
(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 28.0%
*-commutative28.0%
Simplified28.0%
neg-sub028.0%
flip--28.3%
metadata-eval28.3%
pow228.3%
add-sqr-sqrt28.1%
sqrt-prod28.3%
sqr-neg28.3%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod28.3%
sqr-neg28.3%
sqrt-prod28.1%
add-sqr-sqrt28.3%
Applied egg-rr28.3%
neg-sub028.3%
Simplified28.3%
flip-+28.3%
Applied egg-rr28.7%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
+-commutative99.4%
neg-mul-199.4%
distribute-rgt1-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 (/ (- (* a (- (pow (/ c (- b)) 2.0))) c) b))
double code(double a, double b, double c) {
return ((a * -pow((c / -b), 2.0)) - 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 = ((a * -((c / -b) ** 2.0d0)) - c) / b
end function
public static double code(double a, double b, double c) {
return ((a * -Math.pow((c / -b), 2.0)) - c) / b;
}
def code(a, b, c): return ((a * -math.pow((c / -b), 2.0)) - c) / b
function code(a, b, c) return Float64(Float64(Float64(a * Float64(-(Float64(c / Float64(-b)) ^ 2.0))) - c) / b) end
function tmp = code(a, b, c) tmp = ((a * -((c / -b) ^ 2.0)) - c) / b; end
code[a_, b_, c_] := N[(N[(N[(a * (-N[Power[N[(c / (-b)), $MachinePrecision], 2.0], $MachinePrecision])), $MachinePrecision] - c), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{a \cdot \left(-{\left(\frac{c}{-b}\right)}^{2}\right) - c}{b}
\end{array}
Initial program 28.0%
*-commutative28.0%
Simplified28.1%
Taylor expanded in c around 0 92.2%
associate-*r/92.2%
neg-mul-192.2%
distribute-rgt-neg-in92.2%
Simplified92.2%
Taylor expanded in b around inf 92.5%
neg-mul-192.5%
+-commutative92.5%
unsub-neg92.5%
mul-1-neg92.5%
associate-/l*92.5%
distribute-lft-neg-in92.5%
unpow292.5%
unpow292.5%
times-frac92.5%
sqr-neg92.5%
unpow292.5%
distribute-neg-frac292.5%
Simplified92.5%
Final simplification92.5%
(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 28.0%
*-commutative28.0%
Simplified28.0%
neg-sub028.0%
flip--28.3%
metadata-eval28.3%
pow228.3%
add-sqr-sqrt28.1%
sqrt-prod28.3%
sqr-neg28.3%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod28.3%
sqr-neg28.3%
sqrt-prod28.1%
add-sqr-sqrt28.3%
Applied egg-rr28.3%
neg-sub028.3%
Simplified28.3%
flip-+28.3%
Applied egg-rr28.7%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
+-commutative99.4%
neg-mul-199.4%
distribute-rgt1-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%
Taylor expanded in a around 0 92.4%
distribute-lft-out--92.4%
*-commutative92.4%
Simplified92.4%
(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 28.0%
*-commutative28.0%
Simplified28.1%
Taylor expanded in b around inf 83.9%
associate-*r/83.9%
mul-1-neg83.9%
Simplified83.9%
Final simplification83.9%
(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 28.0%
*-commutative28.0%
Simplified28.0%
neg-sub028.0%
flip--28.3%
metadata-eval28.3%
pow228.3%
add-sqr-sqrt28.1%
sqrt-prod28.3%
sqr-neg28.3%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod28.3%
sqr-neg28.3%
sqrt-prod28.1%
add-sqr-sqrt28.3%
Applied egg-rr28.3%
neg-sub028.3%
Simplified28.3%
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 2024185
(FPCore (a b c)
:name "Quadratic roots, 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) (* (* 4.0 a) c)))) (* 2.0 a)))