
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (-b + sqrt(((b * b) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (-b + sqrt(((b * b) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}
(FPCore (a b c) :precision binary64 (fma -0.5625 (/ (pow c 3.0) (/ (pow b 5.0) (* a a))) (fma -0.16666666666666666 (/ (pow (* c a) 4.0) (/ (* a (pow b 7.0)) 6.328125)) (fma -0.5 (/ c b) (* -0.375 (/ (* c (* c a)) (pow b 3.0)))))))
double code(double a, double b, double c) {
return fma(-0.5625, (pow(c, 3.0) / (pow(b, 5.0) / (a * a))), fma(-0.16666666666666666, (pow((c * a), 4.0) / ((a * pow(b, 7.0)) / 6.328125)), fma(-0.5, (c / b), (-0.375 * ((c * (c * a)) / pow(b, 3.0))))));
}
function code(a, b, c) return fma(-0.5625, Float64((c ^ 3.0) / Float64((b ^ 5.0) / Float64(a * a))), fma(-0.16666666666666666, Float64((Float64(c * a) ^ 4.0) / Float64(Float64(a * (b ^ 7.0)) / 6.328125)), fma(-0.5, Float64(c / b), Float64(-0.375 * Float64(Float64(c * Float64(c * a)) / (b ^ 3.0)))))) end
code[a_, b_, c_] := N[(-0.5625 * N[(N[Power[c, 3.0], $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.16666666666666666 * N[(N[Power[N[(c * a), $MachinePrecision], 4.0], $MachinePrecision] / N[(N[(a * N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision] / 6.328125), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * N[(c / b), $MachinePrecision] + N[(-0.375 * N[(N[(c * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.5625, \frac{{c}^{3}}{\frac{{b}^{5}}{a \cdot a}}, \mathsf{fma}\left(-0.16666666666666666, \frac{{\left(c \cdot a\right)}^{4}}{\frac{a \cdot {b}^{7}}{6.328125}}, \mathsf{fma}\left(-0.5, \frac{c}{b}, -0.375 \cdot \frac{c \cdot \left(c \cdot a\right)}{{b}^{3}}\right)\right)\right)
\end{array}
Initial program 33.0%
neg-sub033.0%
associate-+l-33.0%
sub0-neg33.0%
neg-mul-133.0%
associate-*r/33.0%
*-commutative33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
Simplified33.0%
add-sqr-sqrt33.0%
sqrt-unprod33.0%
frac-times33.0%
metadata-eval33.0%
Applied egg-rr33.0%
Taylor expanded in b around inf 95.3%
Simplified95.3%
Final simplification95.3%
(FPCore (a b c) :precision binary64 (fma -0.5625 (* a (/ (* (pow c 3.0) a) (pow b 5.0))) (fma -0.16666666666666666 (* (/ (pow (* c a) 4.0) a) (/ 6.328125 (pow b 7.0))) (fma c (/ -0.5 b) (* (* a -0.375) (/ (* c c) (pow b 3.0)))))))
double code(double a, double b, double c) {
return fma(-0.5625, (a * ((pow(c, 3.0) * a) / pow(b, 5.0))), fma(-0.16666666666666666, ((pow((c * a), 4.0) / a) * (6.328125 / pow(b, 7.0))), fma(c, (-0.5 / b), ((a * -0.375) * ((c * c) / pow(b, 3.0))))));
}
function code(a, b, c) return fma(-0.5625, Float64(a * Float64(Float64((c ^ 3.0) * a) / (b ^ 5.0))), fma(-0.16666666666666666, Float64(Float64((Float64(c * a) ^ 4.0) / a) * Float64(6.328125 / (b ^ 7.0))), fma(c, Float64(-0.5 / b), Float64(Float64(a * -0.375) * Float64(Float64(c * c) / (b ^ 3.0)))))) end
code[a_, b_, c_] := N[(-0.5625 * N[(a * N[(N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.16666666666666666 * N[(N[(N[Power[N[(c * a), $MachinePrecision], 4.0], $MachinePrecision] / a), $MachinePrecision] * N[(6.328125 / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(c * N[(-0.5 / b), $MachinePrecision] + N[(N[(a * -0.375), $MachinePrecision] * N[(N[(c * c), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.5625, a \cdot \frac{{c}^{3} \cdot a}{{b}^{5}}, \mathsf{fma}\left(-0.16666666666666666, \frac{{\left(c \cdot a\right)}^{4}}{a} \cdot \frac{6.328125}{{b}^{7}}, \mathsf{fma}\left(c, \frac{-0.5}{b}, \left(a \cdot -0.375\right) \cdot \frac{c \cdot c}{{b}^{3}}\right)\right)\right)
\end{array}
Initial program 33.0%
neg-sub033.0%
associate-+l-33.0%
sub0-neg33.0%
neg-mul-133.0%
associate-*r/33.0%
*-commutative33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
Simplified33.0%
add-sqr-sqrt33.0%
sqrt-unprod33.0%
frac-times33.0%
metadata-eval33.0%
Applied egg-rr33.0%
add-log-exp25.1%
sqrt-div25.1%
metadata-eval25.1%
Applied egg-rr25.1%
Taylor expanded in b around inf 95.3%
Simplified95.2%
Taylor expanded in c around 0 95.2%
+-commutative95.2%
distribute-rgt-out95.2%
associate-*r*95.2%
times-frac95.2%
Simplified95.2%
Final simplification95.2%
(FPCore (a b c) :precision binary64 (fma -0.5625 (* a (/ (* (pow c 3.0) a) (pow b 5.0))) (fma c (/ -0.5 b) (* (* a -0.375) (/ (* c c) (pow b 3.0))))))
double code(double a, double b, double c) {
return fma(-0.5625, (a * ((pow(c, 3.0) * a) / pow(b, 5.0))), fma(c, (-0.5 / b), ((a * -0.375) * ((c * c) / pow(b, 3.0)))));
}
function code(a, b, c) return fma(-0.5625, Float64(a * Float64(Float64((c ^ 3.0) * a) / (b ^ 5.0))), fma(c, Float64(-0.5 / b), Float64(Float64(a * -0.375) * Float64(Float64(c * c) / (b ^ 3.0))))) end
code[a_, b_, c_] := N[(-0.5625 * N[(a * N[(N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(c * N[(-0.5 / b), $MachinePrecision] + N[(N[(a * -0.375), $MachinePrecision] * N[(N[(c * c), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.5625, a \cdot \frac{{c}^{3} \cdot a}{{b}^{5}}, \mathsf{fma}\left(c, \frac{-0.5}{b}, \left(a \cdot -0.375\right) \cdot \frac{c \cdot c}{{b}^{3}}\right)\right)
\end{array}
Initial program 33.0%
neg-sub033.0%
associate-+l-33.0%
sub0-neg33.0%
neg-mul-133.0%
associate-*r/33.0%
*-commutative33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
Simplified33.0%
add-sqr-sqrt33.0%
sqrt-unprod33.0%
frac-times33.0%
metadata-eval33.0%
Applied egg-rr33.0%
add-log-exp25.1%
sqrt-div25.1%
metadata-eval25.1%
Applied egg-rr25.1%
Taylor expanded in b around inf 93.9%
fma-def93.9%
associate-*l/93.9%
unpow293.9%
associate-*r*93.9%
*-commutative93.9%
associate-*l/93.9%
associate-*r/93.9%
*-commutative93.9%
associate-*r/93.7%
fma-def93.8%
*-commutative93.8%
associate-*r/93.8%
associate-*r*93.8%
unpow293.8%
Simplified93.8%
Final simplification93.8%
(FPCore (a b c) :precision binary64 (fma -0.5625 (/ (pow c 3.0) (/ (pow b 5.0) (* a a))) (fma -0.375 (/ (* c c) (/ (pow b 3.0) a)) (/ (* c -0.5) b))))
double code(double a, double b, double c) {
return fma(-0.5625, (pow(c, 3.0) / (pow(b, 5.0) / (a * a))), fma(-0.375, ((c * c) / (pow(b, 3.0) / a)), ((c * -0.5) / b)));
}
function code(a, b, c) return fma(-0.5625, Float64((c ^ 3.0) / Float64((b ^ 5.0) / Float64(a * a))), fma(-0.375, Float64(Float64(c * c) / Float64((b ^ 3.0) / a)), Float64(Float64(c * -0.5) / b))) end
code[a_, b_, c_] := N[(-0.5625 * N[(N[Power[c, 3.0], $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(c * c), $MachinePrecision] / N[(N[Power[b, 3.0], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.5625, \frac{{c}^{3}}{\frac{{b}^{5}}{a \cdot a}}, \mathsf{fma}\left(-0.375, \frac{c \cdot c}{\frac{{b}^{3}}{a}}, \frac{c \cdot -0.5}{b}\right)\right)
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
*-commutative33.0%
associate-/r*33.0%
associate-*l/33.0%
Simplified33.0%
Taylor expanded in b around inf 93.9%
fma-def93.9%
associate-/l*93.9%
unpow293.9%
+-commutative93.9%
fma-def93.9%
associate-/l*93.9%
unpow293.9%
associate-*r/93.9%
Simplified93.9%
Final simplification93.9%
(FPCore (a b c) :precision binary64 (fma -0.375 (/ (* c c) (/ (pow b 3.0) a)) (/ (* c -0.5) b)))
double code(double a, double b, double c) {
return fma(-0.375, ((c * c) / (pow(b, 3.0) / a)), ((c * -0.5) / b));
}
function code(a, b, c) return fma(-0.375, Float64(Float64(c * c) / Float64((b ^ 3.0) / a)), Float64(Float64(c * -0.5) / b)) end
code[a_, b_, c_] := N[(-0.375 * N[(N[(c * c), $MachinePrecision] / N[(N[Power[b, 3.0], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.375, \frac{c \cdot c}{\frac{{b}^{3}}{a}}, \frac{c \cdot -0.5}{b}\right)
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
*-commutative33.0%
associate-/r*33.0%
associate-*l/33.0%
Simplified33.0%
Taylor expanded in b around inf 90.9%
+-commutative90.9%
fma-def90.9%
associate-/l*90.9%
unpow290.9%
associate-*r/90.9%
Simplified90.9%
Final simplification90.9%
(FPCore (a b c) :precision binary64 (+ (* -0.375 (* a (/ (* c c) (pow b 3.0)))) (/ -0.5 (/ b c))))
double code(double a, double b, double c) {
return (-0.375 * (a * ((c * c) / pow(b, 3.0)))) + (-0.5 / (b / c));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = ((-0.375d0) * (a * ((c * c) / (b ** 3.0d0)))) + ((-0.5d0) / (b / c))
end function
public static double code(double a, double b, double c) {
return (-0.375 * (a * ((c * c) / Math.pow(b, 3.0)))) + (-0.5 / (b / c));
}
def code(a, b, c): return (-0.375 * (a * ((c * c) / math.pow(b, 3.0)))) + (-0.5 / (b / c))
function code(a, b, c) return Float64(Float64(-0.375 * Float64(a * Float64(Float64(c * c) / (b ^ 3.0)))) + Float64(-0.5 / Float64(b / c))) end
function tmp = code(a, b, c) tmp = (-0.375 * (a * ((c * c) / (b ^ 3.0)))) + (-0.5 / (b / c)); end
code[a_, b_, c_] := N[(N[(-0.375 * N[(a * N[(N[(c * c), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5 / N[(b / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.375 \cdot \left(a \cdot \frac{c \cdot c}{{b}^{3}}\right) + \frac{-0.5}{\frac{b}{c}}
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
*-commutative33.0%
associate-/r*33.0%
associate-*l/33.0%
Simplified33.0%
Taylor expanded in b around inf 90.9%
+-commutative90.9%
fma-def90.9%
associate-/l*90.9%
unpow290.9%
associate-*r/90.9%
Simplified90.9%
fma-udef90.9%
associate-/r/90.9%
associate-/l*90.7%
Applied egg-rr90.7%
Final simplification90.7%
(FPCore (a b c) :precision binary64 (* c (/ -0.5 b)))
double code(double a, double b, double c) {
return c * (-0.5 / b);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = c * ((-0.5d0) / b)
end function
public static double code(double a, double b, double c) {
return c * (-0.5 / b);
}
def code(a, b, c): return c * (-0.5 / b)
function code(a, b, c) return Float64(c * Float64(-0.5 / b)) end
function tmp = code(a, b, c) tmp = c * (-0.5 / b); end
code[a_, b_, c_] := N[(c * N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{-0.5}{b}
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
*-commutative33.0%
associate-/r*33.0%
associate-*l/33.0%
Simplified33.0%
Taylor expanded in b around inf 90.9%
+-commutative90.9%
fma-def90.9%
associate-/l*90.9%
unpow290.9%
associate-*r/90.9%
Simplified90.9%
Taylor expanded in c around 0 80.6%
associate-*r/80.6%
associate-*l/80.4%
*-commutative80.4%
Simplified80.4%
Final simplification80.4%
(FPCore (a b c) :precision binary64 (/ -0.5 (/ b c)))
double code(double a, double b, double c) {
return -0.5 / (b / c);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (-0.5d0) / (b / c)
end function
public static double code(double a, double b, double c) {
return -0.5 / (b / c);
}
def code(a, b, c): return -0.5 / (b / c)
function code(a, b, c) return Float64(-0.5 / Float64(b / c)) end
function tmp = code(a, b, c) tmp = -0.5 / (b / c); end
code[a_, b_, c_] := N[(-0.5 / N[(b / c), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-0.5}{\frac{b}{c}}
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/l*33.0%
associate-*r/33.0%
*-commutative33.0%
associate-*l/33.0%
associate-*r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
neg-mul-133.0%
distribute-rgt-neg-in33.0%
times-frac33.0%
metadata-eval33.0%
neg-mul-133.0%
Simplified33.0%
Taylor expanded in b around inf 80.3%
associate-*r/80.2%
Simplified80.2%
pow180.2%
associate-/l*80.2%
Applied egg-rr80.2%
unpow180.2%
associate-*r/80.4%
metadata-eval80.4%
Simplified80.4%
Final simplification80.4%
(FPCore (a b c) :precision binary64 (/ (* c -0.5) b))
double code(double a, double b, double c) {
return (c * -0.5) / b;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (c * (-0.5d0)) / b
end function
public static double code(double a, double b, double c) {
return (c * -0.5) / b;
}
def code(a, b, c): return (c * -0.5) / b
function code(a, b, c) return Float64(Float64(c * -0.5) / b) end
function tmp = code(a, b, c) tmp = (c * -0.5) / b; end
code[a_, b_, c_] := N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot -0.5}{b}
\end{array}
Initial program 33.0%
/-rgt-identity33.0%
metadata-eval33.0%
associate-/r/33.0%
metadata-eval33.0%
metadata-eval33.0%
times-frac33.0%
*-commutative33.0%
times-frac33.0%
*-commutative33.0%
associate-/r*33.0%
associate-*l/33.0%
Simplified33.0%
Taylor expanded in b around inf 80.6%
associate-*r/80.6%
Simplified80.6%
Final simplification80.6%
herbie shell --seed 2023199
(FPCore (a b c)
:name "Cubic critical, medium range"
:precision binary64
:pre (and (and (and (< 1.1102230246251565e-16 a) (< a 9007199254740992.0)) (and (< 1.1102230246251565e-16 b) (< b 9007199254740992.0))) (and (< 1.1102230246251565e-16 c) (< c 9007199254740992.0)))
(/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))