
(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 (* 4.0 (* a c))))
(if (<= (/ (- (sqrt (- (* b b) (* (* 4.0 a) c))) b) (* a 2.0)) -200.0)
(/
(-
(sqrt
(/
(- (pow b 6.0) (* 64.0 (* (pow a 3.0) (pow c 3.0))))
(+ (pow b 4.0) (* t_0 (fma b b t_0)))))
b)
(* a 2.0))
(fma
-2.0
(/ (pow c 3.0) (/ (pow b 5.0) (* a a)))
(-
(fma
-0.25
(/ (* (pow (* a c) 4.0) 20.0) (* a (pow b 7.0)))
(/ (- a) (/ (pow b 3.0) (* c c))))
(/ c b))))))
double code(double a, double b, double c) {
double t_0 = 4.0 * (a * c);
double tmp;
if (((sqrt(((b * b) - ((4.0 * a) * c))) - b) / (a * 2.0)) <= -200.0) {
tmp = (sqrt(((pow(b, 6.0) - (64.0 * (pow(a, 3.0) * pow(c, 3.0)))) / (pow(b, 4.0) + (t_0 * fma(b, b, t_0))))) - b) / (a * 2.0);
} else {
tmp = fma(-2.0, (pow(c, 3.0) / (pow(b, 5.0) / (a * a))), (fma(-0.25, ((pow((a * c), 4.0) * 20.0) / (a * pow(b, 7.0))), (-a / (pow(b, 3.0) / (c * c)))) - (c / b)));
}
return tmp;
}
function code(a, b, c) t_0 = Float64(4.0 * Float64(a * c)) tmp = 0.0 if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c))) - b) / Float64(a * 2.0)) <= -200.0) tmp = Float64(Float64(sqrt(Float64(Float64((b ^ 6.0) - Float64(64.0 * Float64((a ^ 3.0) * (c ^ 3.0)))) / Float64((b ^ 4.0) + Float64(t_0 * fma(b, b, t_0))))) - b) / Float64(a * 2.0)); else tmp = fma(-2.0, Float64((c ^ 3.0) / Float64((b ^ 5.0) / Float64(a * a))), Float64(fma(-0.25, Float64(Float64((Float64(a * c) ^ 4.0) * 20.0) / Float64(a * (b ^ 7.0))), Float64(Float64(-a) / Float64((b ^ 3.0) / Float64(c * c)))) - Float64(c / b))); end return tmp end
code[a_, b_, c_] := Block[{t$95$0 = N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], -200.0], N[(N[(N[Sqrt[N[(N[(N[Power[b, 6.0], $MachinePrecision] - N[(64.0 * N[(N[Power[a, 3.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[Power[b, 4.0], $MachinePrecision] + N[(t$95$0 * N[(b * b + t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(-2.0 * N[(N[Power[c, 3.0], $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.25 * N[(N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] * 20.0), $MachinePrecision] / N[(a * N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[((-a) / N[(N[Power[b, 3.0], $MachinePrecision] / N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 4 \cdot \left(a \cdot c\right)\\
\mathbf{if}\;\frac{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}{a \cdot 2} \leq -200:\\
\;\;\;\;\frac{\sqrt{\frac{{b}^{6} - 64 \cdot \left({a}^{3} \cdot {c}^{3}\right)}{{b}^{4} + t_0 \cdot \mathsf{fma}\left(b, b, t_0\right)}} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-2, \frac{{c}^{3}}{\frac{{b}^{5}}{a \cdot a}}, \mathsf{fma}\left(-0.25, \frac{{\left(a \cdot c\right)}^{4} \cdot 20}{a \cdot {b}^{7}}, \frac{-a}{\frac{{b}^{3}}{c \cdot c}}\right) - \frac{c}{b}\right)\\
\end{array}
\end{array}
if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 4 a) c)))) (*.f64 2 a)) < -200Initial program 92.5%
flip3--91.5%
pow291.5%
pow-pow91.9%
metadata-eval91.9%
associate-*l*91.9%
pow291.9%
pow291.9%
pow-prod-up92.6%
metadata-eval92.6%
distribute-rgt-out92.6%
associate-*l*92.6%
+-commutative92.6%
fma-def92.6%
associate-*l*92.6%
Applied egg-rr92.6%
Taylor expanded in a around 0 92.8%
if -200 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 4 a) c)))) (*.f64 2 a)) Initial program 53.1%
Taylor expanded in b around inf 92.6%
Simplified92.6%
Taylor expanded in a around 0 92.6%
distribute-rgt-out92.6%
associate-*r*92.6%
metadata-eval92.6%
pow-sqr92.6%
unpow292.6%
unpow292.6%
metadata-eval92.6%
pow-sqr92.6%
unpow292.6%
unpow292.6%
swap-sqr92.6%
*-commutative92.6%
swap-sqr92.6%
*-commutative92.6%
swap-sqr92.6%
unpow292.6%
unpow292.6%
pow-sqr92.6%
*-commutative92.6%
metadata-eval92.6%
metadata-eval92.6%
Simplified92.6%
Final simplification92.6%
(FPCore (a b c)
:precision binary64
(if (<= b 24.2)
(/ (- (sqrt (fma b b (* c (* a -4.0)))) b) (* a 2.0))
(-
(fma -2.0 (/ (pow c 3.0) (/ (pow b 5.0) (* a a))) (/ (- c) b))
(/ a (/ (pow b 3.0) (* c c))))))
double code(double a, double b, double c) {
double tmp;
if (b <= 24.2) {
tmp = (sqrt(fma(b, b, (c * (a * -4.0)))) - b) / (a * 2.0);
} else {
tmp = fma(-2.0, (pow(c, 3.0) / (pow(b, 5.0) / (a * a))), (-c / b)) - (a / (pow(b, 3.0) / (c * c)));
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= 24.2) tmp = Float64(Float64(sqrt(fma(b, b, Float64(c * Float64(a * -4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(fma(-2.0, Float64((c ^ 3.0) / Float64((b ^ 5.0) / Float64(a * a))), Float64(Float64(-c) / b)) - Float64(a / Float64((b ^ 3.0) / Float64(c * c)))); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, 24.2], N[(N[(N[Sqrt[N[(b * b + N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * N[(N[Power[c, 3.0], $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[((-c) / b), $MachinePrecision]), $MachinePrecision] - N[(a / N[(N[Power[b, 3.0], $MachinePrecision] / N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 24.2:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-2, \frac{{c}^{3}}{\frac{{b}^{5}}{a \cdot a}}, \frac{-c}{b}\right) - \frac{a}{\frac{{b}^{3}}{c \cdot c}}\\
\end{array}
\end{array}
if b < 24.1999999999999993Initial program 81.1%
Simplified81.2%
if 24.1999999999999993 < b Initial program 46.3%
Taylor expanded in b around inf 93.6%
associate-+r+93.6%
mul-1-neg93.6%
unsub-neg93.6%
fma-def93.6%
*-commutative93.6%
associate-/l*93.6%
unpow293.6%
mul-1-neg93.6%
distribute-neg-frac93.6%
associate-/l*93.6%
unpow293.6%
Simplified93.6%
Final simplification90.4%
(FPCore (a b c) :precision binary64 (if (<= b 24.2) (/ (- (sqrt (fma b b (* c (* a -4.0)))) b) (* a 2.0)) (- (/ (- c) b) (* (/ a b) (pow (/ c b) 2.0)))))
double code(double a, double b, double c) {
double tmp;
if (b <= 24.2) {
tmp = (sqrt(fma(b, b, (c * (a * -4.0)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / b) * pow((c / b), 2.0));
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= 24.2) tmp = Float64(Float64(sqrt(fma(b, b, Float64(c * Float64(a * -4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(Float64(Float64(-c) / b) - Float64(Float64(a / b) * (Float64(c / b) ^ 2.0))); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, 24.2], N[(N[(N[Sqrt[N[(b * b + N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / b), $MachinePrecision] * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 24.2:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{-c}{b} - \frac{a}{b} \cdot {\left(\frac{c}{b}\right)}^{2}\\
\end{array}
\end{array}
if b < 24.1999999999999993Initial program 81.1%
Simplified81.2%
if 24.1999999999999993 < b Initial program 46.3%
Taylor expanded in b around inf 89.3%
distribute-lft-out89.3%
associate-/l*89.3%
pow-prod-down89.3%
*-commutative89.3%
Applied egg-rr89.3%
associate-/r/89.3%
fma-def89.4%
*-commutative89.4%
Simplified89.4%
Taylor expanded in a around 0 89.5%
mul-1-neg89.5%
unsub-neg89.5%
associate-*r/89.5%
mul-1-neg89.5%
cube-mult89.5%
unpow289.5%
times-frac89.5%
unpow289.5%
unpow289.5%
times-frac89.5%
unpow289.5%
Simplified89.5%
Final simplification87.4%
(FPCore (a b c) :precision binary64 (if (<= b 24.2) (/ (- (sqrt (- (* b b) (* 4.0 (* a c)))) b) (* a 2.0)) (- (/ (- c) b) (* (/ a b) (pow (/ c b) 2.0)))))
double code(double a, double b, double c) {
double tmp;
if (b <= 24.2) {
tmp = (sqrt(((b * b) - (4.0 * (a * c)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / b) * pow((c / b), 2.0));
}
return tmp;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8) :: tmp
if (b <= 24.2d0) then
tmp = (sqrt(((b * b) - (4.0d0 * (a * c)))) - b) / (a * 2.0d0)
else
tmp = (-c / b) - ((a / b) * ((c / b) ** 2.0d0))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 24.2) {
tmp = (Math.sqrt(((b * b) - (4.0 * (a * c)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / b) * Math.pow((c / b), 2.0));
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 24.2: tmp = (math.sqrt(((b * b) - (4.0 * (a * c)))) - b) / (a * 2.0) else: tmp = (-c / b) - ((a / b) * math.pow((c / b), 2.0)) return tmp
function code(a, b, c) tmp = 0.0 if (b <= 24.2) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(4.0 * Float64(a * c)))) - b) / Float64(a * 2.0)); else tmp = Float64(Float64(Float64(-c) / b) - Float64(Float64(a / b) * (Float64(c / b) ^ 2.0))); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 24.2) tmp = (sqrt(((b * b) - (4.0 * (a * c)))) - b) / (a * 2.0); else tmp = (-c / b) - ((a / b) * ((c / b) ^ 2.0)); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 24.2], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / b), $MachinePrecision] * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 24.2:\\
\;\;\;\;\frac{\sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{-c}{b} - \frac{a}{b} \cdot {\left(\frac{c}{b}\right)}^{2}\\
\end{array}
\end{array}
if b < 24.1999999999999993Initial program 81.1%
Simplified81.2%
*-commutative81.2%
metadata-eval81.2%
distribute-lft-neg-in81.2%
distribute-rgt-neg-in81.2%
*-commutative81.2%
fma-neg81.1%
associate-*l*81.1%
Applied egg-rr81.1%
if 24.1999999999999993 < b Initial program 46.3%
Taylor expanded in b around inf 89.3%
distribute-lft-out89.3%
associate-/l*89.3%
pow-prod-down89.3%
*-commutative89.3%
Applied egg-rr89.3%
associate-/r/89.3%
fma-def89.4%
*-commutative89.4%
Simplified89.4%
Taylor expanded in a around 0 89.5%
mul-1-neg89.5%
unsub-neg89.5%
associate-*r/89.5%
mul-1-neg89.5%
cube-mult89.5%
unpow289.5%
times-frac89.5%
unpow289.5%
unpow289.5%
times-frac89.5%
unpow289.5%
Simplified89.5%
Final simplification87.3%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* (/ a b) (pow (/ c b) 2.0))))
double code(double a, double b, double c) {
return (-c / b) - ((a / b) * pow((c / b), 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 / b) - ((a / b) * ((c / b) ** 2.0d0))
end function
public static double code(double a, double b, double c) {
return (-c / b) - ((a / b) * Math.pow((c / b), 2.0));
}
def code(a, b, c): return (-c / b) - ((a / b) * math.pow((c / b), 2.0))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(Float64(a / b) * (Float64(c / b) ^ 2.0))) end
function tmp = code(a, b, c) tmp = (-c / b) - ((a / b) * ((c / b) ^ 2.0)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / b), $MachinePrecision] * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{a}{b} \cdot {\left(\frac{c}{b}\right)}^{2}
\end{array}
Initial program 55.1%
Taylor expanded in b around inf 82.2%
distribute-lft-out82.2%
associate-/l*82.2%
pow-prod-down82.2%
*-commutative82.2%
Applied egg-rr82.2%
associate-/r/82.1%
fma-def82.2%
*-commutative82.2%
Simplified82.2%
Taylor expanded in a around 0 82.3%
mul-1-neg82.3%
unsub-neg82.3%
associate-*r/82.3%
mul-1-neg82.3%
cube-mult82.3%
unpow282.3%
times-frac82.3%
unpow282.3%
unpow282.3%
times-frac82.3%
unpow282.3%
Simplified82.3%
Final simplification82.3%
(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 55.1%
Taylor expanded in b around inf 64.8%
mul-1-neg64.8%
distribute-neg-frac64.8%
Simplified64.8%
Final simplification64.8%
(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(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 55.1%
Taylor expanded in b around -inf 11.6%
+-commutative11.6%
mul-1-neg11.6%
unsub-neg11.6%
Simplified11.6%
Taylor expanded in c around inf 1.6%
Final simplification1.6%
herbie shell --seed 2023279
(FPCore (a b c)
:name "Quadratic roots, narrow range"
:precision binary64
:pre (and (and (and (< 1.0536712127723509e-8 a) (< a 94906265.62425156)) (and (< 1.0536712127723509e-8 b) (< b 94906265.62425156))) (and (< 1.0536712127723509e-8 c) (< c 94906265.62425156)))
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))