
(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 6 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 (/ (/ (- (* 0.0 (+ b b)) (* c (* a 4.0))) (+ b (sqrt (fma b b (* (* c a) -4.0))))) (* a 2.0)))
double code(double a, double b, double c) {
return (((0.0 * (b + b)) - (c * (a * 4.0))) / (b + sqrt(fma(b, b, ((c * a) * -4.0))))) / (a * 2.0);
}
function code(a, b, c) return Float64(Float64(Float64(Float64(0.0 * Float64(b + b)) - Float64(c * Float64(a * 4.0))) / Float64(b + sqrt(fma(b, b, Float64(Float64(c * a) * -4.0))))) / Float64(a * 2.0)) end
code[a_, b_, c_] := N[(N[(N[(N[(0.0 * N[(b + b), $MachinePrecision]), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $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{0 \cdot \left(b + b\right) - c \cdot \left(a \cdot 4\right)}{b + \sqrt{\mathsf{fma}\left(b, b, \left(c \cdot a\right) \cdot -4\right)}}}{a \cdot 2}
\end{array}
Initial program 18.5%
*-commutative18.5%
Simplified18.5%
neg-sub018.5%
flip3--18.5%
metadata-eval18.5%
metadata-eval18.5%
pow218.5%
Applied egg-rr18.5%
sub0-neg18.5%
+-lft-identity18.5%
mul0-lft18.5%
+-rgt-identity18.5%
Simplified18.5%
flip-+18.5%
Applied egg-rr19.2%
associate--r-99.3%
unpow299.3%
unpow299.3%
difference-of-squares99.3%
+-commutative99.3%
neg-mul-199.3%
distribute-rgt1-in99.3%
metadata-eval99.3%
mul0-lft99.3%
unpow299.3%
fma-neg99.3%
associate-*r*99.3%
*-commutative99.3%
distribute-rgt-neg-in99.3%
metadata-eval99.3%
Simplified99.3%
Final simplification99.3%
(FPCore (a b c) :precision binary64 (- (/ c (- b)) (* a (/ (pow c 2.0) (pow b 3.0)))))
double code(double a, double b, double c) {
return (c / -b) - (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 = (c / -b) - (a * ((c ** 2.0d0) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (c / -b) - (a * (Math.pow(c, 2.0) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (c / -b) - (a * (math.pow(c, 2.0) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(c / Float64(-b)) - Float64(a * Float64((c ^ 2.0) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (c / -b) - (a * ((c ^ 2.0) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(c / (-b)), $MachinePrecision] - N[(a * N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{c}{-b} - a \cdot \frac{{c}^{2}}{{b}^{3}}
\end{array}
Initial program 18.5%
*-commutative18.5%
Simplified18.5%
Taylor expanded in a around 0 94.5%
mul-1-neg94.5%
unsub-neg94.5%
mul-1-neg94.5%
distribute-neg-frac294.5%
associate-/l*94.5%
Simplified94.5%
(FPCore (a b c) :precision binary64 (/ (- (* (pow (/ c b) 2.0) (- a)) c) b))
double code(double a, double b, double c) {
return ((pow((c / b), 2.0) * -a) - 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) ** 2.0d0) * -a) - c) / b
end function
public static double code(double a, double b, double c) {
return ((Math.pow((c / b), 2.0) * -a) - c) / b;
}
def code(a, b, c): return ((math.pow((c / b), 2.0) * -a) - c) / b
function code(a, b, c) return Float64(Float64(Float64((Float64(c / b) ^ 2.0) * Float64(-a)) - c) / b) end
function tmp = code(a, b, c) tmp = ((((c / b) ^ 2.0) * -a) - c) / b; end
code[a_, b_, c_] := N[(N[(N[(N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision] * (-a)), $MachinePrecision] - c), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(\frac{c}{b}\right)}^{2} \cdot \left(-a\right) - c}{b}
\end{array}
Initial program 18.5%
*-commutative18.5%
Simplified18.5%
Taylor expanded in a around 0 97.1%
+-commutative97.1%
mul-1-neg97.1%
unsub-neg97.1%
Simplified97.1%
Taylor expanded in c around 0 97.1%
Taylor expanded in b around inf 94.4%
mul-1-neg94.4%
associate-/l*94.4%
unpow294.4%
unpow294.4%
times-frac94.4%
unpow294.4%
Simplified94.4%
Final simplification94.4%
(FPCore (a b c) :precision binary64 (* c (/ (- -1.0 (* a (/ c (* b b)))) b)))
double code(double a, double b, double c) {
return c * ((-1.0 - (a * (c / (b * b)))) / 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) - (a * (c / (b * b)))) / b)
end function
public static double code(double a, double b, double c) {
return c * ((-1.0 - (a * (c / (b * b)))) / b);
}
def code(a, b, c): return c * ((-1.0 - (a * (c / (b * b)))) / b)
function code(a, b, c) return Float64(c * Float64(Float64(-1.0 - Float64(a * Float64(c / Float64(b * b)))) / b)) end
function tmp = code(a, b, c) tmp = c * ((-1.0 - (a * (c / (b * b)))) / b); end
code[a_, b_, c_] := N[(c * N[(N[(-1.0 - N[(a * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{-1 - a \cdot \frac{c}{b \cdot b}}{b}
\end{array}
Initial program 18.5%
*-commutative18.5%
Simplified18.5%
Taylor expanded in c around 0 94.1%
associate-*r/94.1%
neg-mul-194.1%
distribute-rgt-neg-in94.1%
Simplified94.1%
Taylor expanded in b around -inf 94.1%
associate-*r/94.1%
mul-1-neg94.1%
associate-/l*94.1%
Simplified94.1%
unpow294.1%
Applied egg-rr94.1%
Final simplification94.1%
(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 18.5%
*-commutative18.5%
Simplified18.5%
Taylor expanded in a around 0 89.7%
associate-*r/89.7%
mul-1-neg89.7%
Simplified89.7%
Final simplification89.7%
(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 18.5%
*-commutative18.5%
Simplified18.5%
neg-sub018.5%
flip3--18.5%
metadata-eval18.5%
metadata-eval18.5%
pow218.5%
Applied egg-rr18.5%
sub0-neg18.5%
+-lft-identity18.5%
mul0-lft18.5%
+-rgt-identity18.5%
Simplified18.5%
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 2024136
(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)))