
(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 7 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 c 4.0) (pow b 6.0))))
(fma
-2.0
(* (/ (* a a) (pow b 5.0)) (pow c 3.0))
(-
(-
(/ (* -0.25 (pow a 3.0)) (/ b (fma 16.0 t_0 (* 4.0 t_0))))
(* (/ a (pow b 3.0)) (* c c)))
(/ c b)))))
double code(double a, double b, double c) {
double t_0 = pow(c, 4.0) / pow(b, 6.0);
return fma(-2.0, (((a * a) / pow(b, 5.0)) * pow(c, 3.0)), ((((-0.25 * pow(a, 3.0)) / (b / fma(16.0, t_0, (4.0 * t_0)))) - ((a / pow(b, 3.0)) * (c * c))) - (c / b)));
}
function code(a, b, c) t_0 = Float64((c ^ 4.0) / (b ^ 6.0)) return fma(-2.0, Float64(Float64(Float64(a * a) / (b ^ 5.0)) * (c ^ 3.0)), Float64(Float64(Float64(Float64(-0.25 * (a ^ 3.0)) / Float64(b / fma(16.0, t_0, Float64(4.0 * t_0)))) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))) - Float64(c / b))) end
code[a_, b_, c_] := Block[{t$95$0 = N[(N[Power[c, 4.0], $MachinePrecision] / N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision]}, N[(-2.0 * N[(N[(N[(a * a), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(-0.25 * N[Power[a, 3.0], $MachinePrecision]), $MachinePrecision] / N[(b / N[(16.0 * t$95$0 + N[(4.0 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{{c}^{4}}{{b}^{6}}\\
\mathsf{fma}\left(-2, \frac{a \cdot a}{{b}^{5}} \cdot {c}^{3}, \left(\frac{-0.25 \cdot {a}^{3}}{\frac{b}{\mathsf{fma}\left(16, t_0, 4 \cdot t_0\right)}} - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)\right) - \frac{c}{b}\right)
\end{array}
\end{array}
Initial program 28.7%
Taylor expanded in a around 0 96.7%
Simplified96.7%
Final simplification96.7%
(FPCore (a b c)
:precision binary64
(/
(fma
-4.0
(/ (pow (* a c) 3.0) (pow b 5.0))
(fma
-2.0
(+ (* c (/ a b)) (/ a (/ (/ (pow b 3.0) (* c c)) a)))
(* -0.5 (/ (pow (* a c) 4.0) (/ (pow b 7.0) 20.0)))))
(* a 2.0)))
double code(double a, double b, double c) {
return fma(-4.0, (pow((a * c), 3.0) / pow(b, 5.0)), fma(-2.0, ((c * (a / b)) + (a / ((pow(b, 3.0) / (c * c)) / a))), (-0.5 * (pow((a * c), 4.0) / (pow(b, 7.0) / 20.0))))) / (a * 2.0);
}
function code(a, b, c) return Float64(fma(-4.0, Float64((Float64(a * c) ^ 3.0) / (b ^ 5.0)), fma(-2.0, Float64(Float64(c * Float64(a / b)) + Float64(a / Float64(Float64((b ^ 3.0) / Float64(c * c)) / a))), Float64(-0.5 * Float64((Float64(a * c) ^ 4.0) / Float64((b ^ 7.0) / 20.0))))) / Float64(a * 2.0)) end
code[a_, b_, c_] := N[(N[(-4.0 * N[(N[Power[N[(a * c), $MachinePrecision], 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] + N[(-2.0 * N[(N[(c * N[(a / b), $MachinePrecision]), $MachinePrecision] + N[(a / N[(N[(N[Power[b, 3.0], $MachinePrecision] / N[(c * c), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] / N[(N[Power[b, 7.0], $MachinePrecision] / 20.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-4, \frac{{\left(a \cdot c\right)}^{3}}{{b}^{5}}, \mathsf{fma}\left(-2, c \cdot \frac{a}{b} + \frac{a}{\frac{\frac{{b}^{3}}{c \cdot c}}{a}}, -0.5 \cdot \frac{{\left(a \cdot c\right)}^{4}}{\frac{{b}^{7}}{20}}\right)\right)}{a \cdot 2}
\end{array}
Initial program 28.7%
Taylor expanded in b around inf 96.3%
Simplified96.2%
Taylor expanded in a around 0 96.2%
*-commutative96.2%
distribute-rgt-out96.2%
associate-*l*96.2%
*-commutative96.2%
distribute-rgt-out96.2%
distribute-rgt-out96.2%
associate-*r*96.2%
*-commutative96.2%
associate-/l*96.2%
Simplified96.2%
Taylor expanded in a around 0 96.3%
associate-*l/96.3%
*-commutative96.3%
Simplified96.3%
Final simplification96.3%
(FPCore (a b c)
:precision binary64
(/
(fma
-4.0
(/ (* (* a c) (* (* a c) (* a c))) (pow b 5.0))
(fma
-2.0
(+ (/ a (/ (/ (pow b 3.0) (* c c)) a)) (/ a (/ b c)))
(* -0.5 (/ (pow (* a c) 4.0) (/ (pow b 7.0) 20.0)))))
(* a 2.0)))
double code(double a, double b, double c) {
return fma(-4.0, (((a * c) * ((a * c) * (a * c))) / pow(b, 5.0)), fma(-2.0, ((a / ((pow(b, 3.0) / (c * c)) / a)) + (a / (b / c))), (-0.5 * (pow((a * c), 4.0) / (pow(b, 7.0) / 20.0))))) / (a * 2.0);
}
function code(a, b, c) return Float64(fma(-4.0, Float64(Float64(Float64(a * c) * Float64(Float64(a * c) * Float64(a * c))) / (b ^ 5.0)), fma(-2.0, Float64(Float64(a / Float64(Float64((b ^ 3.0) / Float64(c * c)) / a)) + Float64(a / Float64(b / c))), Float64(-0.5 * Float64((Float64(a * c) ^ 4.0) / Float64((b ^ 7.0) / 20.0))))) / Float64(a * 2.0)) end
code[a_, b_, c_] := N[(N[(-4.0 * N[(N[(N[(a * c), $MachinePrecision] * N[(N[(a * c), $MachinePrecision] * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] + N[(-2.0 * N[(N[(a / N[(N[(N[Power[b, 3.0], $MachinePrecision] / N[(c * c), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision] + N[(a / N[(b / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] / N[(N[Power[b, 7.0], $MachinePrecision] / 20.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-4, \frac{\left(a \cdot c\right) \cdot \left(\left(a \cdot c\right) \cdot \left(a \cdot c\right)\right)}{{b}^{5}}, \mathsf{fma}\left(-2, \frac{a}{\frac{\frac{{b}^{3}}{c \cdot c}}{a}} + \frac{a}{\frac{b}{c}}, -0.5 \cdot \frac{{\left(a \cdot c\right)}^{4}}{\frac{{b}^{7}}{20}}\right)\right)}{a \cdot 2}
\end{array}
Initial program 28.7%
Taylor expanded in b around inf 96.3%
Simplified96.2%
Taylor expanded in a around 0 96.2%
*-commutative96.2%
distribute-rgt-out96.2%
associate-*l*96.2%
*-commutative96.2%
distribute-rgt-out96.2%
distribute-rgt-out96.2%
associate-*r*96.2%
*-commutative96.2%
associate-/l*96.2%
Simplified96.2%
unpow396.2%
Applied egg-rr96.2%
Final simplification96.2%
(FPCore (a b c) :precision binary64 (- (- (/ (* -2.0 (* a a)) (/ (pow b 5.0) (pow c 3.0))) (/ c b)) (* (/ a (pow b 3.0)) (* c c))))
double code(double a, double b, double c) {
return (((-2.0 * (a * a)) / (pow(b, 5.0) / pow(c, 3.0))) - (c / b)) - ((a / pow(b, 3.0)) * (c * 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 * a)) / ((b ** 5.0d0) / (c ** 3.0d0))) - (c / b)) - ((a / (b ** 3.0d0)) * (c * c))
end function
public static double code(double a, double b, double c) {
return (((-2.0 * (a * a)) / (Math.pow(b, 5.0) / Math.pow(c, 3.0))) - (c / b)) - ((a / Math.pow(b, 3.0)) * (c * c));
}
def code(a, b, c): return (((-2.0 * (a * a)) / (math.pow(b, 5.0) / math.pow(c, 3.0))) - (c / b)) - ((a / math.pow(b, 3.0)) * (c * c))
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * Float64(a * a)) / Float64((b ^ 5.0) / (c ^ 3.0))) - Float64(c / b)) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))) end
function tmp = code(a, b, c) tmp = (((-2.0 * (a * a)) / ((b ^ 5.0) / (c ^ 3.0))) - (c / b)) - ((a / (b ^ 3.0)) * (c * c)); end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[(a * a), $MachinePrecision]), $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2 \cdot \left(a \cdot a\right)}{\frac{{b}^{5}}{{c}^{3}}} - \frac{c}{b}\right) - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)
\end{array}
Initial program 28.7%
Taylor expanded in b around inf 95.4%
associate-+r+95.4%
mul-1-neg95.4%
unsub-neg95.4%
mul-1-neg95.4%
unsub-neg95.4%
associate-/l*95.4%
associate-*r/95.4%
unpow295.4%
associate-/l*95.4%
associate-/r/95.4%
unpow295.4%
Simplified95.4%
Final simplification95.4%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* (/ a (pow b 3.0)) (* c c))))
double code(double a, double b, double c) {
return (-c / b) - ((a / pow(b, 3.0)) * (c * 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 / (b ** 3.0d0)) * (c * c))
end function
public static double code(double a, double b, double c) {
return (-c / b) - ((a / Math.pow(b, 3.0)) * (c * c));
}
def code(a, b, c): return (-c / b) - ((a / math.pow(b, 3.0)) * (c * c))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))) end
function tmp = code(a, b, c) tmp = (-c / b) - ((a / (b ^ 3.0)) * (c * c)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)
\end{array}
Initial program 28.7%
Taylor expanded in b around inf 92.4%
mul-1-neg92.4%
unsub-neg92.4%
mul-1-neg92.4%
distribute-neg-frac92.4%
associate-/l*92.4%
associate-/r/92.4%
unpow292.4%
Simplified92.4%
Final simplification92.4%
(FPCore (a b c) :precision binary64 (/ (/ (* 4.0 (* a c)) (- (- b) (+ b (* -2.0 (* c (/ a b)))))) (* a 2.0)))
double code(double a, double b, double c) {
return ((4.0 * (a * c)) / (-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 = ((4.0d0 * (a * c)) / (-b - (b + ((-2.0d0) * (c * (a / b)))))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return ((4.0 * (a * c)) / (-b - (b + (-2.0 * (c * (a / b)))))) / (a * 2.0);
}
def code(a, b, c): return ((4.0 * (a * c)) / (-b - (b + (-2.0 * (c * (a / b)))))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(4.0 * Float64(a * c)) / Float64(Float64(-b) - Float64(b + Float64(-2.0 * Float64(c * Float64(a / b)))))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = ((4.0 * (a * c)) / (-b - (b + (-2.0 * (c * (a / b)))))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[(b + N[(-2.0 * N[(c * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{4 \cdot \left(a \cdot c\right)}{\left(-b\right) - \left(b + -2 \cdot \left(c \cdot \frac{a}{b}\right)\right)}}{a \cdot 2}
\end{array}
Initial program 28.7%
Taylor expanded in b around inf 20.5%
flip-+20.5%
associate-/l*20.5%
associate-/r/20.5%
associate-/l*20.5%
associate-/r/20.5%
associate-/l*20.5%
associate-/r/20.5%
Applied egg-rr20.5%
sqr-neg20.5%
*-commutative20.5%
*-commutative20.5%
*-commutative20.5%
Simplified20.5%
Taylor expanded in b around inf 92.4%
Final simplification92.4%
(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 28.7%
Taylor expanded in b around inf 83.5%
mul-1-neg83.5%
distribute-neg-frac83.5%
Simplified83.5%
Final simplification83.5%
herbie shell --seed 2023275
(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)))