
(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 (let* ((t_0 (* c (* 4.0 a)))) (/ (/ t_0 (- (- b) (sqrt (- (pow b 2.0) t_0)))) (* a 2.0))))
double code(double a, double b, double c) {
double t_0 = c * (4.0 * a);
return (t_0 / (-b - sqrt((pow(b, 2.0) - t_0)))) / (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
real(8) :: t_0
t_0 = c * (4.0d0 * a)
code = (t_0 / (-b - sqrt(((b ** 2.0d0) - t_0)))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
double t_0 = c * (4.0 * a);
return (t_0 / (-b - Math.sqrt((Math.pow(b, 2.0) - t_0)))) / (a * 2.0);
}
def code(a, b, c): t_0 = c * (4.0 * a) return (t_0 / (-b - math.sqrt((math.pow(b, 2.0) - t_0)))) / (a * 2.0)
function code(a, b, c) t_0 = Float64(c * Float64(4.0 * a)) return Float64(Float64(t_0 / Float64(Float64(-b) - sqrt(Float64((b ^ 2.0) - t_0)))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) t_0 = c * (4.0 * a); tmp = (t_0 / (-b - sqrt(((b ^ 2.0) - t_0)))) / (a * 2.0); end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(4.0 * a), $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 * 2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := c \cdot \left(4 \cdot a\right)\\
\frac{\frac{t\_0}{\left(-b\right) - \sqrt{{b}^{2} - t\_0}}}{a \cdot 2}
\end{array}
\end{array}
Initial program 30.7%
*-commutative30.7%
Simplified30.7%
add-sqr-sqrt30.8%
distribute-rgt-neg-in30.8%
Applied egg-rr30.8%
flip-+31.0%
pow231.0%
distribute-rgt-neg-out31.0%
add-sqr-sqrt30.8%
add-sqr-sqrt31.6%
pow231.6%
*-commutative31.6%
distribute-rgt-neg-out31.6%
add-sqr-sqrt31.6%
pow231.6%
*-commutative31.6%
Applied egg-rr31.6%
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%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
*-commutative99.4%
*-commutative99.4%
associate-*r*99.4%
*-commutative99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (if (<= b 9e-6) (/ (- (sqrt (- (* b b) (* c (* 4.0 a)))) b) (* a 2.0)) (/ (- (- c) (* a (pow (- (/ c b)) 2.0))) b)))
double code(double a, double b, double c) {
double tmp;
if (b <= 9e-6) {
tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0);
} else {
tmp = (-c - (a * pow(-(c / b), 2.0))) / b;
}
return tmp;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8) :: tmp
if (b <= 9d-6) then
tmp = (sqrt(((b * b) - (c * (4.0d0 * a)))) - b) / (a * 2.0d0)
else
tmp = (-c - (a * (-(c / b) ** 2.0d0))) / b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 9e-6) {
tmp = (Math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0);
} else {
tmp = (-c - (a * Math.pow(-(c / b), 2.0))) / b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 9e-6: tmp = (math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0) else: tmp = (-c - (a * math.pow(-(c / b), 2.0))) / b return tmp
function code(a, b, c) tmp = 0.0 if (b <= 9e-6) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) - b) / Float64(a * 2.0)); else tmp = Float64(Float64(Float64(-c) - Float64(a * (Float64(-Float64(c / b)) ^ 2.0))) / b); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 9e-6) tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0); else tmp = (-c - (a * (-(c / b) ^ 2.0))) / b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 9e-6], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[((-c) - N[(a * N[Power[(-N[(c / b), $MachinePrecision]), 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 9 \cdot 10^{-6}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{\left(-c\right) - a \cdot {\left(-\frac{c}{b}\right)}^{2}}{b}\\
\end{array}
\end{array}
if b < 9.00000000000000023e-6Initial program 85.3%
if 9.00000000000000023e-6 < b Initial program 27.5%
*-commutative27.5%
Simplified27.5%
Taylor expanded in a around 0 97.1%
Taylor expanded in c around inf 97.1%
Taylor expanded in b around inf 92.8%
mul-1-neg92.8%
unsub-neg92.8%
mul-1-neg92.8%
associate-/l*92.8%
unpow292.8%
unpow292.8%
times-frac92.8%
sqr-neg92.8%
unpow292.8%
distribute-neg-frac292.8%
Simplified92.8%
Final simplification92.4%
(FPCore (a b c) :precision binary64 (/ (/ (+ (* c (* 4.0 a)) (* 0.0 (+ b b))) (* 2.0 (- (* a (/ c b)) b))) (* a 2.0)))
double code(double a, double b, double c) {
return (((c * (4.0 * a)) + (0.0 * (b + b))) / (2.0 * ((a * (c / 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 = (((c * (4.0d0 * a)) + (0.0d0 * (b + b))) / (2.0d0 * ((a * (c / b)) - b))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return (((c * (4.0 * a)) + (0.0 * (b + b))) / (2.0 * ((a * (c / b)) - b))) / (a * 2.0);
}
def code(a, b, c): return (((c * (4.0 * a)) + (0.0 * (b + b))) / (2.0 * ((a * (c / b)) - b))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(Float64(c * Float64(4.0 * a)) + Float64(0.0 * Float64(b + b))) / Float64(2.0 * Float64(Float64(a * Float64(c / b)) - b))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = (((c * (4.0 * a)) + (0.0 * (b + b))) / (2.0 * ((a * (c / b)) - b))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision] + N[(0.0 * N[(b + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(2.0 * N[(N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(4 \cdot a\right) + 0 \cdot \left(b + b\right)}{2 \cdot \left(a \cdot \frac{c}{b} - b\right)}}{a \cdot 2}
\end{array}
Initial program 30.7%
*-commutative30.7%
Simplified30.7%
add-sqr-sqrt30.8%
distribute-rgt-neg-in30.8%
Applied egg-rr30.8%
flip-+31.0%
pow231.0%
distribute-rgt-neg-out31.0%
add-sqr-sqrt30.8%
add-sqr-sqrt31.6%
pow231.6%
*-commutative31.6%
distribute-rgt-neg-out31.6%
add-sqr-sqrt31.6%
pow231.6%
*-commutative31.6%
Applied egg-rr31.6%
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%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in c around 0 90.8%
distribute-lft-out--90.8%
associate-*r/90.8%
Simplified90.8%
Final simplification90.8%
(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(-Float64(c / 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 30.7%
*-commutative30.7%
Simplified30.6%
Taylor expanded in b around inf 81.7%
associate-*r/81.7%
mul-1-neg81.7%
Simplified81.7%
Final simplification81.7%
(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 30.7%
*-commutative30.7%
Simplified30.7%
add-sqr-sqrt30.8%
distribute-rgt-neg-in30.8%
Applied egg-rr30.8%
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 2024177
(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)))