
(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 -1.0 (/ (* a (* c c)) (pow b 3.0)) (fma -0.25 (* (/ (pow (* a c) 4.0) a) (/ 20.0 (pow b 7.0))) (fma -1.0 (/ c b) (* -2.0 (/ (* (pow c 3.0) (* a a)) (pow b 5.0)))))))
double code(double a, double b, double c) {
return fma(-1.0, ((a * (c * c)) / pow(b, 3.0)), fma(-0.25, ((pow((a * c), 4.0) / a) * (20.0 / pow(b, 7.0))), fma(-1.0, (c / b), (-2.0 * ((pow(c, 3.0) * (a * a)) / pow(b, 5.0))))));
}
function code(a, b, c) return fma(-1.0, Float64(Float64(a * Float64(c * c)) / (b ^ 3.0)), fma(-0.25, Float64(Float64((Float64(a * c) ^ 4.0) / a) * Float64(20.0 / (b ^ 7.0))), fma(-1.0, Float64(c / b), Float64(-2.0 * Float64(Float64((c ^ 3.0) * Float64(a * a)) / (b ^ 5.0)))))) end
code[a_, b_, c_] := N[(-1.0 * N[(N[(a * N[(c * c), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] + N[(-0.25 * N[(N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] / a), $MachinePrecision] * N[(20.0 / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-1.0 * N[(c / b), $MachinePrecision] + N[(-2.0 * N[(N[(N[Power[c, 3.0], $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-1, \frac{a \cdot \left(c \cdot c\right)}{{b}^{3}}, \mathsf{fma}\left(-0.25, \frac{{\left(a \cdot c\right)}^{4}}{a} \cdot \frac{20}{{b}^{7}}, \mathsf{fma}\left(-1, \frac{c}{b}, -2 \cdot \frac{{c}^{3} \cdot \left(a \cdot a\right)}{{b}^{5}}\right)\right)\right)
\end{array}
Initial program 32.8%
neg-sub032.8%
associate-+l-32.8%
sub0-neg32.8%
neg-mul-132.8%
associate-*l/32.8%
*-commutative32.8%
associate-/r*32.8%
/-rgt-identity32.8%
metadata-eval32.8%
Simplified32.8%
Taylor expanded in b around inf 94.9%
fma-def94.9%
*-commutative94.9%
unpow294.9%
fma-def94.9%
Simplified94.9%
Taylor expanded in c around 0 94.9%
+-commutative94.9%
distribute-rgt-out94.9%
associate-*r*94.9%
times-frac94.9%
Simplified94.9%
Final simplification94.9%
(FPCore (a b c)
:precision binary64
(-
(-
(fma
-0.25
(* 20.0 (/ (pow c 4.0) (/ (pow b 7.0) (pow a 3.0))))
(* -2.0 (/ (* a a) (/ (pow b 5.0) (pow c 3.0)))))
(/ c b))
(/ (* c (* a c)) (pow b 3.0))))
double code(double a, double b, double c) {
return (fma(-0.25, (20.0 * (pow(c, 4.0) / (pow(b, 7.0) / pow(a, 3.0)))), (-2.0 * ((a * a) / (pow(b, 5.0) / pow(c, 3.0))))) - (c / b)) - ((c * (a * c)) / pow(b, 3.0));
}
function code(a, b, c) return Float64(Float64(fma(-0.25, Float64(20.0 * Float64((c ^ 4.0) / Float64((b ^ 7.0) / (a ^ 3.0)))), Float64(-2.0 * Float64(Float64(a * a) / Float64((b ^ 5.0) / (c ^ 3.0))))) - Float64(c / b)) - Float64(Float64(c * Float64(a * c)) / (b ^ 3.0))) end
code[a_, b_, c_] := N[(N[(N[(-0.25 * N[(20.0 * N[(N[Power[c, 4.0], $MachinePrecision] / N[(N[Power[b, 7.0], $MachinePrecision] / N[Power[a, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-2.0 * N[(N[(a * a), $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(c * N[(a * c), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(-0.25, 20 \cdot \frac{{c}^{4}}{\frac{{b}^{7}}{{a}^{3}}}, -2 \cdot \frac{a \cdot a}{\frac{{b}^{5}}{{c}^{3}}}\right) - \frac{c}{b}\right) - \frac{c \cdot \left(a \cdot c\right)}{{b}^{3}}
\end{array}
Initial program 32.8%
neg-sub032.8%
associate-+l-32.8%
sub0-neg32.8%
neg-mul-132.8%
associate-*l/32.8%
*-commutative32.8%
associate-/r*32.8%
/-rgt-identity32.8%
metadata-eval32.8%
Simplified32.8%
Taylor expanded in a around 0 94.9%
Simplified94.9%
Taylor expanded in c around 0 94.9%
associate-/l*94.9%
Simplified94.9%
Final simplification94.9%
(FPCore (a b c) :precision binary64 (- (- (/ (* -2.0 (pow c 3.0)) (/ (pow b 5.0) (* a a))) (/ c b)) (* c (/ (* a c) (pow b 3.0)))))
double code(double a, double b, double c) {
return (((-2.0 * pow(c, 3.0)) / (pow(b, 5.0) / (a * a))) - (c / b)) - (c * ((a * c) / 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) * (c ** 3.0d0)) / ((b ** 5.0d0) / (a * a))) - (c / b)) - (c * ((a * c) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (((-2.0 * Math.pow(c, 3.0)) / (Math.pow(b, 5.0) / (a * a))) - (c / b)) - (c * ((a * c) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (((-2.0 * math.pow(c, 3.0)) / (math.pow(b, 5.0) / (a * a))) - (c / b)) - (c * ((a * c) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * (c ^ 3.0)) / Float64((b ^ 5.0) / Float64(a * a))) - Float64(c / b)) - Float64(c * Float64(Float64(a * c) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (((-2.0 * (c ^ 3.0)) / ((b ^ 5.0) / (a * a))) - (c / b)) - (c * ((a * c) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(c * N[(N[(a * c), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2 \cdot {c}^{3}}{\frac{{b}^{5}}{a \cdot a}} - \frac{c}{b}\right) - c \cdot \frac{a \cdot c}{{b}^{3}}
\end{array}
Initial program 32.8%
neg-sub032.8%
associate-+l-32.8%
sub0-neg32.8%
neg-mul-132.8%
associate-*l/32.8%
*-commutative32.8%
associate-/r*32.8%
/-rgt-identity32.8%
metadata-eval32.8%
Simplified32.8%
Taylor expanded in b around inf 92.9%
associate-+r+92.9%
distribute-lft-out92.9%
fma-def92.9%
*-commutative92.9%
associate-/l*92.9%
*-commutative92.9%
associate-/l*92.9%
unpow292.9%
unpow292.9%
cube-prod92.9%
Simplified92.9%
Taylor expanded in a around 0 93.4%
+-commutative93.4%
mul-1-neg93.4%
unpow293.4%
associate-*r*93.4%
unsub-neg93.4%
Simplified93.4%
Final simplification93.4%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* c (/ (* a c) (pow b 3.0)))))
double code(double a, double b, double c) {
return (-c / b) - (c * ((a * c) / 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 = (-c / b) - (c * ((a * c) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (-c / b) - (c * ((a * c) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (-c / b) - (c * ((a * c) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(c * Float64(Float64(a * c) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (-c / b) - (c * ((a * c) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(c * N[(N[(a * c), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - c \cdot \frac{a \cdot c}{{b}^{3}}
\end{array}
Initial program 32.8%
*-commutative32.8%
+-commutative32.8%
unsub-neg32.8%
fma-neg32.8%
associate-*l*32.8%
*-commutative32.8%
distribute-rgt-neg-in32.8%
metadata-eval32.8%
Simplified32.8%
fma-udef32.8%
*-commutative32.8%
Applied egg-rr32.8%
Taylor expanded in b around inf 90.5%
+-commutative90.5%
mul-1-neg90.5%
unsub-neg90.5%
mul-1-neg90.5%
unpow290.5%
associate-*r*90.5%
*-rgt-identity90.5%
associate-*r/90.5%
associate-*l*90.5%
associate-*r/90.5%
*-commutative90.5%
*-lft-identity90.5%
Simplified90.5%
Final simplification90.5%
(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 32.8%
neg-sub032.8%
associate-+l-32.8%
sub0-neg32.8%
neg-mul-132.8%
associate-*l/32.8%
*-commutative32.8%
associate-/r*32.8%
/-rgt-identity32.8%
metadata-eval32.8%
Simplified32.8%
Taylor expanded in b around inf 80.4%
associate-*r/80.4%
neg-mul-180.4%
Simplified80.4%
Final simplification80.4%
herbie shell --seed 2023193
(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)))