
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \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) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}
(FPCore (a b c) :precision binary64 (let* ((t_0 (* c (* a 3.0)))) (/ (/ t_0 (- (- b) (sqrt (- (pow b 2.0) t_0)))) (* a 3.0))))
double code(double a, double b, double c) {
double t_0 = c * (a * 3.0);
return (t_0 / (-b - sqrt((pow(b, 2.0) - t_0)))) / (a * 3.0);
}
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 = c * (a * 3.0d0)
code = (t_0 / (-b - sqrt(((b ** 2.0d0) - t_0)))) / (a * 3.0d0)
end function
public static double code(double a, double b, double c) {
double t_0 = c * (a * 3.0);
return (t_0 / (-b - Math.sqrt((Math.pow(b, 2.0) - t_0)))) / (a * 3.0);
}
def code(a, b, c): t_0 = c * (a * 3.0) return (t_0 / (-b - math.sqrt((math.pow(b, 2.0) - t_0)))) / (a * 3.0)
function code(a, b, c) t_0 = Float64(c * Float64(a * 3.0)) return Float64(Float64(t_0 / Float64(Float64(-b) - sqrt(Float64((b ^ 2.0) - t_0)))) / Float64(a * 3.0)) end
function tmp = code(a, b, c) t_0 = c * (a * 3.0); tmp = (t_0 / (-b - sqrt(((b ^ 2.0) - t_0)))) / (a * 3.0); end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$0 / N[((-b) - N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := c \cdot \left(a \cdot 3\right)\\
\frac{\frac{t\_0}{\left(-b\right) - \sqrt{{b}^{2} - t\_0}}}{a \cdot 3}
\end{array}
\end{array}
Initial program 30.3%
neg-sub030.3%
flip--30.4%
metadata-eval30.4%
pow230.4%
add-sqr-sqrt30.3%
sqrt-prod30.4%
sqr-neg30.4%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod30.4%
sqr-neg30.4%
sqrt-prod30.3%
add-sqr-sqrt30.4%
Applied egg-rr30.4%
neg-sub030.4%
Simplified30.4%
flip-+30.3%
Applied egg-rr31.0%
associate--r-99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (/ (/ (* 3.0 (* a (- c))) (+ b (sqrt (- (pow b 2.0) (* c (* a 3.0)))))) (* a 3.0)))
double code(double a, double b, double c) {
return ((3.0 * (a * -c)) / (b + sqrt((pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 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 = ((3.0d0 * (a * -c)) / (b + sqrt(((b ** 2.0d0) - (c * (a * 3.0d0)))))) / (a * 3.0d0)
end function
public static double code(double a, double b, double c) {
return ((3.0 * (a * -c)) / (b + Math.sqrt((Math.pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0);
}
def code(a, b, c): return ((3.0 * (a * -c)) / (b + math.sqrt((math.pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0)
function code(a, b, c) return Float64(Float64(Float64(3.0 * Float64(a * Float64(-c))) / Float64(b + sqrt(Float64((b ^ 2.0) - Float64(c * Float64(a * 3.0)))))) / Float64(a * 3.0)) end
function tmp = code(a, b, c) tmp = ((3.0 * (a * -c)) / (b + sqrt(((b ^ 2.0) - (c * (a * 3.0)))))) / (a * 3.0); end
code[a_, b_, c_] := N[(N[(N[(3.0 * N[(a * (-c)), $MachinePrecision]), $MachinePrecision] / N[(b + N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] - N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{3 \cdot \left(a \cdot \left(-c\right)\right)}{b + \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3}
\end{array}
Initial program 30.3%
neg-sub030.3%
flip--30.4%
metadata-eval30.4%
pow230.4%
add-sqr-sqrt30.3%
sqrt-prod30.4%
sqr-neg30.4%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod30.4%
sqr-neg30.4%
sqrt-prod30.3%
add-sqr-sqrt30.4%
Applied egg-rr30.4%
neg-sub030.4%
Simplified30.4%
flip-+30.3%
Applied egg-rr31.0%
associate--r-99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in b around 0 99.1%
Final simplification99.1%
(FPCore (a b c) :precision binary64 (/ (fma -0.5 c (* -0.375 (* a (pow (/ c b) 2.0)))) b))
double code(double a, double b, double c) {
return fma(-0.5, c, (-0.375 * (a * pow((c / b), 2.0)))) / b;
}
function code(a, b, c) return Float64(fma(-0.5, c, Float64(-0.375 * Float64(a * (Float64(c / b) ^ 2.0)))) / b) end
code[a_, b_, c_] := N[(N[(-0.5 * c + N[(-0.375 * N[(a * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot {\left(\frac{c}{b}\right)}^{2}\right)\right)}{b}
\end{array}
Initial program 30.3%
Simplified30.4%
Taylor expanded in a around 0 94.0%
Taylor expanded in b around inf 91.1%
fma-define91.1%
associate-/l*91.1%
unpow291.1%
unpow291.1%
times-frac91.1%
unpow291.1%
Simplified91.1%
(FPCore (a b c) :precision binary64 (* c (/ (- (* -0.375 (/ (* c a) (pow b 2.0))) 0.5) b)))
double code(double a, double b, double c) {
return c * (((-0.375 * ((c * a) / pow(b, 2.0))) - 0.5) / 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 * ((((-0.375d0) * ((c * a) / (b ** 2.0d0))) - 0.5d0) / b)
end function
public static double code(double a, double b, double c) {
return c * (((-0.375 * ((c * a) / Math.pow(b, 2.0))) - 0.5) / b);
}
def code(a, b, c): return c * (((-0.375 * ((c * a) / math.pow(b, 2.0))) - 0.5) / b)
function code(a, b, c) return Float64(c * Float64(Float64(Float64(-0.375 * Float64(Float64(c * a) / (b ^ 2.0))) - 0.5) / b)) end
function tmp = code(a, b, c) tmp = c * (((-0.375 * ((c * a) / (b ^ 2.0))) - 0.5) / b); end
code[a_, b_, c_] := N[(c * N[(N[(N[(-0.375 * N[(N[(c * a), $MachinePrecision] / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{-0.375 \cdot \frac{c \cdot a}{{b}^{2}} - 0.5}{b}
\end{array}
Initial program 30.3%
Simplified30.4%
Taylor expanded in c around 0 93.7%
Taylor expanded in b around inf 90.8%
Final simplification90.8%
(FPCore (a b c) :precision binary64 (* c (- (* -0.375 (/ (* c a) (pow b 3.0))) (/ 0.5 b))))
double code(double a, double b, double c) {
return c * ((-0.375 * ((c * a) / pow(b, 3.0))) - (0.5 / 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 * (((-0.375d0) * ((c * a) / (b ** 3.0d0))) - (0.5d0 / b))
end function
public static double code(double a, double b, double c) {
return c * ((-0.375 * ((c * a) / Math.pow(b, 3.0))) - (0.5 / b));
}
def code(a, b, c): return c * ((-0.375 * ((c * a) / math.pow(b, 3.0))) - (0.5 / b))
function code(a, b, c) return Float64(c * Float64(Float64(-0.375 * Float64(Float64(c * a) / (b ^ 3.0))) - Float64(0.5 / b))) end
function tmp = code(a, b, c) tmp = c * ((-0.375 * ((c * a) / (b ^ 3.0))) - (0.5 / b)); end
code[a_, b_, c_] := N[(c * N[(N[(-0.375 * N[(N[(c * a), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(-0.375 \cdot \frac{c \cdot a}{{b}^{3}} - \frac{0.5}{b}\right)
\end{array}
Initial program 30.3%
Simplified30.4%
Taylor expanded in c around 0 90.8%
associate-*r/90.8%
metadata-eval90.8%
Simplified90.8%
Final simplification90.8%
(FPCore (a b c) :precision binary64 (* -0.5 (/ c b)))
double code(double a, double b, double c) {
return -0.5 * (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 = (-0.5d0) * (c / b)
end function
public static double code(double a, double b, double c) {
return -0.5 * (c / b);
}
def code(a, b, c): return -0.5 * (c / b)
function code(a, b, c) return Float64(-0.5 * Float64(c / b)) end
function tmp = code(a, b, c) tmp = -0.5 * (c / b); end
code[a_, b_, c_] := N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b}
\end{array}
Initial program 30.3%
Simplified30.4%
Taylor expanded in b around inf 82.3%
(FPCore (a b c) :precision binary64 (/ 0.0 a))
double code(double a, double b, double c) {
return 0.0 / a;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 0.0d0 / a
end function
public static double code(double a, double b, double c) {
return 0.0 / a;
}
def code(a, b, c): return 0.0 / a
function code(a, b, c) return Float64(0.0 / a) end
function tmp = code(a, b, c) tmp = 0.0 / a; end
code[a_, b_, c_] := N[(0.0 / a), $MachinePrecision]
\begin{array}{l}
\\
\frac{0}{a}
\end{array}
Initial program 30.3%
neg-sub030.3%
flip--30.4%
metadata-eval30.4%
pow230.4%
add-sqr-sqrt30.3%
sqrt-prod30.4%
sqr-neg30.4%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod30.4%
sqr-neg30.4%
sqrt-prod30.3%
add-sqr-sqrt30.4%
Applied egg-rr30.4%
neg-sub030.4%
Simplified30.4%
Taylor expanded in a around 0 3.2%
associate-*r/3.2%
distribute-rgt1-in3.2%
metadata-eval3.2%
mul0-lft3.2%
metadata-eval3.2%
Simplified3.2%
herbie shell --seed 2024173
(FPCore (a b c)
:name "Cubic critical, 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) (* (* 3.0 a) c)))) (* 3.0 a)))