
(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))))
(*
0.3333333333333333
(/
(/
(- (- (pow b 2.0) (pow (- b) 2.0)) t_0)
(+ b (sqrt (- (pow b 2.0) t_0))))
a))))
double code(double a, double b, double c) {
double t_0 = c * (a * 3.0);
return 0.3333333333333333 * ((((pow(b, 2.0) - pow(-b, 2.0)) - t_0) / (b + sqrt((pow(b, 2.0) - t_0)))) / a);
}
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 = 0.3333333333333333d0 * (((((b ** 2.0d0) - (-b ** 2.0d0)) - t_0) / (b + sqrt(((b ** 2.0d0) - t_0)))) / a)
end function
public static double code(double a, double b, double c) {
double t_0 = c * (a * 3.0);
return 0.3333333333333333 * ((((Math.pow(b, 2.0) - Math.pow(-b, 2.0)) - t_0) / (b + Math.sqrt((Math.pow(b, 2.0) - t_0)))) / a);
}
def code(a, b, c): t_0 = c * (a * 3.0) return 0.3333333333333333 * ((((math.pow(b, 2.0) - math.pow(-b, 2.0)) - t_0) / (b + math.sqrt((math.pow(b, 2.0) - t_0)))) / a)
function code(a, b, c) t_0 = Float64(c * Float64(a * 3.0)) return Float64(0.3333333333333333 * Float64(Float64(Float64(Float64((b ^ 2.0) - (Float64(-b) ^ 2.0)) - t_0) / Float64(b + sqrt(Float64((b ^ 2.0) - t_0)))) / a)) end
function tmp = code(a, b, c) t_0 = c * (a * 3.0); tmp = 0.3333333333333333 * (((((b ^ 2.0) - (-b ^ 2.0)) - t_0) / (b + sqrt(((b ^ 2.0) - t_0)))) / a); end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]}, N[(0.3333333333333333 * N[(N[(N[(N[(N[Power[b, 2.0], $MachinePrecision] - N[Power[(-b), 2.0], $MachinePrecision]), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(b + N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := c \cdot \left(a \cdot 3\right)\\
0.3333333333333333 \cdot \frac{\frac{\left({b}^{2} - {\left(-b\right)}^{2}\right) - t\_0}{b + \sqrt{{b}^{2} - t\_0}}}{a}
\end{array}
\end{array}
Initial program 15.9%
expm1-log1p-u15.9%
expm1-undefine10.8%
Applied egg-rr10.8%
expm1-define15.9%
Simplified15.9%
expm1-log1p-u15.9%
add-exp-log15.9%
*-commutative15.9%
Applied egg-rr15.9%
rem-exp-log15.9%
neg-mul-115.9%
*-commutative15.9%
*-commutative15.9%
pow215.9%
fma-undefine15.9%
*-un-lft-identity15.9%
Applied egg-rr15.9%
associate-*r/15.9%
*-commutative15.9%
times-frac15.9%
metadata-eval15.9%
fma-undefine15.9%
neg-mul-115.9%
+-commutative15.9%
unsub-neg15.9%
Simplified15.9%
sub-neg15.9%
pow215.9%
*-commutative15.9%
*-commutative15.9%
+-commutative15.9%
flip-+15.9%
pow215.9%
add-sqr-sqrt16.3%
pow216.3%
*-commutative16.3%
*-commutative16.3%
Applied egg-rr16.3%
associate--r-99.2%
Simplified99.2%
Final simplification99.2%
(FPCore (a b c)
:precision binary64
(*
c
(-
(*
c
(*
a
(-
(*
a
(* c (- (/ (* -1.0546875 (* c a)) (pow b 7.0)) (/ 0.5625 (pow b 5.0)))))
(/ 0.375 (pow b 3.0)))))
(/ 0.5 b))))
double code(double a, double b, double c) {
return c * ((c * (a * ((a * (c * (((-1.0546875 * (c * a)) / pow(b, 7.0)) - (0.5625 / pow(b, 5.0))))) - (0.375 / 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 * ((c * (a * ((a * (c * ((((-1.0546875d0) * (c * a)) / (b ** 7.0d0)) - (0.5625d0 / (b ** 5.0d0))))) - (0.375d0 / (b ** 3.0d0))))) - (0.5d0 / b))
end function
public static double code(double a, double b, double c) {
return c * ((c * (a * ((a * (c * (((-1.0546875 * (c * a)) / Math.pow(b, 7.0)) - (0.5625 / Math.pow(b, 5.0))))) - (0.375 / Math.pow(b, 3.0))))) - (0.5 / b));
}
def code(a, b, c): return c * ((c * (a * ((a * (c * (((-1.0546875 * (c * a)) / math.pow(b, 7.0)) - (0.5625 / math.pow(b, 5.0))))) - (0.375 / math.pow(b, 3.0))))) - (0.5 / b))
function code(a, b, c) return Float64(c * Float64(Float64(c * Float64(a * Float64(Float64(a * Float64(c * Float64(Float64(Float64(-1.0546875 * Float64(c * a)) / (b ^ 7.0)) - Float64(0.5625 / (b ^ 5.0))))) - Float64(0.375 / (b ^ 3.0))))) - Float64(0.5 / b))) end
function tmp = code(a, b, c) tmp = c * ((c * (a * ((a * (c * (((-1.0546875 * (c * a)) / (b ^ 7.0)) - (0.5625 / (b ^ 5.0))))) - (0.375 / (b ^ 3.0))))) - (0.5 / b)); end
code[a_, b_, c_] := N[(c * N[(N[(c * N[(a * N[(N[(a * N[(c * N[(N[(N[(-1.0546875 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision] - N[(0.5625 / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(c \cdot \left(a \cdot \left(a \cdot \left(c \cdot \left(\frac{-1.0546875 \cdot \left(c \cdot a\right)}{{b}^{7}} - \frac{0.5625}{{b}^{5}}\right)\right) - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right)
\end{array}
Initial program 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in c around 0 98.1%
Simplified98.1%
Taylor expanded in a around 0 98.1%
Taylor expanded in c around 0 98.1%
associate-*r/98.1%
associate-*r/98.1%
metadata-eval98.1%
Simplified98.1%
Taylor expanded in b around 0 98.1%
Final simplification98.1%
(FPCore (a b c)
:precision binary64
(+
(* -0.5 (/ c b))
(*
a
(*
(pow c 3.0)
(- (* -0.5625 (/ a (pow b 5.0))) (/ 0.375 (* c (pow b 3.0))))))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * (pow(c, 3.0) * ((-0.5625 * (a / pow(b, 5.0))) - (0.375 / (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 = ((-0.5d0) * (c / b)) + (a * ((c ** 3.0d0) * (((-0.5625d0) * (a / (b ** 5.0d0))) - (0.375d0 / (c * (b ** 3.0d0))))))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * (Math.pow(c, 3.0) * ((-0.5625 * (a / Math.pow(b, 5.0))) - (0.375 / (c * Math.pow(b, 3.0))))));
}
def code(a, b, c): return (-0.5 * (c / b)) + (a * (math.pow(c, 3.0) * ((-0.5625 * (a / math.pow(b, 5.0))) - (0.375 / (c * math.pow(b, 3.0))))))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(a * Float64((c ^ 3.0) * Float64(Float64(-0.5625 * Float64(a / (b ^ 5.0))) - Float64(0.375 / Float64(c * (b ^ 3.0))))))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (a * ((c ^ 3.0) * ((-0.5625 * (a / (b ^ 5.0))) - (0.375 / (c * (b ^ 3.0)))))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[Power[c, 3.0], $MachinePrecision] * N[(N[(-0.5625 * N[(a / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[(c * N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + a \cdot \left({c}^{3} \cdot \left(-0.5625 \cdot \frac{a}{{b}^{5}} - \frac{0.375}{c \cdot {b}^{3}}\right)\right)
\end{array}
Initial program 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in a around 0 97.8%
Taylor expanded in c around inf 97.8%
associate-*r/97.8%
metadata-eval97.8%
*-commutative97.8%
Simplified97.8%
(FPCore (a b c) :precision binary64 (* c (- (* c (* a (- (* -0.5625 (* a (/ c (pow b 5.0)))) (/ 0.375 (pow b 3.0))))) (/ 0.5 b))))
double code(double a, double b, double c) {
return c * ((c * (a * ((-0.5625 * (a * (c / pow(b, 5.0)))) - (0.375 / 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 * ((c * (a * (((-0.5625d0) * (a * (c / (b ** 5.0d0)))) - (0.375d0 / (b ** 3.0d0))))) - (0.5d0 / b))
end function
public static double code(double a, double b, double c) {
return c * ((c * (a * ((-0.5625 * (a * (c / Math.pow(b, 5.0)))) - (0.375 / Math.pow(b, 3.0))))) - (0.5 / b));
}
def code(a, b, c): return c * ((c * (a * ((-0.5625 * (a * (c / math.pow(b, 5.0)))) - (0.375 / math.pow(b, 3.0))))) - (0.5 / b))
function code(a, b, c) return Float64(c * Float64(Float64(c * Float64(a * Float64(Float64(-0.5625 * Float64(a * Float64(c / (b ^ 5.0)))) - Float64(0.375 / (b ^ 3.0))))) - Float64(0.5 / b))) end
function tmp = code(a, b, c) tmp = c * ((c * (a * ((-0.5625 * (a * (c / (b ^ 5.0)))) - (0.375 / (b ^ 3.0))))) - (0.5 / b)); end
code[a_, b_, c_] := N[(c * N[(N[(c * N[(a * N[(N[(-0.5625 * N[(a * N[(c / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(c \cdot \left(a \cdot \left(-0.5625 \cdot \left(a \cdot \frac{c}{{b}^{5}}\right) - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right)
\end{array}
Initial program 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in c around 0 98.1%
Simplified98.1%
Taylor expanded in a around 0 97.4%
associate-/l*97.4%
associate-*r/97.4%
metadata-eval97.4%
Simplified97.4%
(FPCore (a b c) :precision binary64 (/ (fma -0.375 (* a (pow (/ c b) 2.0)) (* c -0.5)) b))
double code(double a, double b, double c) {
return fma(-0.375, (a * pow((c / b), 2.0)), (c * -0.5)) / b;
}
function code(a, b, c) return Float64(fma(-0.375, Float64(a * (Float64(c / b) ^ 2.0)), Float64(c * -0.5)) / b) end
code[a_, b_, c_] := N[(N[(-0.375 * N[(a * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] + N[(c * -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-0.375, a \cdot {\left(\frac{c}{b}\right)}^{2}, c \cdot -0.5\right)}{b}
\end{array}
Initial program 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in a around 0 96.2%
Taylor expanded in b around inf 96.2%
+-commutative96.2%
fma-define96.2%
associate-/l*96.2%
unpow296.2%
unpow296.2%
times-frac96.2%
unpow296.2%
*-commutative96.2%
Simplified96.2%
(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 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in c around 0 95.9%
associate-*r/95.9%
metadata-eval95.9%
Simplified95.9%
Final simplification95.9%
(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 15.9%
/-rgt-identity15.9%
metadata-eval15.9%
Simplified15.9%
Taylor expanded in b around inf 92.1%
herbie shell --seed 2024145
(FPCore (a b c)
:name "Cubic critical, 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) (* (* 3.0 a) c)))) (* 3.0 a)))