
(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 6 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 (* (* c 4.0) a)))
(/
(/ t_0 (* a 2.0))
(-
(- b)
(pow
(/
(fma t_0 (fma b b t_0) (pow b 4.0))
(fma -64.0 (pow (* c a) 3.0) (pow b 6.0)))
-0.5)))))
double code(double a, double b, double c) {
double t_0 = (c * 4.0) * a;
return (t_0 / (a * 2.0)) / (-b - pow((fma(t_0, fma(b, b, t_0), pow(b, 4.0)) / fma(-64.0, pow((c * a), 3.0), pow(b, 6.0))), -0.5));
}
function code(a, b, c) t_0 = Float64(Float64(c * 4.0) * a) return Float64(Float64(t_0 / Float64(a * 2.0)) / Float64(Float64(-b) - (Float64(fma(t_0, fma(b, b, t_0), (b ^ 4.0)) / fma(-64.0, (Float64(c * a) ^ 3.0), (b ^ 6.0))) ^ -0.5))) end
code[a_, b_, c_] := Block[{t$95$0 = N[(N[(c * 4.0), $MachinePrecision] * a), $MachinePrecision]}, N[(N[(t$95$0 / N[(a * 2.0), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Power[N[(N[(t$95$0 * N[(b * b + t$95$0), $MachinePrecision] + N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] / N[(-64.0 * N[Power[N[(c * a), $MachinePrecision], 3.0], $MachinePrecision] + N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(c \cdot 4\right) \cdot a\\
\frac{\frac{t_0}{a \cdot 2}}{\left(-b\right) - {\left(\frac{\mathsf{fma}\left(t_0, \mathsf{fma}\left(b, b, t_0\right), {b}^{4}\right)}{\mathsf{fma}\left(-64, {\left(c \cdot a\right)}^{3}, {b}^{6}\right)}\right)}^{-0.5}}
\end{array}
\end{array}
Initial program 16.1%
*-commutative16.1%
Simplified16.1%
flip3--16.6%
clear-num16.4%
pow216.4%
pow216.4%
pow-prod-up16.6%
metadata-eval16.6%
distribute-rgt-out16.6%
associate-*l*16.6%
+-commutative16.6%
fma-def16.6%
associate-*l*16.6%
Applied egg-rr16.2%
flip-+16.1%
Applied egg-rr17.0%
Taylor expanded in b around 0 99.4%
*-commutative99.4%
associate-*r*99.4%
Simplified99.4%
expm1-log1p-u83.5%
expm1-udef20.5%
Applied egg-rr20.5%
expm1-def83.5%
expm1-log1p99.4%
associate-/r*99.8%
associate-*r*99.8%
*-commutative99.8%
associate-*r*99.8%
associate-*r*99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (a b c)
:precision binary64
(let* ((t_0 (* c (* 4.0 a))))
(/
(/
(* (* c 4.0) a)
(-
(- b)
(pow
(/
(fma t_0 (fma b b t_0) (pow b 4.0))
(+ (pow b 6.0) (* -64.0 (pow (* c a) 3.0))))
-0.5)))
(* a 2.0))))
double code(double a, double b, double c) {
double t_0 = c * (4.0 * a);
return (((c * 4.0) * a) / (-b - pow((fma(t_0, fma(b, b, t_0), pow(b, 4.0)) / (pow(b, 6.0) + (-64.0 * pow((c * a), 3.0)))), -0.5))) / (a * 2.0);
}
function code(a, b, c) t_0 = Float64(c * Float64(4.0 * a)) return Float64(Float64(Float64(Float64(c * 4.0) * a) / Float64(Float64(-b) - (Float64(fma(t_0, fma(b, b, t_0), (b ^ 4.0)) / Float64((b ^ 6.0) + Float64(-64.0 * (Float64(c * a) ^ 3.0)))) ^ -0.5))) / Float64(a * 2.0)) end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(N[(c * 4.0), $MachinePrecision] * a), $MachinePrecision] / N[((-b) - N[Power[N[(N[(t$95$0 * N[(b * b + t$95$0), $MachinePrecision] + N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] / N[(N[Power[b, 6.0], $MachinePrecision] + N[(-64.0 * N[Power[N[(c * a), $MachinePrecision], 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := c \cdot \left(4 \cdot a\right)\\
\frac{\frac{\left(c \cdot 4\right) \cdot a}{\left(-b\right) - {\left(\frac{\mathsf{fma}\left(t_0, \mathsf{fma}\left(b, b, t_0\right), {b}^{4}\right)}{{b}^{6} + -64 \cdot {\left(c \cdot a\right)}^{3}}\right)}^{-0.5}}}{a \cdot 2}
\end{array}
\end{array}
Initial program 16.1%
*-commutative16.1%
Simplified16.1%
flip3--16.6%
clear-num16.4%
pow216.4%
pow216.4%
pow-prod-up16.6%
metadata-eval16.6%
distribute-rgt-out16.6%
associate-*l*16.6%
+-commutative16.6%
fma-def16.6%
associate-*l*16.6%
Applied egg-rr16.2%
flip-+16.1%
Applied egg-rr17.0%
Taylor expanded in b around 0 99.4%
*-commutative99.4%
associate-*r*99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (- (- (* -2.0 (/ (pow c 3.0) (/ (pow b 5.0) (pow a 2.0)))) (/ c b)) (* (/ a (pow b 3.0)) (pow c 2.0))))
double code(double a, double b, double c) {
return ((-2.0 * (pow(c, 3.0) / (pow(b, 5.0) / pow(a, 2.0)))) - (c / b)) - ((a / pow(b, 3.0)) * pow(c, 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 = (((-2.0d0) * ((c ** 3.0d0) / ((b ** 5.0d0) / (a ** 2.0d0)))) - (c / b)) - ((a / (b ** 3.0d0)) * (c ** 2.0d0))
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) / Math.pow(a, 2.0)))) - (c / b)) - ((a / Math.pow(b, 3.0)) * Math.pow(c, 2.0));
}
def code(a, b, c): return ((-2.0 * (math.pow(c, 3.0) / (math.pow(b, 5.0) / math.pow(a, 2.0)))) - (c / b)) - ((a / math.pow(b, 3.0)) * math.pow(c, 2.0))
function code(a, b, c) return Float64(Float64(Float64(-2.0 * Float64((c ^ 3.0) / Float64((b ^ 5.0) / (a ^ 2.0)))) - Float64(c / b)) - Float64(Float64(a / (b ^ 3.0)) * (c ^ 2.0))) end
function tmp = code(a, b, c) tmp = ((-2.0 * ((c ^ 3.0) / ((b ^ 5.0) / (a ^ 2.0)))) - (c / b)) - ((a / (b ^ 3.0)) * (c ^ 2.0)); end
code[a_, b_, c_] := N[(N[(N[(-2.0 * N[(N[Power[c, 3.0], $MachinePrecision] / N[(N[Power[b, 5.0], $MachinePrecision] / N[Power[a, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(-2 \cdot \frac{{c}^{3}}{\frac{{b}^{5}}{{a}^{2}}} - \frac{c}{b}\right) - \frac{a}{{b}^{3}} \cdot {c}^{2}
\end{array}
Initial program 16.1%
*-commutative16.1%
Simplified16.1%
Taylor expanded in b around inf 96.8%
associate-+r+96.8%
mul-1-neg96.8%
unsub-neg96.8%
mul-1-neg96.8%
unsub-neg96.8%
*-commutative96.8%
associate-/l*96.8%
associate-/l*96.8%
associate-/r/96.8%
Simplified96.8%
Final simplification96.8%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* (/ a (pow b 3.0)) (pow c 2.0))))
double code(double a, double b, double c) {
return (-c / b) - ((a / pow(b, 3.0)) * pow(c, 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 ** 3.0d0)) * (c ** 2.0d0))
end function
public static double code(double a, double b, double c) {
return (-c / b) - ((a / Math.pow(b, 3.0)) * Math.pow(c, 2.0));
}
def code(a, b, c): return (-c / b) - ((a / math.pow(b, 3.0)) * math.pow(c, 2.0))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(Float64(a / (b ^ 3.0)) * (c ^ 2.0))) end
function tmp = code(a, b, c) tmp = (-c / b) - ((a / (b ^ 3.0)) * (c ^ 2.0)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{a}{{b}^{3}} \cdot {c}^{2}
\end{array}
Initial program 16.1%
*-commutative16.1%
Simplified16.1%
Taylor expanded in b around inf 95.3%
mul-1-neg95.3%
unsub-neg95.3%
mul-1-neg95.3%
distribute-neg-frac95.3%
associate-/l*95.3%
associate-/r/95.3%
Simplified95.3%
Final simplification95.3%
(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 16.1%
*-commutative16.1%
Simplified16.1%
Taylor expanded in b around inf 91.4%
mul-1-neg91.4%
distribute-neg-frac91.4%
Simplified91.4%
Final simplification91.4%
(FPCore (a b c) :precision binary64 0.0)
double code(double a, double b, double c) {
return 0.0;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 0.0d0
end function
public static double code(double a, double b, double c) {
return 0.0;
}
def code(a, b, c): return 0.0
function code(a, b, c) return 0.0 end
function tmp = code(a, b, c) tmp = 0.0; end
code[a_, b_, c_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 16.1%
*-commutative16.1%
Simplified16.1%
flip3--16.6%
clear-num16.4%
pow216.4%
pow216.4%
pow-prod-up16.6%
metadata-eval16.6%
distribute-rgt-out16.6%
associate-*l*16.6%
+-commutative16.6%
fma-def16.6%
associate-*l*16.6%
Applied egg-rr16.2%
flip-+16.1%
Applied egg-rr17.0%
Taylor expanded in b around 0 99.4%
*-commutative99.4%
associate-*r*99.4%
Simplified99.4%
Taylor expanded in b around inf 3.3%
distribute-rgt-out3.3%
metadata-eval3.3%
mul0-rgt3.3%
Simplified3.3%
Final simplification3.3%
herbie shell --seed 2023333
(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)))