
(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 8 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 (let* ((t_0 (+ b (sqrt (fma (* a c) -3.0 (* b b)))))) (/ (/ (- (/ (- (* b b) (* b b)) t_0) (/ (* c (* a -3.0)) t_0)) a) -3.0)))
double code(double a, double b, double c) {
double t_0 = b + sqrt(fma((a * c), -3.0, (b * b)));
return (((((b * b) - (b * b)) / t_0) - ((c * (a * -3.0)) / t_0)) / a) / -3.0;
}
function code(a, b, c) t_0 = Float64(b + sqrt(fma(Float64(a * c), -3.0, Float64(b * b)))) return Float64(Float64(Float64(Float64(Float64(Float64(b * b) - Float64(b * b)) / t_0) - Float64(Float64(c * Float64(a * -3.0)) / t_0)) / a) / -3.0) end
code[a_, b_, c_] := Block[{t$95$0 = N[(b + N[Sqrt[N[(N[(a * c), $MachinePrecision] * -3.0 + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(N[(N[(N[(b * b), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] - N[(N[(c * N[(a * -3.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision] / -3.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := b + \sqrt{\mathsf{fma}\left(a \cdot c, -3, b \cdot b\right)}\\
\frac{\frac{\frac{b \cdot b - b \cdot b}{t\_0} - \frac{c \cdot \left(a \cdot -3\right)}{t\_0}}{a}}{-3}
\end{array}
\end{array}
Initial program 29.0%
Applied egg-rr28.9%
+-commutativeN/A
accelerator-lowering-fma.f64N/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
*-lowering-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
*-lowering-*.f6429.0
Applied egg-rr29.0%
flip--N/A
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
rem-square-sqrtN/A
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
Applied egg-rr99.2%
(FPCore (a b c) :precision binary64 (let* ((t_0 (* a (+ b (sqrt (fma (* a c) -3.0 (* b b))))))) (/ (- (/ (- (* b b) (* b b)) t_0) (/ (* c (* a -3.0)) t_0)) -3.0)))
double code(double a, double b, double c) {
double t_0 = a * (b + sqrt(fma((a * c), -3.0, (b * b))));
return ((((b * b) - (b * b)) / t_0) - ((c * (a * -3.0)) / t_0)) / -3.0;
}
function code(a, b, c) t_0 = Float64(a * Float64(b + sqrt(fma(Float64(a * c), -3.0, Float64(b * b))))) return Float64(Float64(Float64(Float64(Float64(b * b) - Float64(b * b)) / t_0) - Float64(Float64(c * Float64(a * -3.0)) / t_0)) / -3.0) end
code[a_, b_, c_] := Block[{t$95$0 = N[(a * N[(b + N[Sqrt[N[(N[(a * c), $MachinePrecision] * -3.0 + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(N[(N[(b * b), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] - N[(N[(c * N[(a * -3.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / -3.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := a \cdot \left(b + \sqrt{\mathsf{fma}\left(a \cdot c, -3, b \cdot b\right)}\right)\\
\frac{\frac{b \cdot b - b \cdot b}{t\_0} - \frac{c \cdot \left(a \cdot -3\right)}{t\_0}}{-3}
\end{array}
\end{array}
Initial program 29.0%
Applied egg-rr28.9%
+-commutativeN/A
accelerator-lowering-fma.f64N/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
*-lowering-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
*-lowering-*.f6429.0
Applied egg-rr29.0%
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
flip--N/A
associate-/l/N/A
rem-square-sqrtN/A
+-commutativeN/A
associate--r+N/A
div-subN/A
Applied egg-rr99.2%
(FPCore (a b c) :precision binary64 (let* ((t_0 (* a (* -3.0 (+ b (sqrt (fma (* a c) -3.0 (* b b)))))))) (- (/ (- (* b b) (* b b)) t_0) (/ (* c (* a -3.0)) t_0))))
double code(double a, double b, double c) {
double t_0 = a * (-3.0 * (b + sqrt(fma((a * c), -3.0, (b * b)))));
return (((b * b) - (b * b)) / t_0) - ((c * (a * -3.0)) / t_0);
}
function code(a, b, c) t_0 = Float64(a * Float64(-3.0 * Float64(b + sqrt(fma(Float64(a * c), -3.0, Float64(b * b)))))) return Float64(Float64(Float64(Float64(b * b) - Float64(b * b)) / t_0) - Float64(Float64(c * Float64(a * -3.0)) / t_0)) end
code[a_, b_, c_] := Block[{t$95$0 = N[(a * N[(-3.0 * N[(b + N[Sqrt[N[(N[(a * c), $MachinePrecision] * -3.0 + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(N[(b * b), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] - N[(N[(c * N[(a * -3.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := a \cdot \left(-3 \cdot \left(b + \sqrt{\mathsf{fma}\left(a \cdot c, -3, b \cdot b\right)}\right)\right)\\
\frac{b \cdot b - b \cdot b}{t\_0} - \frac{c \cdot \left(a \cdot -3\right)}{t\_0}
\end{array}
\end{array}
Initial program 29.0%
Applied egg-rr28.9%
+-commutativeN/A
accelerator-lowering-fma.f64N/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
distribute-lft-neg-inN/A
*-lowering-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
*-lowering-*.f6429.0
Applied egg-rr29.0%
associate-/r*N/A
Applied egg-rr99.1%
(FPCore (a b c) :precision binary64 (fma a (/ (fma c (* c -0.375) (/ (* a (* -0.5625 (* c (* c c)))) (* b b))) (* b (* b b))) (* -0.5 (/ c b))))
double code(double a, double b, double c) {
return fma(a, (fma(c, (c * -0.375), ((a * (-0.5625 * (c * (c * c)))) / (b * b))) / (b * (b * b))), (-0.5 * (c / b)));
}
function code(a, b, c) return fma(a, Float64(fma(c, Float64(c * -0.375), Float64(Float64(a * Float64(-0.5625 * Float64(c * Float64(c * c)))) / Float64(b * b))) / Float64(b * Float64(b * b))), Float64(-0.5 * Float64(c / b))) end
code[a_, b_, c_] := N[(a * N[(N[(c * N[(c * -0.375), $MachinePrecision] + N[(N[(a * N[(-0.5625 * N[(c * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(a, \frac{\mathsf{fma}\left(c, c \cdot -0.375, \frac{a \cdot \left(-0.5625 \cdot \left(c \cdot \left(c \cdot c\right)\right)\right)}{b \cdot b}\right)}{b \cdot \left(b \cdot b\right)}, -0.5 \cdot \frac{c}{b}\right)
\end{array}
Initial program 29.0%
Taylor expanded in a around 0
Simplified96.1%
Taylor expanded in b around inf
/-lowering-/.f64N/A
Simplified94.8%
(FPCore (a b c)
:precision binary64
(/
(*
c
(fma
c
(fma
-0.375
(/ a (* b b))
(/ (* -0.5625 (* a (* a c))) (* (* b b) (* b b))))
-0.5))
b))
double code(double a, double b, double c) {
return (c * fma(c, fma(-0.375, (a / (b * b)), ((-0.5625 * (a * (a * c))) / ((b * b) * (b * b)))), -0.5)) / b;
}
function code(a, b, c) return Float64(Float64(c * fma(c, fma(-0.375, Float64(a / Float64(b * b)), Float64(Float64(-0.5625 * Float64(a * Float64(a * c))) / Float64(Float64(b * b) * Float64(b * b)))), -0.5)) / b) end
code[a_, b_, c_] := N[(N[(c * N[(c * N[(-0.375 * N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.5625 * N[(a * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(b * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot \mathsf{fma}\left(c, \mathsf{fma}\left(-0.375, \frac{a}{b \cdot b}, \frac{-0.5625 \cdot \left(a \cdot \left(a \cdot c\right)\right)}{\left(b \cdot b\right) \cdot \left(b \cdot b\right)}\right), -0.5\right)}{b}
\end{array}
Initial program 29.0%
Taylor expanded in b around inf
/-lowering-/.f64N/A
Simplified94.8%
Taylor expanded in c around 0
*-lowering-*.f64N/A
sub-negN/A
metadata-evalN/A
accelerator-lowering-fma.f64N/A
Simplified94.7%
(FPCore (a b c) :precision binary64 (/ (fma a (/ (* -0.375 (* c c)) (* b b)) (* c -0.5)) b))
double code(double a, double b, double c) {
return fma(a, ((-0.375 * (c * c)) / (b * b)), (c * -0.5)) / b;
}
function code(a, b, c) return Float64(fma(a, Float64(Float64(-0.375 * Float64(c * c)) / Float64(b * b)), Float64(c * -0.5)) / b) end
code[a_, b_, c_] := N[(N[(a * N[(N[(-0.375 * N[(c * c), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(c * -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(a, \frac{-0.375 \cdot \left(c \cdot c\right)}{b \cdot b}, c \cdot -0.5\right)}{b}
\end{array}
Initial program 29.0%
Taylor expanded in b around inf
/-lowering-/.f64N/A
Simplified91.9%
Final simplification91.9%
(FPCore (a b c) :precision binary64 (/ (* c (fma c (* -0.375 (/ a (* b b))) -0.5)) b))
double code(double a, double b, double c) {
return (c * fma(c, (-0.375 * (a / (b * b))), -0.5)) / b;
}
function code(a, b, c) return Float64(Float64(c * fma(c, Float64(-0.375 * Float64(a / Float64(b * b))), -0.5)) / b) end
code[a_, b_, c_] := N[(N[(c * N[(c * N[(-0.375 * N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot \mathsf{fma}\left(c, -0.375 \cdot \frac{a}{b \cdot b}, -0.5\right)}{b}
\end{array}
Initial program 29.0%
Taylor expanded in b around inf
/-lowering-/.f64N/A
Simplified91.9%
Taylor expanded in c around 0
associate-*r/N/A
associate-*r*N/A
associate-*l/N/A
associate-*r/N/A
sub-negN/A
metadata-evalN/A
*-lowering-*.f64N/A
*-commutativeN/A
accelerator-lowering-fma.f64N/A
*-lowering-*.f64N/A
/-lowering-/.f64N/A
unpow2N/A
*-lowering-*.f6491.8
Simplified91.8%
(FPCore (a b c) :precision binary64 (* -0.5 (/ c b)))
double code(double a, double b, double c) {
return -0.5 * (c / 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)
end function
public static double code(double a, double b, double c) {
return -0.5 * (c / b);
}
def code(a, b, c): return -0.5 * (c / b)
function code(a, b, c) return Float64(-0.5 * Float64(c / b)) end
function tmp = code(a, b, c) tmp = -0.5 * (c / b); end
code[a_, b_, c_] := N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b}
\end{array}
Initial program 29.0%
Taylor expanded in b around inf
*-lowering-*.f64N/A
/-lowering-/.f6483.2
Simplified83.2%
herbie shell --seed 2024199
(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)))