
(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 5 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
(-
(-
(fma
-0.25
(/ (/ (pow c 4.0) (/ (pow b 6.0) 20.0)) (/ b (pow a 3.0)))
(/ (* (* -2.0 (* a a)) (pow c 3.0)) (pow b 5.0)))
(/ c b))
(/ (* c c) (/ (pow b 3.0) a))))
double code(double a, double b, double c) {
return (fma(-0.25, ((pow(c, 4.0) / (pow(b, 6.0) / 20.0)) / (b / pow(a, 3.0))), (((-2.0 * (a * a)) * pow(c, 3.0)) / pow(b, 5.0))) - (c / b)) - ((c * c) / (pow(b, 3.0) / a));
}
function code(a, b, c) return Float64(Float64(fma(-0.25, Float64(Float64((c ^ 4.0) / Float64((b ^ 6.0) / 20.0)) / Float64(b / (a ^ 3.0))), Float64(Float64(Float64(-2.0 * Float64(a * a)) * (c ^ 3.0)) / (b ^ 5.0))) - Float64(c / b)) - Float64(Float64(c * c) / Float64((b ^ 3.0) / a))) end
code[a_, b_, c_] := N[(N[(N[(-0.25 * N[(N[(N[Power[c, 4.0], $MachinePrecision] / N[(N[Power[b, 6.0], $MachinePrecision] / 20.0), $MachinePrecision]), $MachinePrecision] / N[(b / N[Power[a, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(-2.0 * N[(a * a), $MachinePrecision]), $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(c * c), $MachinePrecision] / N[(N[Power[b, 3.0], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(-0.25, \frac{\frac{{c}^{4}}{\frac{{b}^{6}}{20}}}{\frac{b}{{a}^{3}}}, \frac{\left(-2 \cdot \left(a \cdot a\right)\right) \cdot {c}^{3}}{{b}^{5}}\right) - \frac{c}{b}\right) - \frac{c \cdot c}{\frac{{b}^{3}}{a}}
\end{array}
Initial program 19.0%
neg-sub019.0%
associate-+l-19.0%
sub0-neg19.0%
neg-mul-119.0%
associate-*l/19.0%
*-commutative19.0%
associate-/r*19.0%
/-rgt-identity19.0%
metadata-eval19.0%
Simplified19.1%
Taylor expanded in a around 0 97.6%
Simplified97.6%
Taylor expanded in c around 0 97.6%
*-commutative97.6%
associate-*l/97.6%
associate-/l*97.6%
Simplified97.6%
Final simplification97.6%
(FPCore (a b c) :precision binary64 (- (- (/ (* (* -2.0 (* a a)) (pow c 3.0)) (pow b 5.0)) (/ c b)) (/ (* c c) (/ (pow b 3.0) a))))
double code(double a, double b, double c) {
return ((((-2.0 * (a * a)) * pow(c, 3.0)) / pow(b, 5.0)) - (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 = (((((-2.0d0) * (a * a)) * (c ** 3.0d0)) / (b ** 5.0d0)) - (c / b)) - ((c * c) / ((b ** 3.0d0) / a))
end function
public static double code(double a, double b, double c) {
return ((((-2.0 * (a * a)) * Math.pow(c, 3.0)) / Math.pow(b, 5.0)) - (c / b)) - ((c * c) / (Math.pow(b, 3.0) / a));
}
def code(a, b, c): return ((((-2.0 * (a * a)) * math.pow(c, 3.0)) / math.pow(b, 5.0)) - (c / b)) - ((c * c) / (math.pow(b, 3.0) / a))
function code(a, b, c) return Float64(Float64(Float64(Float64(Float64(-2.0 * Float64(a * a)) * (c ^ 3.0)) / (b ^ 5.0)) - Float64(c / b)) - Float64(Float64(c * c) / Float64((b ^ 3.0) / a))) end
function tmp = code(a, b, c) tmp = ((((-2.0 * (a * a)) * (c ^ 3.0)) / (b ^ 5.0)) - (c / b)) - ((c * c) / ((b ^ 3.0) / a)); end
code[a_, b_, c_] := N[(N[(N[(N[(N[(-2.0 * N[(a * a), $MachinePrecision]), $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(c * c), $MachinePrecision] / N[(N[Power[b, 3.0], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{\left(-2 \cdot \left(a \cdot a\right)\right) \cdot {c}^{3}}{{b}^{5}} - \frac{c}{b}\right) - \frac{c \cdot c}{\frac{{b}^{3}}{a}}
\end{array}
Initial program 19.0%
neg-sub019.0%
associate-+l-19.0%
sub0-neg19.0%
neg-mul-119.0%
associate-*l/19.0%
*-commutative19.0%
associate-/r*19.0%
/-rgt-identity19.0%
metadata-eval19.0%
Simplified19.1%
Taylor expanded in b around inf 96.8%
+-commutative96.8%
mul-1-neg96.8%
unsub-neg96.8%
+-commutative96.8%
mul-1-neg96.8%
unsub-neg96.8%
associate-*r/96.8%
*-commutative96.8%
associate-*r*96.8%
unpow296.8%
associate-/l*96.8%
unpow296.8%
Simplified96.8%
Final simplification96.8%
(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}
\\
\frac{-c}{b} - \frac{c \cdot c}{\frac{{b}^{3}}{a}}
\end{array}
Initial program 19.0%
neg-sub019.0%
associate-+l-19.0%
sub0-neg19.0%
neg-mul-119.0%
associate-*l/19.0%
*-commutative19.0%
associate-/r*19.0%
/-rgt-identity19.0%
metadata-eval19.0%
Simplified19.1%
Taylor expanded in b around inf 94.9%
+-commutative94.9%
mul-1-neg94.9%
unsub-neg94.9%
associate-*r/94.9%
neg-mul-194.9%
associate-/l*94.9%
unpow294.9%
Simplified94.9%
Final simplification94.9%
(FPCore (a b c) :precision binary64 (* (/ (* c (* 4.0 a)) (+ b (+ b (* -2.0 (* a (/ c b)))))) (/ -0.5 a)))
double code(double a, double b, double c) {
return ((c * (4.0 * a)) / (b + (b + (-2.0 * (a * (c / b)))))) * (-0.5 / 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 * (4.0d0 * a)) / (b + (b + ((-2.0d0) * (a * (c / b)))))) * ((-0.5d0) / a)
end function
public static double code(double a, double b, double c) {
return ((c * (4.0 * a)) / (b + (b + (-2.0 * (a * (c / b)))))) * (-0.5 / a);
}
def code(a, b, c): return ((c * (4.0 * a)) / (b + (b + (-2.0 * (a * (c / b)))))) * (-0.5 / a)
function code(a, b, c) return Float64(Float64(Float64(c * Float64(4.0 * a)) / Float64(b + Float64(b + Float64(-2.0 * Float64(a * Float64(c / b)))))) * Float64(-0.5 / a)) end
function tmp = code(a, b, c) tmp = ((c * (4.0 * a)) / (b + (b + (-2.0 * (a * (c / b)))))) * (-0.5 / a); end
code[a_, b_, c_] := N[(N[(N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision] / N[(b + N[(b + N[(-2.0 * N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-0.5 / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot \left(4 \cdot a\right)}{b + \left(b + -2 \cdot \left(a \cdot \frac{c}{b}\right)\right)} \cdot \frac{-0.5}{a}
\end{array}
Initial program 19.0%
neg-sub019.0%
associate-+l-19.0%
sub0-neg19.0%
neg-mul-119.0%
associate-*l/19.0%
*-commutative19.0%
associate-/r*19.0%
/-rgt-identity19.0%
metadata-eval19.0%
Simplified19.1%
Taylor expanded in a around 0 13.4%
*-commutative13.4%
associate-/l*13.4%
Simplified13.4%
flip--13.4%
associate-/l*13.4%
*-commutative13.4%
associate-/l*13.4%
associate-/r/13.4%
associate-/l*13.4%
*-commutative13.4%
associate-/l*13.4%
associate-/r/13.4%
associate-/l*13.4%
*-commutative13.4%
associate-/l*13.4%
associate-/r/13.4%
Applied egg-rr13.4%
Taylor expanded in b around inf 94.6%
*-commutative94.6%
associate-*l*94.6%
Simplified94.6%
Final simplification94.6%
(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 19.0%
neg-sub019.0%
associate-+l-19.0%
sub0-neg19.0%
neg-mul-119.0%
associate-*l/19.0%
*-commutative19.0%
associate-/r*19.0%
/-rgt-identity19.0%
metadata-eval19.0%
Simplified19.1%
Taylor expanded in b around inf 89.6%
associate-*r/89.6%
neg-mul-189.6%
Simplified89.6%
Final simplification89.6%
herbie shell --seed 2023215
(FPCore (a b c)
:name "Quadratic roots, 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) (* (* 4.0 a) c)))) (* 2.0 a)))