
(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
(let* ((t_0 (pow (* a c) 4.0)))
(+
(* -2.0 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0)))
(-
(-
(* -0.25 (/ (+ (* 16.0 t_0) (* 4.0 t_0)) (* a (pow b 7.0))))
(* (pow (/ c b) 2.0) (/ a b)))
(/ c b)))))
double code(double a, double b, double c) {
double t_0 = pow((a * c), 4.0);
return (-2.0 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + (((-0.25 * (((16.0 * t_0) + (4.0 * t_0)) / (a * pow(b, 7.0)))) - (pow((c / b), 2.0) * (a / b))) - (c / b));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8) :: t_0
t_0 = (a * c) ** 4.0d0
code = ((-2.0d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + ((((-0.25d0) * (((16.0d0 * t_0) + (4.0d0 * t_0)) / (a * (b ** 7.0d0)))) - (((c / b) ** 2.0d0) * (a / b))) - (c / b))
end function
public static double code(double a, double b, double c) {
double t_0 = Math.pow((a * c), 4.0);
return (-2.0 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + (((-0.25 * (((16.0 * t_0) + (4.0 * t_0)) / (a * Math.pow(b, 7.0)))) - (Math.pow((c / b), 2.0) * (a / b))) - (c / b));
}
def code(a, b, c): t_0 = math.pow((a * c), 4.0) return (-2.0 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + (((-0.25 * (((16.0 * t_0) + (4.0 * t_0)) / (a * math.pow(b, 7.0)))) - (math.pow((c / b), 2.0) * (a / b))) - (c / b))
function code(a, b, c) t_0 = Float64(a * c) ^ 4.0 return Float64(Float64(-2.0 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(Float64(-0.25 * Float64(Float64(Float64(16.0 * t_0) + Float64(4.0 * t_0)) / Float64(a * (b ^ 7.0)))) - Float64((Float64(c / b) ^ 2.0) * Float64(a / b))) - Float64(c / b))) end
function tmp = code(a, b, c) t_0 = (a * c) ^ 4.0; tmp = (-2.0 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + (((-0.25 * (((16.0 * t_0) + (4.0 * t_0)) / (a * (b ^ 7.0)))) - (((c / b) ^ 2.0) * (a / b))) - (c / b)); end
code[a_, b_, c_] := Block[{t$95$0 = N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision]}, N[(N[(-2.0 * 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[(N[(-0.25 * N[(N[(N[(16.0 * t$95$0), $MachinePrecision] + N[(4.0 * t$95$0), $MachinePrecision]), $MachinePrecision] / N[(a * N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision] * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := {\left(a \cdot c\right)}^{4}\\
-2 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(\left(-0.25 \cdot \frac{16 \cdot t_0 + 4 \cdot t_0}{a \cdot {b}^{7}} - {\left(\frac{c}{b}\right)}^{2} \cdot \frac{a}{b}\right) - \frac{c}{b}\right)
\end{array}
\end{array}
Initial program 18.4%
*-commutative18.4%
Simplified18.4%
Taylor expanded in b around inf 98.1%
unpow298.1%
*-commutative98.1%
*-commutative98.1%
swap-sqr98.1%
pow-prod-down98.1%
pow-prod-down98.1%
pow-sqr98.1%
metadata-eval98.1%
metadata-eval98.1%
Applied egg-rr98.1%
pow-prod-down98.1%
metadata-eval98.1%
pow-sqr98.1%
pow-prod-down98.1%
pow198.1%
metadata-eval98.1%
pow-prod-down98.1%
pow198.1%
metadata-eval98.1%
sqr-pow98.1%
pow-prod-down98.1%
Applied egg-rr98.1%
unpow298.1%
pow-sqr98.1%
metadata-eval98.1%
Simplified98.1%
*-commutative98.1%
unpow398.1%
times-frac98.1%
unpow298.1%
frac-times98.1%
pow198.1%
metadata-eval98.1%
pow198.1%
metadata-eval98.1%
pow-sqr98.1%
metadata-eval98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (a b c) :precision binary64 (- (* -2.0 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0))) (+ (/ c b) (/ (* a (pow c 2.0)) (pow b 3.0)))))
double code(double a, double b, double c) {
return (-2.0 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) - ((c / b) + ((a * pow(c, 2.0)) / pow(b, 3.0)));
}
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 ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) - ((c / b) + ((a * (c ** 2.0d0)) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (-2.0 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) - ((c / b) + ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (-2.0 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) - ((c / b) + ((a * math.pow(c, 2.0)) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(-2.0 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) - Float64(Float64(c / b) + Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (-2.0 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) - ((c / b) + ((a * (c ^ 2.0)) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(-2.0 * 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[(c / b), $MachinePrecision] + N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-2 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} - \left(\frac{c}{b} + \frac{a \cdot {c}^{2}}{{b}^{3}}\right)
\end{array}
Initial program 18.4%
*-commutative18.4%
Simplified18.4%
Taylor expanded in b around inf 97.2%
Final simplification97.2%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* (pow (/ c b) 2.0) (/ a b))))
double code(double a, double b, double c) {
return (-c / b) - (pow((c / b), 2.0) * (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 = (-c / b) - (((c / b) ** 2.0d0) * (a / b))
end function
public static double code(double a, double b, double c) {
return (-c / b) - (Math.pow((c / b), 2.0) * (a / b));
}
def code(a, b, c): return (-c / b) - (math.pow((c / b), 2.0) * (a / b))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64((Float64(c / b) ^ 2.0) * Float64(a / b))) end
function tmp = code(a, b, c) tmp = (-c / b) - (((c / b) ^ 2.0) * (a / b)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision] * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - {\left(\frac{c}{b}\right)}^{2} \cdot \frac{a}{b}
\end{array}
Initial program 18.4%
*-commutative18.4%
Simplified18.4%
Taylor expanded in b around inf 95.5%
distribute-lft-out95.5%
Simplified95.5%
*-commutative98.1%
unpow398.1%
times-frac98.1%
unpow298.1%
frac-times98.1%
pow198.1%
metadata-eval98.1%
pow198.1%
metadata-eval98.1%
pow-sqr98.1%
metadata-eval98.1%
metadata-eval98.1%
Applied egg-rr95.5%
Final simplification95.5%
(FPCore (a b c) :precision binary64 (/ -1.0 (- (/ b c) (/ a b))))
double code(double a, double b, double c) {
return -1.0 / ((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 = (-1.0d0) / ((b / c) - (a / b))
end function
public static double code(double a, double b, double c) {
return -1.0 / ((b / c) - (a / b));
}
def code(a, b, c): return -1.0 / ((b / c) - (a / b))
function code(a, b, c) return Float64(-1.0 / Float64(Float64(b / c) - Float64(a / b))) end
function tmp = code(a, b, c) tmp = -1.0 / ((b / c) - (a / b)); end
code[a_, b_, c_] := N[(-1.0 / N[(N[(b / c), $MachinePrecision] - N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{\frac{b}{c} - \frac{a}{b}}
\end{array}
Initial program 18.4%
*-commutative18.4%
Simplified18.4%
Taylor expanded in b around inf 95.5%
distribute-lft-out95.5%
Simplified95.5%
frac-add95.0%
clear-num94.9%
associate-*r*94.9%
Applied egg-rr94.9%
Taylor expanded in b around inf 95.4%
+-commutative95.4%
mul-1-neg95.4%
unsub-neg95.4%
Simplified95.4%
Final simplification95.4%
(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%
*-commutative18.4%
Simplified18.4%
Taylor expanded in b around inf 90.2%
mul-1-neg90.2%
Simplified90.2%
Final simplification90.2%
herbie shell --seed 2023326
(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)))