
(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
-2.0
(* (/ (pow c 3.0) (pow b 5.0)) (* a a))
(/ (/ (* (* -5.0 (pow a 3.0)) (pow c 4.0)) (pow b 6.0)) b))
(/ c b))
(* a (/ c (/ (pow b 3.0) c)))))
double code(double a, double b, double c) {
return (fma(-2.0, ((pow(c, 3.0) / pow(b, 5.0)) * (a * a)), ((((-5.0 * pow(a, 3.0)) * pow(c, 4.0)) / pow(b, 6.0)) / b)) - (c / b)) - (a * (c / (pow(b, 3.0) / c)));
}
function code(a, b, c) return Float64(Float64(fma(-2.0, Float64(Float64((c ^ 3.0) / (b ^ 5.0)) * Float64(a * a)), Float64(Float64(Float64(Float64(-5.0 * (a ^ 3.0)) * (c ^ 4.0)) / (b ^ 6.0)) / b)) - Float64(c / b)) - Float64(a * Float64(c / Float64((b ^ 3.0) / c)))) end
code[a_, b_, c_] := N[(N[(N[(-2.0 * N[(N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(-5.0 * N[Power[a, 3.0], $MachinePrecision]), $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(a * N[(c / N[(N[Power[b, 3.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(-2, \frac{{c}^{3}}{{b}^{5}} \cdot \left(a \cdot a\right), \frac{\frac{\left(-5 \cdot {a}^{3}\right) \cdot {c}^{4}}{{b}^{6}}}{b}\right) - \frac{c}{b}\right) - a \cdot \frac{c}{\frac{{b}^{3}}{c}}
\end{array}
Initial program 18.4%
Taylor expanded in a around 0 97.4%
Simplified97.4%
Taylor expanded in c around 0 97.4%
associate-*r/97.4%
*-commutative97.4%
associate-*r*97.4%
Simplified97.4%
Final simplification97.4%
(FPCore (a b c) :precision binary64 (- (- (/ (* -2.0 (* a (* (pow c 3.0) a))) (pow b 5.0)) (/ c b)) (* a (/ c (/ (pow b 3.0) c)))))
double code(double a, double b, double c) {
return (((-2.0 * (a * (pow(c, 3.0) * a))) / pow(b, 5.0)) - (c / b)) - (a * (c / (pow(b, 3.0) / c)));
}
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 * ((c ** 3.0d0) * a))) / (b ** 5.0d0)) - (c / b)) - (a * (c / ((b ** 3.0d0) / c)))
end function
public static double code(double a, double b, double c) {
return (((-2.0 * (a * (Math.pow(c, 3.0) * a))) / Math.pow(b, 5.0)) - (c / b)) - (a * (c / (Math.pow(b, 3.0) / c)));
}
def code(a, b, c): return (((-2.0 * (a * (math.pow(c, 3.0) * a))) / math.pow(b, 5.0)) - (c / b)) - (a * (c / (math.pow(b, 3.0) / c)))
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * Float64(a * Float64((c ^ 3.0) * a))) / (b ^ 5.0)) - Float64(c / b)) - Float64(a * Float64(c / Float64((b ^ 3.0) / c)))) end
function tmp = code(a, b, c) tmp = (((-2.0 * (a * ((c ^ 3.0) * a))) / (b ^ 5.0)) - (c / b)) - (a * (c / ((b ^ 3.0) / c))); end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[(a * N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(a * N[(c / N[(N[Power[b, 3.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2 \cdot \left(a \cdot \left({c}^{3} \cdot a\right)\right)}{{b}^{5}} - \frac{c}{b}\right) - a \cdot \frac{c}{\frac{{b}^{3}}{c}}
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 96.4%
+-commutative96.4%
mul-1-neg96.4%
unsub-neg96.4%
+-commutative96.4%
mul-1-neg96.4%
unsub-neg96.4%
associate-*r/96.4%
*-commutative96.4%
unpow296.4%
associate-*l*96.4%
associate-/l*96.4%
associate-/r/96.4%
Simplified96.4%
Final simplification96.4%
(FPCore (a b c) :precision binary64 (- (- (/ c b)) (* a (/ c (/ (pow b 3.0) c)))))
double code(double a, double b, double c) {
return -(c / b) - (a * (c / (pow(b, 3.0) / c)));
}
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) - (a * (c / ((b ** 3.0d0) / c)))
end function
public static double code(double a, double b, double c) {
return -(c / b) - (a * (c / (Math.pow(b, 3.0) / c)));
}
def code(a, b, c): return -(c / b) - (a * (c / (math.pow(b, 3.0) / c)))
function code(a, b, c) return Float64(Float64(-Float64(c / b)) - Float64(a * Float64(c / Float64((b ^ 3.0) / c)))) end
function tmp = code(a, b, c) tmp = -(c / b) - (a * (c / ((b ^ 3.0) / c))); end
code[a_, b_, c_] := N[((-N[(c / b), $MachinePrecision]) - N[(a * N[(c / N[(N[Power[b, 3.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(-\frac{c}{b}\right) - a \cdot \frac{c}{\frac{{b}^{3}}{c}}
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 94.6%
+-commutative94.6%
mul-1-neg94.6%
unsub-neg94.6%
mul-1-neg94.6%
associate-/l*94.6%
associate-/r/94.6%
unpow294.6%
associate-/l*94.6%
Simplified94.6%
Final simplification94.6%
(FPCore (a b c) :precision binary64 (/ (/ (* c (* a 4.0)) (- (- (- b) b) (* (/ -2.0 b) (* c a)))) (* a 2.0)))
double code(double a, double b, double c) {
return ((c * (a * 4.0)) / ((-b - b) - ((-2.0 / b) * (c * a)))) / (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)) / ((-b - b) - (((-2.0d0) / b) * (c * a)))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return ((c * (a * 4.0)) / ((-b - b) - ((-2.0 / b) * (c * a)))) / (a * 2.0);
}
def code(a, b, c): return ((c * (a * 4.0)) / ((-b - b) - ((-2.0 / b) * (c * a)))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(c * Float64(a * 4.0)) / Float64(Float64(Float64(-b) - b) - Float64(Float64(-2.0 / b) * Float64(c * a)))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = ((c * (a * 4.0)) / ((-b - b) - ((-2.0 / b) * (c * a)))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision] / N[(N[((-b) - b), $MachinePrecision] - N[(N[(-2.0 / b), $MachinePrecision] * N[(c * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot 4\right)}{\left(\left(-b\right) - b\right) - \frac{-2}{b} \cdot \left(c \cdot a\right)}}{a \cdot 2}
\end{array}
Initial program 18.4%
Taylor expanded in b around inf 12.6%
associate-*r/12.6%
Simplified12.6%
flip-+12.7%
associate-/l*12.7%
associate-/l*12.7%
associate-/l*12.7%
Applied egg-rr12.7%
sqr-neg12.7%
associate-/r/12.7%
associate-/r/12.7%
associate--r+12.7%
associate-/r/12.7%
Simplified12.7%
Taylor expanded in b around inf 94.4%
*-commutative94.4%
*-commutative94.4%
*-commutative94.4%
associate-*l*94.4%
Simplified94.4%
Final simplification94.4%
(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 18.4%
Taylor expanded in b around inf 89.8%
mul-1-neg89.8%
Simplified89.8%
Final simplification89.8%
herbie shell --seed 2023273
(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)))