
(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 8 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(Float64(c * a) * -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[(N[(c * a), $MachinePrecision] * -3.0), $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, \left(c \cdot a\right) \cdot -3\right)}}}{a \cdot 3}
\end{array}
Initial program 16.5%
add-sqr-sqrt16.6%
distribute-rgt-neg-in16.6%
Applied egg-rr16.6%
flip-+16.7%
pow216.7%
distribute-rgt-neg-out16.7%
add-sqr-sqrt16.5%
add-sqr-sqrt17.1%
pow217.1%
*-commutative17.1%
*-commutative17.1%
distribute-rgt-neg-out17.1%
add-sqr-sqrt17.1%
Applied egg-rr17.1%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
neg-mul-199.4%
distribute-lft1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fma-neg99.4%
associate-*r*99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in c around 0 99.2%
Taylor expanded in b around 0 99.2%
associate-*r*99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (/ (/ (* 3.0 (* c a)) (- (- b) (sqrt (fma b b (* (* c a) -3.0))))) (* a 3.0)))
double code(double a, double b, double c) {
return ((3.0 * (c * a)) / (-b - sqrt(fma(b, b, ((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(fma(b, b, Float64(Float64(c * a) * -3.0))))) / Float64(a * 3.0)) end
code[a_, b_, c_] := N[(N[(N[(3.0 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(b * b + N[(N[(c * a), $MachinePrecision] * -3.0), $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{\mathsf{fma}\left(b, b, \left(c \cdot a\right) \cdot -3\right)}}}{a \cdot 3}
\end{array}
Initial program 16.5%
add-sqr-sqrt16.6%
distribute-rgt-neg-in16.6%
Applied egg-rr16.6%
flip-+16.7%
pow216.7%
distribute-rgt-neg-out16.7%
add-sqr-sqrt16.5%
add-sqr-sqrt17.1%
pow217.1%
*-commutative17.1%
*-commutative17.1%
distribute-rgt-neg-out17.1%
add-sqr-sqrt17.1%
Applied egg-rr17.1%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
neg-mul-199.4%
distribute-lft1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fma-neg99.4%
associate-*r*99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in c around 0 99.2%
Taylor expanded in b around 0 99.2%
Final simplification99.2%
(FPCore (a b c) :precision binary64 (+ (* -0.5 (/ c b)) (* -0.375 (/ (* a (pow c 2.0)) (pow b 3.0)))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * ((a * pow(c, 2.0)) / 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)) + ((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (-0.5 * (c / b)) + (-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (-0.375 * ((a * (c ^ 2.0)) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}
\end{array}
Initial program 16.5%
Taylor expanded in a around 0 96.7%
(FPCore (a b c) :precision binary64 (/ 1.0 (+ (* -2.0 (/ 1.0 (/ c b))) (* 1.5 (/ a b)))))
double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (1.0 / (c / b))) + (1.5 * (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 = 1.0d0 / (((-2.0d0) * (1.0d0 / (c / b))) + (1.5d0 * (a / b)))
end function
public static double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (1.0 / (c / b))) + (1.5 * (a / b)));
}
def code(a, b, c): return 1.0 / ((-2.0 * (1.0 / (c / b))) + (1.5 * (a / b)))
function code(a, b, c) return Float64(1.0 / Float64(Float64(-2.0 * Float64(1.0 / Float64(c / b))) + Float64(1.5 * Float64(a / b)))) end
function tmp = code(a, b, c) tmp = 1.0 / ((-2.0 * (1.0 / (c / b))) + (1.5 * (a / b))); end
code[a_, b_, c_] := N[(1.0 / N[(N[(-2.0 * N[(1.0 / N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.5 * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{-2 \cdot \frac{1}{\frac{c}{b}} + 1.5 \cdot \frac{a}{b}}
\end{array}
Initial program 16.5%
add-sqr-sqrt16.6%
distribute-rgt-neg-in16.6%
Applied egg-rr16.6%
clear-num16.6%
inv-pow16.6%
*-commutative16.6%
distribute-rgt-neg-out16.6%
add-sqr-sqrt16.5%
pow216.5%
*-commutative16.5%
*-commutative16.5%
Applied egg-rr16.5%
unpow-116.5%
associate-/l*16.5%
+-commutative16.5%
unsub-neg16.5%
unpow216.5%
fma-neg16.6%
associate-*r*16.6%
*-commutative16.6%
distribute-rgt-neg-in16.6%
metadata-eval16.6%
Simplified16.6%
Taylor expanded in a around 0 96.4%
clear-num96.6%
inv-pow96.6%
Applied egg-rr96.6%
unpow-196.6%
Simplified96.6%
(FPCore (a b c) :precision binary64 (/ 1.0 (+ (* 1.5 (/ a b)) (* -2.0 (/ b c)))))
double code(double a, double b, double c) {
return 1.0 / ((1.5 * (a / b)) + (-2.0 * (b / c)));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 1.0d0 / ((1.5d0 * (a / b)) + ((-2.0d0) * (b / c)))
end function
public static double code(double a, double b, double c) {
return 1.0 / ((1.5 * (a / b)) + (-2.0 * (b / c)));
}
def code(a, b, c): return 1.0 / ((1.5 * (a / b)) + (-2.0 * (b / c)))
function code(a, b, c) return Float64(1.0 / Float64(Float64(1.5 * Float64(a / b)) + Float64(-2.0 * Float64(b / c)))) end
function tmp = code(a, b, c) tmp = 1.0 / ((1.5 * (a / b)) + (-2.0 * (b / c))); end
code[a_, b_, c_] := N[(1.0 / N[(N[(1.5 * N[(a / b), $MachinePrecision]), $MachinePrecision] + N[(-2.0 * N[(b / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{1.5 \cdot \frac{a}{b} + -2 \cdot \frac{b}{c}}
\end{array}
Initial program 16.5%
add-sqr-sqrt16.6%
distribute-rgt-neg-in16.6%
Applied egg-rr16.6%
clear-num16.6%
inv-pow16.6%
*-commutative16.6%
distribute-rgt-neg-out16.6%
add-sqr-sqrt16.5%
pow216.5%
*-commutative16.5%
*-commutative16.5%
Applied egg-rr16.5%
unpow-116.5%
associate-/l*16.5%
+-commutative16.5%
unsub-neg16.5%
unpow216.5%
fma-neg16.6%
associate-*r*16.6%
*-commutative16.6%
distribute-rgt-neg-in16.6%
metadata-eval16.6%
Simplified16.6%
Taylor expanded in a around 0 96.4%
Final simplification96.4%
(FPCore (a b c) :precision binary64 (/ (* c -0.5) b))
double code(double a, double b, double c) {
return (c * -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 * (-0.5d0)) / b
end function
public static double code(double a, double b, double c) {
return (c * -0.5) / b;
}
def code(a, b, c): return (c * -0.5) / b
function code(a, b, c) return Float64(Float64(c * -0.5) / b) end
function tmp = code(a, b, c) tmp = (c * -0.5) / b; end
code[a_, b_, c_] := N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot -0.5}{b}
\end{array}
Initial program 16.5%
Taylor expanded in b around inf 91.7%
associate-*r/91.7%
*-commutative91.7%
Simplified91.7%
(FPCore (a b c) :precision binary64 (* c (/ -0.5 b)))
double code(double a, double b, double c) {
return c * (-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 * ((-0.5d0) / b)
end function
public static double code(double a, double b, double c) {
return c * (-0.5 / b);
}
def code(a, b, c): return c * (-0.5 / b)
function code(a, b, c) return Float64(c * Float64(-0.5 / b)) end
function tmp = code(a, b, c) tmp = c * (-0.5 / b); end
code[a_, b_, c_] := N[(c * N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{-0.5}{b}
\end{array}
Initial program 16.5%
Taylor expanded in b around inf 91.7%
associate-*r/91.7%
*-commutative91.7%
Simplified91.7%
Taylor expanded in c around 0 91.7%
associate-*r/91.7%
*-commutative91.7%
associate-*r/91.4%
Simplified91.4%
(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 16.5%
add-sqr-sqrt16.6%
distribute-rgt-neg-in16.6%
Applied egg-rr16.6%
Taylor expanded in a around 0 3.3%
associate-*r/3.3%
distribute-rgt1-in3.3%
metadata-eval3.3%
mul0-lft3.3%
metadata-eval3.3%
Simplified3.3%
Taylor expanded in a around 0 3.3%
herbie shell --seed 2024114
(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)))