
(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 5 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 (/ (/ (* 4.0 (* c a)) (- (- b) (sqrt (fma b b (* (* c a) -4.0))))) (* a 2.0)))
double code(double a, double b, double c) {
return ((4.0 * (c * a)) / (-b - sqrt(fma(b, b, ((c * a) * -4.0))))) / (a * 2.0);
}
function code(a, b, c) return Float64(Float64(Float64(4.0 * Float64(c * a)) / Float64(Float64(-b) - sqrt(fma(b, b, Float64(Float64(c * a) * -4.0))))) / Float64(a * 2.0)) end
code[a_, b_, c_] := N[(N[(N[(4.0 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(b * b + N[(N[(c * a), $MachinePrecision] * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{4 \cdot \left(c \cdot a\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, \left(c \cdot a\right) \cdot -4\right)}}}{a \cdot 2}
\end{array}
Initial program 16.9%
*-commutative16.9%
Simplified16.9%
add-cbrt-cube17.5%
cbrt-prod17.8%
distribute-rgt-neg-in17.8%
cbrt-prod18.1%
pow218.1%
Applied egg-rr18.1%
flip-+18.2%
pow218.2%
distribute-rgt-neg-out18.2%
unpow218.2%
add-cube-cbrt17.1%
add-sqr-sqrt17.4%
pow217.4%
associate-*l*17.4%
Applied egg-rr17.4%
associate--r-99.4%
unpow299.2%
unpow299.4%
difference-of-squares99.4%
neg-mul-199.4%
distribute-lft1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fmm-def99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
*-commutative99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (/ (+ c (* a (pow (/ c (- b)) 2.0))) (- b)))
double code(double a, double b, double c) {
return (c + (a * pow((c / -b), 2.0))) / -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 + (a * ((c / -b) ** 2.0d0))) / -b
end function
public static double code(double a, double b, double c) {
return (c + (a * Math.pow((c / -b), 2.0))) / -b;
}
def code(a, b, c): return (c + (a * math.pow((c / -b), 2.0))) / -b
function code(a, b, c) return Float64(Float64(c + Float64(a * (Float64(c / Float64(-b)) ^ 2.0))) / Float64(-b)) end
function tmp = code(a, b, c) tmp = (c + (a * ((c / -b) ^ 2.0))) / -b; end
code[a_, b_, c_] := N[(N[(c + N[(a * N[Power[N[(c / (-b)), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / (-b)), $MachinePrecision]
\begin{array}{l}
\\
\frac{c + a \cdot {\left(\frac{c}{-b}\right)}^{2}}{-b}
\end{array}
Initial program 16.9%
*-commutative16.9%
Simplified16.9%
Taylor expanded in c around 0 95.4%
associate-*r/95.4%
neg-mul-195.4%
distribute-rgt-neg-in95.4%
Simplified95.4%
Taylor expanded in b around inf 95.7%
distribute-lft-out95.7%
associate-*r/95.7%
mul-1-neg95.7%
distribute-neg-frac295.7%
+-commutative95.7%
associate-/l*95.7%
fma-define95.7%
unpow295.7%
unpow295.7%
times-frac95.7%
sqr-neg95.7%
unpow195.7%
pow-plus95.7%
distribute-neg-frac95.7%
metadata-eval95.7%
Simplified95.7%
fma-undefine95.7%
Applied egg-rr95.7%
Final simplification95.7%
(FPCore (a b c) :precision binary64 (/ (/ (* 4.0 (* c a)) (* 2.0 (- (/ (* c a) b) b))) (* a 2.0)))
double code(double a, double b, double c) {
return ((4.0 * (c * a)) / (2.0 * (((c * a) / b) - b))) / (a * 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 = ((4.0d0 * (c * a)) / (2.0d0 * (((c * a) / b) - b))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return ((4.0 * (c * a)) / (2.0 * (((c * a) / b) - b))) / (a * 2.0);
}
def code(a, b, c): return ((4.0 * (c * a)) / (2.0 * (((c * a) / b) - b))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(4.0 * Float64(c * a)) / Float64(2.0 * Float64(Float64(Float64(c * a) / b) - b))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = ((4.0 * (c * a)) / (2.0 * (((c * a) / b) - b))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(4.0 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[(2.0 * N[(N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{4 \cdot \left(c \cdot a\right)}{2 \cdot \left(\frac{c \cdot a}{b} - b\right)}}{a \cdot 2}
\end{array}
Initial program 16.9%
*-commutative16.9%
Simplified16.9%
add-cbrt-cube17.5%
cbrt-prod17.8%
distribute-rgt-neg-in17.8%
cbrt-prod18.1%
pow218.1%
Applied egg-rr18.1%
flip-+18.2%
pow218.2%
distribute-rgt-neg-out18.2%
unpow218.2%
add-cube-cbrt17.1%
add-sqr-sqrt17.4%
pow217.4%
associate-*l*17.4%
Applied egg-rr17.4%
associate--r-99.4%
unpow299.2%
unpow299.4%
difference-of-squares99.4%
neg-mul-199.4%
distribute-lft1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fmm-def99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in a around 0 95.5%
distribute-lft-out--95.5%
*-commutative95.5%
Simplified95.5%
Taylor expanded in b around 0 95.5%
*-commutative99.4%
Simplified95.5%
(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(c / Float64(-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 16.9%
*-commutative16.9%
Simplified16.9%
Taylor expanded in b around inf 91.2%
associate-*r/91.2%
mul-1-neg91.2%
Simplified91.2%
Final simplification91.2%
(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 16.9%
*-commutative16.9%
Simplified16.9%
add-cbrt-cube17.5%
cbrt-prod17.8%
distribute-rgt-neg-in17.8%
cbrt-prod18.1%
pow218.1%
Applied egg-rr18.1%
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%
herbie shell --seed 2024170
(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)))