999999999999978e110 < (*.f64 x x) Initial program 34.3%
Taylor expanded in x around inf 82.8%
associate--l+82.8%
distribute-rgt-out--82.8%
metadata-eval82.8%
*-commutative82.8%
+-commutative82.8%
*-commutative82.8%
fma-def82.8%
unpow282.8%
unpow282.8%
times-frac89.1%
Simplified89.1%
Final simplification85.4%
(FPCore (x y)
:precision binary64
(let* ((t_0 (* y (* y 4.0))))
(if (<= (* x x) 1e-279)
-1.0
(if (<= (* x x) 5e+110) (/ (- (* x x) t_0) (+ (* x x) t_0)) 1.0))))
double code(double x, double y) {
double t_0 = y * (y * 4.0);
double tmp;
if ((x * x) <= 1e-279) {
tmp = -1.0;
} else if ((x * x) <= 5e+110) {
tmp = ((x * x) - t_0) / ((x * x) + t_0);
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = y * (y * 4.0d0)
if ((x * x) <= 1d-279) then
tmp = -1.0d0
else if ((x * x) <= 5d+110) then
tmp = ((x * x) - t_0) / ((x * x) + t_0)
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = y * (y * 4.0);
double tmp;
if ((x * x) <= 1e-279) {
tmp = -1.0;
} else if ((x * x) <= 5e+110) {
tmp = ((x * x) - t_0) / ((x * x) + t_0);
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): t_0 = y * (y * 4.0) tmp = 0 if (x * x) <= 1e-279: tmp = -1.0 elif (x * x) <= 5e+110: tmp = ((x * x) - t_0) / ((x * x) + t_0) else: tmp = 1.0 return tmp
function code(x, y) t_0 = Float64(y * Float64(y * 4.0)) tmp = 0.0 if (Float64(x * x) <= 1e-279) tmp = -1.0; elseif (Float64(x * x) <= 5e+110) tmp = Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)); else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) t_0 = y * (y * 4.0); tmp = 0.0; if ((x * x) <= 1e-279) tmp = -1.0; elseif ((x * x) <= 5e+110) tmp = ((x * x) - t_0) / ((x * x) + t_0); else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(x * x), $MachinePrecision], 1e-279], -1.0, If[LessEqual[N[(x * x), $MachinePrecision], 5e+110], N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision], 1.0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := y \cdot \left(y \cdot 4\right)\\
\mathbf{if}\;x \cdot x \leq 10^{-279}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \cdot x \leq 5 \cdot 10^{+110}:\\
\;\;\;\;\frac{x \cdot x - t_0}{x \cdot x + t_0}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if (*.f64 x x) < 1.00000000000000006e-279Initial program 54.7%
Taylor expanded in x around 0 85.6%
if 1.00000000000000006e-279 < (*.f64 x x) < 4.99999999999999978e110Initial program 80.2%
if 4.99999999999999978e110 < (*.f64 x x) Initial program 34.3%
Taylor expanded in x around inf 88.5%
Final simplification85.2%
(FPCore (x y) :precision binary64 (if (<= (* x x) 2e-8) -1.0 1.0))
double code(double x, double y) {
double tmp;
if ((x * x) <= 2e-8) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x * x) <= 2d-8) then
tmp = -1.0d0
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x * x) <= 2e-8) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x * x) <= 2e-8: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (Float64(x * x) <= 2e-8) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x * x) <= 2e-8) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[N[(x * x), $MachinePrecision], 2e-8], -1.0, 1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \cdot x \leq 2 \cdot 10^{-8}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if (*.f64 x x) < 2e-8Initial program 65.6%
Taylor expanded in x around 0 74.6%
if 2e-8 < (*.f64 x x) Initial program 42.2%
Taylor expanded in x around inf 82.9%
Final simplification78.7%
(FPCore (x y) :precision binary64 -1.0)
double code(double x, double y) {
return -1.0;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -1.0d0
end function
public static double code(double x, double y) {
return -1.0;
}
def code(x, y): return -1.0
function code(x, y) return -1.0 end
function tmp = code(x, y) tmp = -1.0; end
code[x_, y_] := -1.0
\begin{array}{l}
\\
-1
\end{array}
Initial program 53.9%
Taylor expanded in x around 0 46.6%
Final simplification46.6%
(FPCore (x y)
:precision binary64
(let* ((t_0 (* (* y y) 4.0))
(t_1 (+ (* x x) t_0))
(t_2 (/ t_0 t_1))
(t_3 (* (* y 4.0) y)))
(if (< (/ (- (* x x) t_3) (+ (* x x) t_3)) 0.9743233849626781)
(- (/ (* x x) t_1) t_2)
(- (pow (/ x (sqrt t_1)) 2.0) t_2))))
double code(double x, double y) {
double t_0 = (y * y) * 4.0;
double t_1 = (x * x) + t_0;
double t_2 = t_0 / t_1;
double t_3 = (y * 4.0) * y;
double tmp;
if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781) {
tmp = ((x * x) / t_1) - t_2;
} else {
tmp = pow((x / sqrt(t_1)), 2.0) - t_2;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: t_1
real(8) :: t_2
real(8) :: t_3
real(8) :: tmp
t_0 = (y * y) * 4.0d0
t_1 = (x * x) + t_0
t_2 = t_0 / t_1
t_3 = (y * 4.0d0) * y
if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781d0) then
tmp = ((x * x) / t_1) - t_2
else
tmp = ((x / sqrt(t_1)) ** 2.0d0) - t_2
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = (y * y) * 4.0;
double t_1 = (x * x) + t_0;
double t_2 = t_0 / t_1;
double t_3 = (y * 4.0) * y;
double tmp;
if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781) {
tmp = ((x * x) / t_1) - t_2;
} else {
tmp = Math.pow((x / Math.sqrt(t_1)), 2.0) - t_2;
}
return tmp;
}
def code(x, y): t_0 = (y * y) * 4.0 t_1 = (x * x) + t_0 t_2 = t_0 / t_1 t_3 = (y * 4.0) * y tmp = 0 if (((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781: tmp = ((x * x) / t_1) - t_2 else: tmp = math.pow((x / math.sqrt(t_1)), 2.0) - t_2 return tmp
function code(x, y) t_0 = Float64(Float64(y * y) * 4.0) t_1 = Float64(Float64(x * x) + t_0) t_2 = Float64(t_0 / t_1) t_3 = Float64(Float64(y * 4.0) * y) tmp = 0.0 if (Float64(Float64(Float64(x * x) - t_3) / Float64(Float64(x * x) + t_3)) < 0.9743233849626781) tmp = Float64(Float64(Float64(x * x) / t_1) - t_2); else tmp = Float64((Float64(x / sqrt(t_1)) ^ 2.0) - t_2); end return tmp end
function tmp_2 = code(x, y) t_0 = (y * y) * 4.0; t_1 = (x * x) + t_0; t_2 = t_0 / t_1; t_3 = (y * 4.0) * y; tmp = 0.0; if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781) tmp = ((x * x) / t_1) - t_2; else tmp = ((x / sqrt(t_1)) ^ 2.0) - t_2; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(N[(y * y), $MachinePrecision] * 4.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$0 / t$95$1), $MachinePrecision]}, Block[{t$95$3 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, If[Less[N[(N[(N[(x * x), $MachinePrecision] - t$95$3), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$3), $MachinePrecision]), $MachinePrecision], 0.9743233849626781], N[(N[(N[(x * x), $MachinePrecision] / t$95$1), $MachinePrecision] - t$95$2), $MachinePrecision], N[(N[Power[N[(x / N[Sqrt[t$95$1], $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] - t$95$2), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(y \cdot y\right) \cdot 4\\
t_1 := x \cdot x + t_0\\
t_2 := \frac{t_0}{t_1}\\
t_3 := \left(y \cdot 4\right) \cdot y\\
\mathbf{if}\;\frac{x \cdot x - t_3}{x \cdot x + t_3} < 0.9743233849626781:\\
\;\;\;\;\frac{x \cdot x}{t_1} - t_2\\
\mathbf{else}:\\
\;\;\;\;{\left(\frac{x}{\sqrt{t_1}}\right)}^{2} - t_2\\
\end{array}
\end{array}
herbie shell --seed 2023221
(FPCore (x y)
:name "Diagrams.TwoD.Arc:arcBetween from diagrams-lib-1.3.0.3"
:precision binary64
:herbie-target
(if (< (/ (- (* x x) (* (* y 4.0) y)) (+ (* x x) (* (* y 4.0) y))) 0.9743233849626781) (- (/ (* x x) (+ (* x x) (* (* y y) 4.0))) (/ (* (* y y) 4.0) (+ (* x x) (* (* y y) 4.0)))) (- (pow (/ x (sqrt (+ (* x x) (* (* y y) 4.0)))) 2.0) (/ (* (* y y) 4.0) (+ (* x x) (* (* y y) 4.0)))))
(/ (- (* x x) (* (* y 4.0) y)) (+ (* x x) (* (* y 4.0) y))))