
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * 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) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * 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) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}
(FPCore (a b c) :precision binary64 (let* ((t_0 (* c (* a -4.0)))) (/ (* t_0 (/ 0.5 a)) (+ b (sqrt (fma b b t_0))))))
double code(double a, double b, double c) {
double t_0 = c * (a * -4.0);
return (t_0 * (0.5 / a)) / (b + sqrt(fma(b, b, t_0)));
}
function code(a, b, c) t_0 = Float64(c * Float64(a * -4.0)) return Float64(Float64(t_0 * Float64(0.5 / a)) / Float64(b + sqrt(fma(b, b, t_0)))) end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$0 * N[(0.5 / a), $MachinePrecision]), $MachinePrecision] / N[(b + N[Sqrt[N[(b * b + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := c \cdot \left(a \cdot -4\right)\\
\frac{t_0 \cdot \frac{0.5}{a}}{b + \sqrt{\mathsf{fma}\left(b, b, t_0\right)}}
\end{array}
\end{array}
Initial program 30.4%
*-commutative30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
Simplified30.4%
fma-udef30.4%
*-commutative30.4%
metadata-eval30.4%
cancel-sign-sub-inv30.4%
associate-*l*30.4%
*-un-lft-identity30.4%
prod-diff30.4%
Applied egg-rr30.4%
+-commutative30.4%
fma-udef30.4%
*-rgt-identity30.4%
*-rgt-identity30.4%
count-230.4%
*-commutative30.4%
*-commutative30.4%
associate-*r*30.4%
*-rgt-identity30.4%
fma-neg30.3%
*-commutative30.3%
*-commutative30.3%
associate-*r*30.3%
Simplified30.3%
flip--30.3%
add-sqr-sqrt30.8%
associate-*r*30.8%
metadata-eval30.8%
*-commutative30.8%
associate-*r*30.8%
Applied egg-rr30.8%
Simplified99.4%
div-inv99.3%
fma-def99.3%
mul0-lft99.3%
Applied egg-rr99.3%
associate-*l/99.4%
fma-udef99.4%
+-rgt-identity99.4%
*-commutative99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (- (- (/ c b)) (/ (* c c) (/ (pow b 3.0) a))))
double code(double a, double b, double c) {
return -(c / b) - ((c * c) / (pow(b, 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 = -(c / b) - ((c * c) / ((b ** 3.0d0) / a))
end function
public static double code(double a, double b, double c) {
return -(c / b) - ((c * c) / (Math.pow(b, 3.0) / a));
}
def code(a, b, c): return -(c / b) - ((c * c) / (math.pow(b, 3.0) / a))
function code(a, b, c) return Float64(Float64(-Float64(c / b)) - Float64(Float64(c * c) / Float64((b ^ 3.0) / a))) end
function tmp = code(a, b, c) tmp = -(c / b) - ((c * c) / ((b ^ 3.0) / a)); end
code[a_, b_, c_] := N[((-N[(c / b), $MachinePrecision]) - N[(N[(c * c), $MachinePrecision] / N[(N[Power[b, 3.0], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(-\frac{c}{b}\right) - \frac{c \cdot c}{\frac{{b}^{3}}{a}}
\end{array}
Initial program 30.4%
/-rgt-identity30.4%
metadata-eval30.4%
associate-/l*30.4%
associate-*r/30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
associate-/r*30.4%
metadata-eval30.4%
metadata-eval30.4%
Simplified30.4%
Taylor expanded in b around inf 92.5%
+-commutative92.5%
mul-1-neg92.5%
unsub-neg92.5%
mul-1-neg92.5%
distribute-neg-frac92.5%
associate-/l*92.5%
unpow292.5%
Simplified92.5%
Final simplification92.5%
(FPCore (a b c) :precision binary64 (/ (/ (+ (* c (* a -4.0)) (* 0.0 (* b b))) (+ b (+ b (* -2.0 (/ (* c a) b))))) (* a 2.0)))
double code(double a, double b, double c) {
return (((c * (a * -4.0)) + (0.0 * (b * b))) / (b + (b + (-2.0 * ((c * a) / b))))) / (a * 2.0);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (((c * (a * (-4.0d0))) + (0.0d0 * (b * b))) / (b + (b + ((-2.0d0) * ((c * a) / b))))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return (((c * (a * -4.0)) + (0.0 * (b * b))) / (b + (b + (-2.0 * ((c * a) / b))))) / (a * 2.0);
}
def code(a, b, c): return (((c * (a * -4.0)) + (0.0 * (b * b))) / (b + (b + (-2.0 * ((c * a) / b))))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(Float64(c * Float64(a * -4.0)) + Float64(0.0 * Float64(b * b))) / Float64(b + Float64(b + Float64(-2.0 * Float64(Float64(c * a) / b))))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = (((c * (a * -4.0)) + (0.0 * (b * b))) / (b + (b + (-2.0 * ((c * a) / b))))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision] + N[(0.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b + N[(b + N[(-2.0 * N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot -4\right) + 0 \cdot \left(b \cdot b\right)}{b + \left(b + -2 \cdot \frac{c \cdot a}{b}\right)}}{a \cdot 2}
\end{array}
Initial program 30.4%
*-commutative30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
Simplified30.4%
fma-udef30.4%
*-commutative30.4%
metadata-eval30.4%
cancel-sign-sub-inv30.4%
associate-*l*30.4%
*-un-lft-identity30.4%
prod-diff30.4%
Applied egg-rr30.4%
+-commutative30.4%
fma-udef30.4%
*-rgt-identity30.4%
*-rgt-identity30.4%
count-230.4%
*-commutative30.4%
*-commutative30.4%
associate-*r*30.4%
*-rgt-identity30.4%
fma-neg30.3%
*-commutative30.3%
*-commutative30.3%
associate-*r*30.3%
Simplified30.3%
flip--30.3%
add-sqr-sqrt30.8%
associate-*r*30.8%
metadata-eval30.8%
*-commutative30.8%
associate-*r*30.8%
Applied egg-rr30.8%
Simplified99.4%
Taylor expanded in b around inf 92.4%
Final simplification92.4%
(FPCore (a b c) :precision binary64 (/ (/ (+ (* c (* a -4.0)) (* 0.0 (* b b))) (+ (* -2.0 (/ (* c a) b)) (* b 2.0))) (* a 2.0)))
double code(double a, double b, double c) {
return (((c * (a * -4.0)) + (0.0 * (b * b))) / ((-2.0 * ((c * a) / b)) + (b * 2.0))) / (a * 2.0);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (((c * (a * (-4.0d0))) + (0.0d0 * (b * b))) / (((-2.0d0) * ((c * a) / b)) + (b * 2.0d0))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return (((c * (a * -4.0)) + (0.0 * (b * b))) / ((-2.0 * ((c * a) / b)) + (b * 2.0))) / (a * 2.0);
}
def code(a, b, c): return (((c * (a * -4.0)) + (0.0 * (b * b))) / ((-2.0 * ((c * a) / b)) + (b * 2.0))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(Float64(c * Float64(a * -4.0)) + Float64(0.0 * Float64(b * b))) / Float64(Float64(-2.0 * Float64(Float64(c * a) / b)) + Float64(b * 2.0))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = (((c * (a * -4.0)) + (0.0 * (b * b))) / ((-2.0 * ((c * a) / b)) + (b * 2.0))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision] + N[(0.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(-2.0 * N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision] + N[(b * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot -4\right) + 0 \cdot \left(b \cdot b\right)}{-2 \cdot \frac{c \cdot a}{b} + b \cdot 2}}{a \cdot 2}
\end{array}
Initial program 30.4%
*-commutative30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
Simplified30.4%
fma-udef30.4%
*-commutative30.4%
metadata-eval30.4%
cancel-sign-sub-inv30.4%
associate-*l*30.4%
*-un-lft-identity30.4%
prod-diff30.4%
Applied egg-rr30.4%
+-commutative30.4%
fma-udef30.4%
*-rgt-identity30.4%
*-rgt-identity30.4%
count-230.4%
*-commutative30.4%
*-commutative30.4%
associate-*r*30.4%
*-rgt-identity30.4%
fma-neg30.3%
*-commutative30.3%
*-commutative30.3%
associate-*r*30.3%
Simplified30.3%
flip--30.3%
add-sqr-sqrt30.8%
associate-*r*30.8%
metadata-eval30.8%
*-commutative30.8%
associate-*r*30.8%
Applied egg-rr30.8%
Simplified99.4%
Taylor expanded in b around inf 92.4%
Final simplification92.4%
(FPCore (a b c) :precision binary64 (* (/ 0.5 a) (/ (* c (* a -4.0)) (+ b (+ b (/ -2.0 (/ b (* c a))))))))
double code(double a, double b, double c) {
return (0.5 / a) * ((c * (a * -4.0)) / (b + (b + (-2.0 / (b / (c * a))))));
}
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 / a) * ((c * (a * (-4.0d0))) / (b + (b + ((-2.0d0) / (b / (c * a))))))
end function
public static double code(double a, double b, double c) {
return (0.5 / a) * ((c * (a * -4.0)) / (b + (b + (-2.0 / (b / (c * a))))));
}
def code(a, b, c): return (0.5 / a) * ((c * (a * -4.0)) / (b + (b + (-2.0 / (b / (c * a))))))
function code(a, b, c) return Float64(Float64(0.5 / a) * Float64(Float64(c * Float64(a * -4.0)) / Float64(b + Float64(b + Float64(-2.0 / Float64(b / Float64(c * a))))))) end
function tmp = code(a, b, c) tmp = (0.5 / a) * ((c * (a * -4.0)) / (b + (b + (-2.0 / (b / (c * a)))))); end
code[a_, b_, c_] := N[(N[(0.5 / a), $MachinePrecision] * N[(N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision] / N[(b + N[(b + N[(-2.0 / N[(b / N[(c * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.5}{a} \cdot \frac{c \cdot \left(a \cdot -4\right)}{b + \left(b + \frac{-2}{\frac{b}{c \cdot a}}\right)}
\end{array}
Initial program 30.4%
/-rgt-identity30.4%
metadata-eval30.4%
associate-/l*30.4%
associate-*r/30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
associate-/r*30.4%
metadata-eval30.4%
metadata-eval30.4%
Simplified30.4%
Taylor expanded in b around inf 22.1%
associate-*r/22.1%
Simplified22.1%
flip--22.1%
associate-/l*22.1%
associate-/l*22.1%
associate-/l*22.1%
Applied egg-rr22.1%
Taylor expanded in b around inf 92.3%
*-commutative92.3%
*-commutative92.3%
*-commutative92.3%
associate-*l*92.3%
Simplified92.3%
Final simplification92.3%
(FPCore (a b c) :precision binary64 (- (/ c b)))
double code(double a, double b, double c) {
return -(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 = -(c / b)
end function
public static double code(double a, double b, double c) {
return -(c / b);
}
def code(a, b, c): return -(c / b)
function code(a, b, c) return Float64(-Float64(c / b)) end
function tmp = code(a, b, c) tmp = -(c / b); end
code[a_, b_, c_] := (-N[(c / b), $MachinePrecision])
\begin{array}{l}
\\
-\frac{c}{b}
\end{array}
Initial program 30.4%
/-rgt-identity30.4%
metadata-eval30.4%
associate-/l*30.4%
associate-*r/30.4%
+-commutative30.4%
unsub-neg30.4%
fma-neg30.4%
associate-*l*30.4%
*-commutative30.4%
distribute-rgt-neg-in30.4%
metadata-eval30.4%
associate-/r*30.4%
metadata-eval30.4%
metadata-eval30.4%
Simplified30.4%
Taylor expanded in b around inf 82.7%
mul-1-neg82.7%
distribute-neg-frac82.7%
Simplified82.7%
Final simplification82.7%
herbie shell --seed 2023207
(FPCore (a b c)
:name "Quadratic roots, 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) (* (* 4.0 a) c)))) (* 2.0 a)))