
(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 5 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
(+
(* -0.5625 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0)))
(+
(* -0.5 (/ c b))
(+
(* -0.375 (* (/ (/ c b) (/ b c)) (/ a b)))
(*
-0.16666666666666666
(/
(+ (* 5.0625 (* (pow a 4.0) (pow c 4.0))) (* (pow (* a c) 4.0) 1.265625))
(* a (pow b 7.0))))))))
double code(double a, double b, double c) {
return (-0.5625 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * (((c / b) / (b / c)) * (a / b))) + (-0.16666666666666666 * (((5.0625 * (pow(a, 4.0) * pow(c, 4.0))) + (pow((a * c), 4.0) * 1.265625)) / (a * pow(b, 7.0))))));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = ((-0.5625d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + (((-0.5d0) * (c / b)) + (((-0.375d0) * (((c / b) / (b / c)) * (a / b))) + ((-0.16666666666666666d0) * (((5.0625d0 * ((a ** 4.0d0) * (c ** 4.0d0))) + (((a * c) ** 4.0d0) * 1.265625d0)) / (a * (b ** 7.0d0))))))
end function
public static double code(double a, double b, double c) {
return (-0.5625 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * (((c / b) / (b / c)) * (a / b))) + (-0.16666666666666666 * (((5.0625 * (Math.pow(a, 4.0) * Math.pow(c, 4.0))) + (Math.pow((a * c), 4.0) * 1.265625)) / (a * Math.pow(b, 7.0))))));
}
def code(a, b, c): return (-0.5625 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * (((c / b) / (b / c)) * (a / b))) + (-0.16666666666666666 * (((5.0625 * (math.pow(a, 4.0) * math.pow(c, 4.0))) + (math.pow((a * c), 4.0) * 1.265625)) / (a * math.pow(b, 7.0))))))
function code(a, b, c) return Float64(Float64(-0.5625 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(-0.5 * Float64(c / b)) + Float64(Float64(-0.375 * Float64(Float64(Float64(c / b) / Float64(b / c)) * Float64(a / b))) + Float64(-0.16666666666666666 * Float64(Float64(Float64(5.0625 * Float64((a ^ 4.0) * (c ^ 4.0))) + Float64((Float64(a * c) ^ 4.0) * 1.265625)) / Float64(a * (b ^ 7.0))))))) end
function tmp = code(a, b, c) tmp = (-0.5625 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * (((c / b) / (b / c)) * (a / b))) + (-0.16666666666666666 * (((5.0625 * ((a ^ 4.0) * (c ^ 4.0))) + (((a * c) ^ 4.0) * 1.265625)) / (a * (b ^ 7.0)))))); end
code[a_, b_, c_] := N[(N[(-0.5625 * N[(N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.375 * N[(N[(N[(c / b), $MachinePrecision] / N[(b / c), $MachinePrecision]), $MachinePrecision] * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.16666666666666666 * N[(N[(N[(5.0625 * N[(N[Power[a, 4.0], $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] * 1.265625), $MachinePrecision]), $MachinePrecision] / N[(a * N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \left(\frac{\frac{c}{b}}{\frac{b}{c}} \cdot \frac{a}{b}\right) + -0.16666666666666666 \cdot \frac{5.0625 \cdot \left({a}^{4} \cdot {c}^{4}\right) + {\left(a \cdot c\right)}^{4} \cdot 1.265625}{a \cdot {b}^{7}}\right)\right)
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 97.4%
unpow297.4%
*-commutative97.4%
*-commutative97.4%
swap-sqr97.4%
pow-prod-down97.4%
pow-prod-down97.4%
pow-prod-up97.4%
metadata-eval97.4%
metadata-eval97.4%
Applied egg-rr97.4%
*-commutative97.4%
unpow397.4%
times-frac97.4%
unpow297.4%
frac-times97.4%
pow297.4%
Applied egg-rr97.4%
unpow297.4%
clear-num97.4%
un-div-inv97.4%
Applied egg-rr97.4%
Final simplification97.4%
(FPCore (a b c) :precision binary64 (+ (* -0.5625 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0))) (+ (* -0.5 (/ c b)) (* -0.375 (* (/ (/ c b) (/ b c)) (/ a b))))))
double code(double a, double b, double c) {
return (-0.5625 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b))));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = ((-0.5625d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + (((-0.5d0) * (c / b)) + ((-0.375d0) * (((c / b) / (b / c)) * (a / b))))
end function
public static double code(double a, double b, double c) {
return (-0.5625 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b))));
}
def code(a, b, c): return (-0.5625 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b))))
function code(a, b, c) return Float64(Float64(-0.5625 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(Float64(c / b) / Float64(b / c)) * Float64(a / b))))) end
function tmp = code(a, b, c) tmp = (-0.5625 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + ((-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b)))); end
code[a_, b_, c_] := N[(N[(-0.5625 * N[(N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(N[(c / b), $MachinePrecision] / N[(b / c), $MachinePrecision]), $MachinePrecision] * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + -0.375 \cdot \left(\frac{\frac{c}{b}}{\frac{b}{c}} \cdot \frac{a}{b}\right)\right)
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 96.8%
*-commutative97.4%
unpow397.4%
times-frac97.4%
unpow297.4%
frac-times97.4%
pow297.4%
Applied egg-rr96.8%
unpow297.4%
clear-num97.4%
un-div-inv97.4%
Applied egg-rr96.8%
Final simplification96.8%
(FPCore (a b c) :precision binary64 (+ (* -0.5 (/ c b)) (* -0.375 (* (/ (/ c b) (/ b c)) (/ a b)))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b)));
}
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) * (c / b)) + ((-0.375d0) * (((c / b) / (b / c)) * (a / b)))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b)));
}
def code(a, b, c): return (-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b)))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(Float64(c / b) / Float64(b / c)) * Float64(a / b)))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (-0.375 * (((c / b) / (b / c)) * (a / b))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(N[(c / b), $MachinePrecision] / N[(b / c), $MachinePrecision]), $MachinePrecision] * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + -0.375 \cdot \left(\frac{\frac{c}{b}}{\frac{b}{c}} \cdot \frac{a}{b}\right)
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 95.2%
*-commutative97.4%
unpow397.4%
times-frac97.4%
unpow297.4%
frac-times97.4%
pow297.4%
Applied egg-rr95.2%
unpow297.4%
clear-num97.4%
un-div-inv97.4%
Applied egg-rr95.2%
Final simplification95.2%
(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 18.4%
Taylor expanded in b around inf 89.7%
associate-*r/89.7%
associate-/l*89.4%
Simplified89.4%
associate-/r/89.4%
Applied egg-rr89.4%
Final simplification89.4%
(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 18.4%
Taylor expanded in b around inf 89.7%
associate-*r/89.7%
Simplified89.7%
Final simplification89.7%
herbie shell --seed 2024031
(FPCore (a b c)
:name "Cubic critical, wide range"
:precision binary64
:pre (and (and (and (< 4.930380657631324e-32 a) (< a 2.028240960365167e+31)) (and (< 4.930380657631324e-32 b) (< b 2.028240960365167e+31))) (and (< 4.930380657631324e-32 c) (< c 2.028240960365167e+31)))
(/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))