
(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 (/ (/ (* c (* a 3.0)) (- (- b) (sqrt (fma b b (* c (* a (- 3.0))))))) (* a 3.0)))
double code(double a, double b, double c) {
return ((c * (a * 3.0)) / (-b - sqrt(fma(b, b, (c * (a * -3.0)))))) / (a * 3.0);
}
function code(a, b, c) return Float64(Float64(Float64(c * Float64(a * 3.0)) / Float64(Float64(-b) - sqrt(fma(b, b, Float64(c * Float64(a * Float64(-3.0))))))) / Float64(a * 3.0)) end
code[a_, b_, c_] := N[(N[(N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(b * b + N[(c * N[(a * (-3.0)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot \left(-3\right)\right)\right)}}}{a \cdot 3}
\end{array}
Initial program 16.1%
expm1-log1p-u16.1%
expm1-undefine12.9%
Applied egg-rr12.9%
expm1-define16.1%
Simplified16.1%
flip-+16.1%
pow216.1%
add-sqr-sqrt16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
Applied egg-rr16.7%
associate--r-99.5%
Simplified99.5%
*-commutative99.5%
*-commutative99.5%
cancel-sign-sub-inv99.5%
pow299.5%
fma-define99.5%
*-commutative99.5%
Applied egg-rr99.5%
Taylor expanded in b around 0 99.5%
Final simplification99.5%
(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 16.1%
expm1-log1p-u16.1%
expm1-undefine12.9%
Applied egg-rr12.9%
expm1-define16.1%
Simplified16.1%
flip-+16.1%
pow216.1%
add-sqr-sqrt16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
Applied egg-rr16.7%
associate--r-99.5%
Simplified99.5%
Taylor expanded in b around 0 99.5%
+-lft-identity99.5%
*-commutative99.5%
*-commutative99.5%
*-commutative99.5%
Applied egg-rr99.5%
Final simplification99.5%
(FPCore (a b c) :precision binary64 (/ (/ (* 3.0 (* c a)) (- (- b) (sqrt (- (pow b 2.0) (* c (* a 3.0)))))) (* a 3.0)))
double code(double a, double b, double c) {
return ((3.0 * (c * a)) / (-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 * (c * a)) / (-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 * (c * a)) / (-b - Math.sqrt((Math.pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0);
}
def code(a, b, c): return ((3.0 * (c * a)) / (-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(c * a)) / Float64(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 * (c * a)) / (-b - sqrt(((b ^ 2.0) - (c * (a * 3.0)))))) / (a * 3.0); end
code[a_, b_, c_] := N[(N[(N[(3.0 * N[(c * a), $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(c \cdot a\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3}
\end{array}
Initial program 16.1%
expm1-log1p-u16.1%
expm1-undefine12.9%
Applied egg-rr12.9%
expm1-define16.1%
Simplified16.1%
flip-+16.1%
pow216.1%
add-sqr-sqrt16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
pow216.7%
expm1-log1p-u16.7%
*-commutative16.7%
*-commutative16.7%
Applied egg-rr16.7%
associate--r-99.5%
Simplified99.5%
Taylor expanded in b around 0 99.2%
Final simplification99.2%
(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 16.1%
expm1-log1p-u16.1%
expm1-undefine12.9%
Applied egg-rr12.9%
expm1-define16.1%
Simplified16.1%
Taylor expanded in b around inf 96.4%
fma-define96.4%
associate-/l*96.4%
unpow296.4%
unpow296.4%
times-frac96.4%
unpow196.4%
pow-plus96.4%
metadata-eval96.4%
Simplified96.4%
(FPCore (a b c) :precision binary64 (* c (/ 1.0 (* b (- (* 1.5 (/ (* c a) (pow b 2.0))) 2.0)))))
double code(double a, double b, double c) {
return c * (1.0 / (b * ((1.5 * ((c * a) / pow(b, 2.0))) - 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 * (1.0d0 / (b * ((1.5d0 * ((c * a) / (b ** 2.0d0))) - 2.0d0)))
end function
public static double code(double a, double b, double c) {
return c * (1.0 / (b * ((1.5 * ((c * a) / Math.pow(b, 2.0))) - 2.0)));
}
def code(a, b, c): return c * (1.0 / (b * ((1.5 * ((c * a) / math.pow(b, 2.0))) - 2.0)))
function code(a, b, c) return Float64(c * Float64(1.0 / Float64(b * Float64(Float64(1.5 * Float64(Float64(c * a) / (b ^ 2.0))) - 2.0)))) end
function tmp = code(a, b, c) tmp = c * (1.0 / (b * ((1.5 * ((c * a) / (b ^ 2.0))) - 2.0))); end
code[a_, b_, c_] := N[(c * N[(1.0 / N[(b * N[(N[(1.5 * N[(N[(c * a), $MachinePrecision] / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{1}{b \cdot \left(1.5 \cdot \frac{c \cdot a}{{b}^{2}} - 2\right)}
\end{array}
Initial program 16.1%
Simplified16.1%
Taylor expanded in c around 0 96.0%
associate-*r/96.0%
metadata-eval96.0%
Simplified96.0%
Taylor expanded in b around inf 95.9%
clear-num95.9%
inv-pow95.9%
fmm-def95.9%
associate-/l*95.9%
metadata-eval95.9%
Applied egg-rr95.9%
unpow-195.9%
Simplified95.9%
Taylor expanded in b around inf 96.1%
Final simplification96.1%
(FPCore (a b c) :precision binary64 (* c (/ 1.0 (+ (* b -2.0) (* 1.5 (/ (* c a) b))))))
double code(double a, double b, double c) {
return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / 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 * (1.0d0 / ((b * (-2.0d0)) + (1.5d0 * ((c * a) / b))))
end function
public static double code(double a, double b, double c) {
return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b))));
}
def code(a, b, c): return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b))))
function code(a, b, c) return Float64(c * Float64(1.0 / Float64(Float64(b * -2.0) + Float64(1.5 * Float64(Float64(c * a) / b))))) end
function tmp = code(a, b, c) tmp = c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b)))); end
code[a_, b_, c_] := N[(c * N[(1.0 / N[(N[(b * -2.0), $MachinePrecision] + N[(1.5 * N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{1}{b \cdot -2 + 1.5 \cdot \frac{c \cdot a}{b}}
\end{array}
Initial program 16.1%
Simplified16.1%
Taylor expanded in c around 0 96.0%
associate-*r/96.0%
metadata-eval96.0%
Simplified96.0%
Taylor expanded in b around inf 95.9%
clear-num95.9%
inv-pow95.9%
fmm-def95.9%
associate-/l*95.9%
metadata-eval95.9%
Applied egg-rr95.9%
unpow-195.9%
Simplified95.9%
Taylor expanded in a around 0 96.1%
Final simplification96.1%
(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 16.1%
Simplified16.1%
Taylor expanded in b around inf 91.6%
herbie shell --seed 2024154
(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)))