
(FPCore (p x) :precision binary64 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))
double code(double p, double x) {
return sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
}
real(8) function code(p, x)
real(8), intent (in) :: p
real(8), intent (in) :: x
code = sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x)))))))
end function
public static double code(double p, double x) {
return Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x)))))));
}
def code(p, x): return math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x)))))))
function code(p, x) return sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x))))))) end
function tmp = code(p, x) tmp = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))); end
code[p_, x_] := N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (p x) :precision binary64 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))
double code(double p, double x) {
return sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
}
real(8) function code(p, x)
real(8), intent (in) :: p
real(8), intent (in) :: x
code = sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x)))))))
end function
public static double code(double p, double x) {
return Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x)))))));
}
def code(p, x): return math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x)))))))
function code(p, x) return sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x))))))) end
function tmp = code(p, x) tmp = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))); end
code[p_, x_] := N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}
\end{array}
p_m = (fabs.f64 p) (FPCore (p_m x) :precision binary64 (if (<= (/ x (sqrt (+ (* p_m (* 4.0 p_m)) (* x x)))) -0.9) (/ p_m (- x)) (sqrt (* 0.5 (+ -1.0 (+ 2.0 (/ x (hypot x (* p_m 2.0)))))))))
p_m = fabs(p);
double code(double p_m, double x) {
double tmp;
if ((x / sqrt(((p_m * (4.0 * p_m)) + (x * x)))) <= -0.9) {
tmp = p_m / -x;
} else {
tmp = sqrt((0.5 * (-1.0 + (2.0 + (x / hypot(x, (p_m * 2.0)))))));
}
return tmp;
}
p_m = Math.abs(p);
public static double code(double p_m, double x) {
double tmp;
if ((x / Math.sqrt(((p_m * (4.0 * p_m)) + (x * x)))) <= -0.9) {
tmp = p_m / -x;
} else {
tmp = Math.sqrt((0.5 * (-1.0 + (2.0 + (x / Math.hypot(x, (p_m * 2.0)))))));
}
return tmp;
}
p_m = math.fabs(p) def code(p_m, x): tmp = 0 if (x / math.sqrt(((p_m * (4.0 * p_m)) + (x * x)))) <= -0.9: tmp = p_m / -x else: tmp = math.sqrt((0.5 * (-1.0 + (2.0 + (x / math.hypot(x, (p_m * 2.0))))))) return tmp
p_m = abs(p) function code(p_m, x) tmp = 0.0 if (Float64(x / sqrt(Float64(Float64(p_m * Float64(4.0 * p_m)) + Float64(x * x)))) <= -0.9) tmp = Float64(p_m / Float64(-x)); else tmp = sqrt(Float64(0.5 * Float64(-1.0 + Float64(2.0 + Float64(x / hypot(x, Float64(p_m * 2.0))))))); end return tmp end
p_m = abs(p); function tmp_2 = code(p_m, x) tmp = 0.0; if ((x / sqrt(((p_m * (4.0 * p_m)) + (x * x)))) <= -0.9) tmp = p_m / -x; else tmp = sqrt((0.5 * (-1.0 + (2.0 + (x / hypot(x, (p_m * 2.0))))))); end tmp_2 = tmp; end
p_m = N[Abs[p], $MachinePrecision] code[p$95$m_, x_] := If[LessEqual[N[(x / N[Sqrt[N[(N[(p$95$m * N[(4.0 * p$95$m), $MachinePrecision]), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], -0.9], N[(p$95$m / (-x)), $MachinePrecision], N[Sqrt[N[(0.5 * N[(-1.0 + N[(2.0 + N[(x / N[Sqrt[x ^ 2 + N[(p$95$m * 2.0), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
p_m = \left|p\right|
\\
\begin{array}{l}
\mathbf{if}\;\frac{x}{\sqrt{p\_m \cdot \left(4 \cdot p\_m\right) + x \cdot x}} \leq -0.9:\\
\;\;\;\;\frac{p\_m}{-x}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{0.5 \cdot \left(-1 + \left(2 + \frac{x}{\mathsf{hypot}\left(x, p\_m \cdot 2\right)}\right)\right)}\\
\end{array}
\end{array}
if (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < -0.900000000000000022Initial program 18.8%
Taylor expanded in x around -inf 55.6%
mul-1-neg55.6%
Simplified55.6%
distribute-neg-frac55.6%
sqrt-unprod56.4%
metadata-eval56.4%
metadata-eval56.4%
*-rgt-identity56.4%
Applied egg-rr56.4%
if -0.900000000000000022 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) Initial program 100.0%
expm1-log1p-u99.4%
expm1-undefine99.4%
+-commutative99.4%
add-sqr-sqrt99.4%
hypot-define99.4%
associate-*l*99.4%
sqrt-prod99.4%
metadata-eval99.4%
sqrt-unprod49.5%
add-sqr-sqrt99.4%
Applied egg-rr99.4%
sub-neg99.4%
metadata-eval99.4%
+-commutative99.4%
log1p-undefine100.0%
rem-exp-log100.0%
associate-+r+100.0%
metadata-eval100.0%
Simplified100.0%
Final simplification91.7%
p_m = (fabs.f64 p) (FPCore (p_m x) :precision binary64 (if (or (<= x -4.8e+47) (and (not (<= x -1.45e-23)) (<= x -9e-55))) (/ p_m (- x)) (sqrt (+ 0.5 (/ (* x 0.5) (hypot x (* p_m 2.0)))))))
p_m = fabs(p);
double code(double p_m, double x) {
double tmp;
if ((x <= -4.8e+47) || (!(x <= -1.45e-23) && (x <= -9e-55))) {
tmp = p_m / -x;
} else {
tmp = sqrt((0.5 + ((x * 0.5) / hypot(x, (p_m * 2.0)))));
}
return tmp;
}
p_m = Math.abs(p);
public static double code(double p_m, double x) {
double tmp;
if ((x <= -4.8e+47) || (!(x <= -1.45e-23) && (x <= -9e-55))) {
tmp = p_m / -x;
} else {
tmp = Math.sqrt((0.5 + ((x * 0.5) / Math.hypot(x, (p_m * 2.0)))));
}
return tmp;
}
p_m = math.fabs(p) def code(p_m, x): tmp = 0 if (x <= -4.8e+47) or (not (x <= -1.45e-23) and (x <= -9e-55)): tmp = p_m / -x else: tmp = math.sqrt((0.5 + ((x * 0.5) / math.hypot(x, (p_m * 2.0))))) return tmp
p_m = abs(p) function code(p_m, x) tmp = 0.0 if ((x <= -4.8e+47) || (!(x <= -1.45e-23) && (x <= -9e-55))) tmp = Float64(p_m / Float64(-x)); else tmp = sqrt(Float64(0.5 + Float64(Float64(x * 0.5) / hypot(x, Float64(p_m * 2.0))))); end return tmp end
p_m = abs(p); function tmp_2 = code(p_m, x) tmp = 0.0; if ((x <= -4.8e+47) || (~((x <= -1.45e-23)) && (x <= -9e-55))) tmp = p_m / -x; else tmp = sqrt((0.5 + ((x * 0.5) / hypot(x, (p_m * 2.0))))); end tmp_2 = tmp; end
p_m = N[Abs[p], $MachinePrecision] code[p$95$m_, x_] := If[Or[LessEqual[x, -4.8e+47], And[N[Not[LessEqual[x, -1.45e-23]], $MachinePrecision], LessEqual[x, -9e-55]]], N[(p$95$m / (-x)), $MachinePrecision], N[Sqrt[N[(0.5 + N[(N[(x * 0.5), $MachinePrecision] / N[Sqrt[x ^ 2 + N[(p$95$m * 2.0), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
p_m = \left|p\right|
\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.8 \cdot 10^{+47} \lor \neg \left(x \leq -1.45 \cdot 10^{-23}\right) \land x \leq -9 \cdot 10^{-55}:\\
\;\;\;\;\frac{p\_m}{-x}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{0.5 + \frac{x \cdot 0.5}{\mathsf{hypot}\left(x, p\_m \cdot 2\right)}}\\
\end{array}
\end{array}
if x < -4.80000000000000037e47 or -1.4500000000000001e-23 < x < -8.99999999999999941e-55Initial program 48.9%
Taylor expanded in x around -inf 40.3%
mul-1-neg40.3%
Simplified40.3%
distribute-neg-frac40.3%
sqrt-unprod40.9%
metadata-eval40.9%
metadata-eval40.9%
*-rgt-identity40.9%
Applied egg-rr40.9%
if -4.80000000000000037e47 < x < -1.4500000000000001e-23 or -8.99999999999999941e-55 < x Initial program 94.4%
+-commutative94.4%
distribute-lft-in94.4%
associate-*r/94.4%
+-commutative94.4%
add-sqr-sqrt94.4%
hypot-define94.4%
associate-*l*94.4%
sqrt-prod94.4%
metadata-eval94.4%
sqrt-unprod47.6%
add-sqr-sqrt94.4%
metadata-eval94.4%
Applied egg-rr94.4%
Final simplification82.7%
p_m = (fabs.f64 p) (FPCore (p_m x) :precision binary64 (if (<= p_m 7e-115) 1.0 (if (<= p_m 5.4e-109) (/ p_m (- x)) (if (<= p_m 1.28e-48) 1.0 (sqrt 0.5)))))
p_m = fabs(p);
double code(double p_m, double x) {
double tmp;
if (p_m <= 7e-115) {
tmp = 1.0;
} else if (p_m <= 5.4e-109) {
tmp = p_m / -x;
} else if (p_m <= 1.28e-48) {
tmp = 1.0;
} else {
tmp = sqrt(0.5);
}
return tmp;
}
p_m = abs(p)
real(8) function code(p_m, x)
real(8), intent (in) :: p_m
real(8), intent (in) :: x
real(8) :: tmp
if (p_m <= 7d-115) then
tmp = 1.0d0
else if (p_m <= 5.4d-109) then
tmp = p_m / -x
else if (p_m <= 1.28d-48) then
tmp = 1.0d0
else
tmp = sqrt(0.5d0)
end if
code = tmp
end function
p_m = Math.abs(p);
public static double code(double p_m, double x) {
double tmp;
if (p_m <= 7e-115) {
tmp = 1.0;
} else if (p_m <= 5.4e-109) {
tmp = p_m / -x;
} else if (p_m <= 1.28e-48) {
tmp = 1.0;
} else {
tmp = Math.sqrt(0.5);
}
return tmp;
}
p_m = math.fabs(p) def code(p_m, x): tmp = 0 if p_m <= 7e-115: tmp = 1.0 elif p_m <= 5.4e-109: tmp = p_m / -x elif p_m <= 1.28e-48: tmp = 1.0 else: tmp = math.sqrt(0.5) return tmp
p_m = abs(p) function code(p_m, x) tmp = 0.0 if (p_m <= 7e-115) tmp = 1.0; elseif (p_m <= 5.4e-109) tmp = Float64(p_m / Float64(-x)); elseif (p_m <= 1.28e-48) tmp = 1.0; else tmp = sqrt(0.5); end return tmp end
p_m = abs(p); function tmp_2 = code(p_m, x) tmp = 0.0; if (p_m <= 7e-115) tmp = 1.0; elseif (p_m <= 5.4e-109) tmp = p_m / -x; elseif (p_m <= 1.28e-48) tmp = 1.0; else tmp = sqrt(0.5); end tmp_2 = tmp; end
p_m = N[Abs[p], $MachinePrecision] code[p$95$m_, x_] := If[LessEqual[p$95$m, 7e-115], 1.0, If[LessEqual[p$95$m, 5.4e-109], N[(p$95$m / (-x)), $MachinePrecision], If[LessEqual[p$95$m, 1.28e-48], 1.0, N[Sqrt[0.5], $MachinePrecision]]]]
\begin{array}{l}
p_m = \left|p\right|
\\
\begin{array}{l}
\mathbf{if}\;p\_m \leq 7 \cdot 10^{-115}:\\
\;\;\;\;1\\
\mathbf{elif}\;p\_m \leq 5.4 \cdot 10^{-109}:\\
\;\;\;\;\frac{p\_m}{-x}\\
\mathbf{elif}\;p\_m \leq 1.28 \cdot 10^{-48}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;\sqrt{0.5}\\
\end{array}
\end{array}
if p < 7.0000000000000004e-115 or 5.4000000000000001e-109 < p < 1.28000000000000001e-48Initial program 83.6%
+-commutative83.6%
distribute-lft-in83.6%
associate-*r/83.6%
+-commutative83.6%
add-sqr-sqrt83.6%
hypot-define83.6%
associate-*l*83.6%
sqrt-prod83.6%
metadata-eval83.6%
sqrt-unprod21.6%
add-sqr-sqrt83.6%
metadata-eval83.6%
Applied egg-rr83.6%
Taylor expanded in x around inf 48.6%
if 7.0000000000000004e-115 < p < 5.4000000000000001e-109Initial program 4.3%
Taylor expanded in x around -inf 98.0%
mul-1-neg98.0%
Simplified98.0%
distribute-neg-frac98.0%
sqrt-unprod100.0%
metadata-eval100.0%
metadata-eval100.0%
*-rgt-identity100.0%
Applied egg-rr100.0%
if 1.28000000000000001e-48 < p Initial program 88.6%
Taylor expanded in x around 0 82.3%
Final simplification59.0%
p_m = (fabs.f64 p) (FPCore (p_m x) :precision binary64 (if (<= x -3.2e-103) (/ p_m (- x)) 1.0))
p_m = fabs(p);
double code(double p_m, double x) {
double tmp;
if (x <= -3.2e-103) {
tmp = p_m / -x;
} else {
tmp = 1.0;
}
return tmp;
}
p_m = abs(p)
real(8) function code(p_m, x)
real(8), intent (in) :: p_m
real(8), intent (in) :: x
real(8) :: tmp
if (x <= (-3.2d-103)) then
tmp = p_m / -x
else
tmp = 1.0d0
end if
code = tmp
end function
p_m = Math.abs(p);
public static double code(double p_m, double x) {
double tmp;
if (x <= -3.2e-103) {
tmp = p_m / -x;
} else {
tmp = 1.0;
}
return tmp;
}
p_m = math.fabs(p) def code(p_m, x): tmp = 0 if x <= -3.2e-103: tmp = p_m / -x else: tmp = 1.0 return tmp
p_m = abs(p) function code(p_m, x) tmp = 0.0 if (x <= -3.2e-103) tmp = Float64(p_m / Float64(-x)); else tmp = 1.0; end return tmp end
p_m = abs(p); function tmp_2 = code(p_m, x) tmp = 0.0; if (x <= -3.2e-103) tmp = p_m / -x; else tmp = 1.0; end tmp_2 = tmp; end
p_m = N[Abs[p], $MachinePrecision] code[p$95$m_, x_] := If[LessEqual[x, -3.2e-103], N[(p$95$m / (-x)), $MachinePrecision], 1.0]
\begin{array}{l}
p_m = \left|p\right|
\\
\begin{array}{l}
\mathbf{if}\;x \leq -3.2 \cdot 10^{-103}:\\
\;\;\;\;\frac{p\_m}{-x}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -3.19999999999999976e-103Initial program 58.2%
Taylor expanded in x around -inf 29.7%
mul-1-neg29.7%
Simplified29.7%
distribute-neg-frac29.7%
sqrt-unprod30.2%
metadata-eval30.2%
metadata-eval30.2%
*-rgt-identity30.2%
Applied egg-rr30.2%
if -3.19999999999999976e-103 < x Initial program 99.4%
+-commutative99.4%
distribute-lft-in99.4%
associate-*r/99.4%
+-commutative99.4%
add-sqr-sqrt99.4%
hypot-define99.4%
associate-*l*99.4%
sqrt-prod99.4%
metadata-eval99.4%
sqrt-unprod49.1%
add-sqr-sqrt99.4%
metadata-eval99.4%
Applied egg-rr99.4%
Taylor expanded in x around inf 56.7%
Final simplification47.1%
p_m = (fabs.f64 p) (FPCore (p_m x) :precision binary64 1.0)
p_m = fabs(p);
double code(double p_m, double x) {
return 1.0;
}
p_m = abs(p)
real(8) function code(p_m, x)
real(8), intent (in) :: p_m
real(8), intent (in) :: x
code = 1.0d0
end function
p_m = Math.abs(p);
public static double code(double p_m, double x) {
return 1.0;
}
p_m = math.fabs(p) def code(p_m, x): return 1.0
p_m = abs(p) function code(p_m, x) return 1.0 end
p_m = abs(p); function tmp = code(p_m, x) tmp = 1.0; end
p_m = N[Abs[p], $MachinePrecision] code[p$95$m_, x_] := 1.0
\begin{array}{l}
p_m = \left|p\right|
\\
1
\end{array}
Initial program 84.4%
+-commutative84.4%
distribute-lft-in84.4%
associate-*r/84.4%
+-commutative84.4%
add-sqr-sqrt84.4%
hypot-define84.4%
associate-*l*84.4%
sqrt-prod84.4%
metadata-eval84.4%
sqrt-unprod41.4%
add-sqr-sqrt84.4%
metadata-eval84.4%
Applied egg-rr84.4%
Taylor expanded in x around inf 40.5%
(FPCore (p x) :precision binary64 (sqrt (+ 0.5 (/ (copysign 0.5 x) (hypot 1.0 (/ (* 2.0 p) x))))))
double code(double p, double x) {
return sqrt((0.5 + (copysign(0.5, x) / hypot(1.0, ((2.0 * p) / x)))));
}
public static double code(double p, double x) {
return Math.sqrt((0.5 + (Math.copySign(0.5, x) / Math.hypot(1.0, ((2.0 * p) / x)))));
}
def code(p, x): return math.sqrt((0.5 + (math.copysign(0.5, x) / math.hypot(1.0, ((2.0 * p) / x)))))
function code(p, x) return sqrt(Float64(0.5 + Float64(copysign(0.5, x) / hypot(1.0, Float64(Float64(2.0 * p) / x))))) end
function tmp = code(p, x) tmp = sqrt((0.5 + ((sign(x) * abs(0.5)) / hypot(1.0, ((2.0 * p) / x))))); end
code[p_, x_] := N[Sqrt[N[(0.5 + N[(N[With[{TMP1 = Abs[0.5], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] / N[Sqrt[1.0 ^ 2 + N[(N[(2.0 * p), $MachinePrecision] / x), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.5 + \frac{\mathsf{copysign}\left(0.5, x\right)}{\mathsf{hypot}\left(1, \frac{2 \cdot p}{x}\right)}}
\end{array}
herbie shell --seed 2024110
(FPCore (p x)
:name "Given's Rotation SVD example"
:precision binary64
:pre (and (< 1e-150 (fabs x)) (< (fabs x) 1e+150))
:alt
(sqrt (+ 0.5 (/ (copysign 0.5 x) (hypot 1.0 (/ (* 2.0 p) x)))))
(sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))