
(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 (/ (* (/ (* a c) a) 2.0) (- (- b) (sqrt (* c (fma a -4.0 (/ (pow b 2.0) c)))))))
double code(double a, double b, double c) {
return (((a * c) / a) * 2.0) / (-b - sqrt((c * fma(a, -4.0, (pow(b, 2.0) / c)))));
}
function code(a, b, c) return Float64(Float64(Float64(Float64(a * c) / a) * 2.0) / Float64(Float64(-b) - sqrt(Float64(c * fma(a, -4.0, Float64((b ^ 2.0) / c)))))) end
code[a_, b_, c_] := N[(N[(N[(N[(a * c), $MachinePrecision] / a), $MachinePrecision] * 2.0), $MachinePrecision] / N[((-b) - N[Sqrt[N[(c * N[(a * -4.0 + N[(N[Power[b, 2.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{a \cdot c}{a} \cdot 2}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -4, \frac{{b}^{2}}{c}\right)}}
\end{array}
Initial program 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in c around inf 15.0%
flip-+15.2%
pow215.2%
add-sqr-sqrt15.8%
cancel-sign-sub-inv15.8%
metadata-eval15.8%
cancel-sign-sub-inv15.8%
metadata-eval15.8%
Applied egg-rr15.8%
Taylor expanded in b around 0 99.3%
*-commutative99.3%
*-commutative99.3%
Simplified99.3%
*-un-lft-identity99.3%
associate-/l/99.4%
associate-*l*99.4%
+-commutative99.4%
*-commutative99.4%
fma-define99.4%
Applied egg-rr99.4%
*-lft-identity99.4%
associate-/r*99.7%
associate-*r*99.7%
times-frac99.7%
*-commutative99.7%
metadata-eval99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (a b c) :precision binary64 (/ (/ (* (* a c) 4.0) (- (- b) (sqrt (+ (pow b 2.0) (* (* a c) -4.0))))) (* a 2.0)))
double code(double a, double b, double c) {
return (((a * c) * 4.0) / (-b - sqrt((pow(b, 2.0) + ((a * c) * -4.0))))) / (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
code = (((a * c) * 4.0d0) / (-b - sqrt(((b ** 2.0d0) + ((a * c) * (-4.0d0)))))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return (((a * c) * 4.0) / (-b - Math.sqrt((Math.pow(b, 2.0) + ((a * c) * -4.0))))) / (a * 2.0);
}
def code(a, b, c): return (((a * c) * 4.0) / (-b - math.sqrt((math.pow(b, 2.0) + ((a * c) * -4.0))))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(Float64(a * c) * 4.0) / Float64(Float64(-b) - sqrt(Float64((b ^ 2.0) + Float64(Float64(a * c) * -4.0))))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = (((a * c) * 4.0) / (-b - sqrt(((b ^ 2.0) + ((a * c) * -4.0))))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(N[(a * c), $MachinePrecision] * 4.0), $MachinePrecision] / N[((-b) - N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] + N[(N[(a * c), $MachinePrecision] * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\left(a \cdot c\right) \cdot 4}{\left(-b\right) - \sqrt{{b}^{2} + \left(a \cdot c\right) \cdot -4}}}{a \cdot 2}
\end{array}
Initial program 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in c around inf 15.0%
flip-+15.2%
pow215.2%
add-sqr-sqrt15.8%
cancel-sign-sub-inv15.8%
metadata-eval15.8%
cancel-sign-sub-inv15.8%
metadata-eval15.8%
Applied egg-rr15.8%
Taylor expanded in b around 0 99.3%
*-commutative99.3%
*-commutative99.3%
Simplified99.3%
Taylor expanded in c around 0 99.3%
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 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in a around 0 96.8%
mul-1-neg96.8%
unsub-neg96.8%
associate-*r/96.8%
mul-1-neg96.8%
associate-/l*96.8%
Simplified96.8%
Final simplification96.8%
(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 / 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 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in c around 0 96.5%
associate-*r/96.5%
neg-mul-196.5%
distribute-rgt-neg-in96.5%
Simplified96.5%
Taylor expanded in c around inf 96.2%
mul-1-neg96.2%
*-commutative96.2%
Simplified96.2%
Taylor expanded in b around inf 96.8%
distribute-lft-out96.8%
associate-*r/96.8%
mul-1-neg96.8%
distribute-neg-frac296.8%
associate-/l*96.8%
unpow296.8%
unpow296.8%
times-frac96.8%
unpow296.8%
Simplified96.8%
Final simplification96.8%
(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(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 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in b around inf 92.4%
associate-*r/92.4%
mul-1-neg92.4%
Simplified92.4%
Final simplification92.4%
(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 15.2%
*-commutative15.2%
Simplified15.2%
Taylor expanded in c around inf 15.0%
div-inv15.1%
neg-mul-115.1%
fma-define15.1%
cancel-sign-sub-inv15.1%
metadata-eval15.1%
Applied egg-rr15.1%
Taylor expanded in c around 0 3.3%
associate-*r/3.3%
distribute-rgt1-in3.3%
metadata-eval3.3%
mul0-lft3.3%
metadata-eval3.3%
Simplified3.3%
Final simplification3.3%
herbie shell --seed 2024080
(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)))