
(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 8 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
(/
(fma
-2.0
(* (pow a 2.0) (/ (pow c 3.0) (pow b 4.0)))
(-
(-
(/ (* -5.0 (pow (* a c) 4.0)) (* a (pow b 6.0)))
(/ (* a (pow c 2.0)) (pow b 2.0)))
c))
b))
double code(double a, double b, double c) {
return fma(-2.0, (pow(a, 2.0) * (pow(c, 3.0) / pow(b, 4.0))), ((((-5.0 * pow((a * c), 4.0)) / (a * pow(b, 6.0))) - ((a * pow(c, 2.0)) / pow(b, 2.0))) - c)) / b;
}
function code(a, b, c) return Float64(fma(-2.0, Float64((a ^ 2.0) * Float64((c ^ 3.0) / (b ^ 4.0))), Float64(Float64(Float64(Float64(-5.0 * (Float64(a * c) ^ 4.0)) / Float64(a * (b ^ 6.0))) - Float64(Float64(a * (c ^ 2.0)) / (b ^ 2.0))) - c)) / b) end
code[a_, b_, c_] := N[(N[(-2.0 * N[(N[Power[a, 2.0], $MachinePrecision] * N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(-5.0 * N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision]), $MachinePrecision] / N[(a * N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - c), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-2, {a}^{2} \cdot \frac{{c}^{3}}{{b}^{4}}, \left(\frac{-5 \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{6}} - \frac{a \cdot {c}^{2}}{{b}^{2}}\right) - c\right)}{b}
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in b around inf 98.6%
Simplified98.6%
frac-times98.6%
associate-*r*98.6%
pow-prod-down98.6%
*-commutative98.6%
Applied egg-rr98.6%
*-commutative98.6%
associate-*r*98.6%
metadata-eval98.6%
Simplified98.6%
Final simplification98.6%
(FPCore (a b c)
:precision binary64
(-
(*
a
(-
(*
a
(+
(* -2.0 (/ (pow c 3.0) (pow b 5.0)))
(* -0.25 (* a (/ (* (pow c 4.0) 20.0) (pow b 7.0))))))
(/ (pow c 2.0) (pow b 3.0))))
(/ c b)))
double code(double a, double b, double c) {
return (a * ((a * ((-2.0 * (pow(c, 3.0) / pow(b, 5.0))) + (-0.25 * (a * ((pow(c, 4.0) * 20.0) / pow(b, 7.0)))))) - (pow(c, 2.0) / pow(b, 3.0)))) - (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 * ((a * (((-2.0d0) * ((c ** 3.0d0) / (b ** 5.0d0))) + ((-0.25d0) * (a * (((c ** 4.0d0) * 20.0d0) / (b ** 7.0d0)))))) - ((c ** 2.0d0) / (b ** 3.0d0)))) - (c / b)
end function
public static double code(double a, double b, double c) {
return (a * ((a * ((-2.0 * (Math.pow(c, 3.0) / Math.pow(b, 5.0))) + (-0.25 * (a * ((Math.pow(c, 4.0) * 20.0) / Math.pow(b, 7.0)))))) - (Math.pow(c, 2.0) / Math.pow(b, 3.0)))) - (c / b);
}
def code(a, b, c): return (a * ((a * ((-2.0 * (math.pow(c, 3.0) / math.pow(b, 5.0))) + (-0.25 * (a * ((math.pow(c, 4.0) * 20.0) / math.pow(b, 7.0)))))) - (math.pow(c, 2.0) / math.pow(b, 3.0)))) - (c / b)
function code(a, b, c) return Float64(Float64(a * Float64(Float64(a * Float64(Float64(-2.0 * Float64((c ^ 3.0) / (b ^ 5.0))) + Float64(-0.25 * Float64(a * Float64(Float64((c ^ 4.0) * 20.0) / (b ^ 7.0)))))) - Float64((c ^ 2.0) / (b ^ 3.0)))) - Float64(c / b)) end
function tmp = code(a, b, c) tmp = (a * ((a * ((-2.0 * ((c ^ 3.0) / (b ^ 5.0))) + (-0.25 * (a * (((c ^ 4.0) * 20.0) / (b ^ 7.0)))))) - ((c ^ 2.0) / (b ^ 3.0)))) - (c / b); end
code[a_, b_, c_] := N[(N[(a * N[(N[(a * N[(N[(-2.0 * N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.25 * N[(a * N[(N[(N[Power[c, 4.0], $MachinePrecision] * 20.0), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot \left(a \cdot \left(-2 \cdot \frac{{c}^{3}}{{b}^{5}} + -0.25 \cdot \left(a \cdot \frac{{c}^{4} \cdot 20}{{b}^{7}}\right)\right) - \frac{{c}^{2}}{{b}^{3}}\right) - \frac{c}{b}
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in a around 0 98.6%
Taylor expanded in b around 0 98.6%
associate-/l*98.6%
distribute-rgt-out98.6%
metadata-eval98.6%
Simplified98.6%
Final simplification98.6%
(FPCore (a b c) :precision binary64 (- (* a (- (* -2.0 (/ (* a (pow c 3.0)) (pow b 5.0))) (/ (pow c 2.0) (pow b 3.0)))) (/ c b)))
double code(double a, double b, double c) {
return (a * ((-2.0 * ((a * pow(c, 3.0)) / pow(b, 5.0))) - (pow(c, 2.0) / pow(b, 3.0)))) - (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 * (((-2.0d0) * ((a * (c ** 3.0d0)) / (b ** 5.0d0))) - ((c ** 2.0d0) / (b ** 3.0d0)))) - (c / b)
end function
public static double code(double a, double b, double c) {
return (a * ((-2.0 * ((a * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) - (Math.pow(c, 2.0) / Math.pow(b, 3.0)))) - (c / b);
}
def code(a, b, c): return (a * ((-2.0 * ((a * math.pow(c, 3.0)) / math.pow(b, 5.0))) - (math.pow(c, 2.0) / math.pow(b, 3.0)))) - (c / b)
function code(a, b, c) return Float64(Float64(a * Float64(Float64(-2.0 * Float64(Float64(a * (c ^ 3.0)) / (b ^ 5.0))) - Float64((c ^ 2.0) / (b ^ 3.0)))) - Float64(c / b)) end
function tmp = code(a, b, c) tmp = (a * ((-2.0 * ((a * (c ^ 3.0)) / (b ^ 5.0))) - ((c ^ 2.0) / (b ^ 3.0)))) - (c / b); end
code[a_, b_, c_] := N[(N[(a * N[(N[(-2.0 * N[(N[(a * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot \left(-2 \cdot \frac{a \cdot {c}^{3}}{{b}^{5}} - \frac{{c}^{2}}{{b}^{3}}\right) - \frac{c}{b}
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in a around 0 97.8%
Final simplification97.8%
(FPCore (a b c) :precision binary64 (* c (- (/ -1.0 b) (/ (fma 2.0 (pow (/ (* a c) b) 2.0) (* a c)) (pow b 3.0)))))
double code(double a, double b, double c) {
return c * ((-1.0 / b) - (fma(2.0, pow(((a * c) / b), 2.0), (a * c)) / pow(b, 3.0)));
}
function code(a, b, c) return Float64(c * Float64(Float64(-1.0 / b) - Float64(fma(2.0, (Float64(Float64(a * c) / b) ^ 2.0), Float64(a * c)) / (b ^ 3.0)))) end
code[a_, b_, c_] := N[(c * N[(N[(-1.0 / b), $MachinePrecision] - N[(N[(2.0 * N[Power[N[(N[(a * c), $MachinePrecision] / b), $MachinePrecision], 2.0], $MachinePrecision] + N[(a * c), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(\frac{-1}{b} - \frac{\mathsf{fma}\left(2, {\left(\frac{a \cdot c}{b}\right)}^{2}, a \cdot c\right)}{{b}^{3}}\right)
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in c around 0 97.4%
Taylor expanded in b around -inf 97.4%
mul-1-neg97.4%
distribute-neg-frac297.4%
fma-define97.4%
associate-/l*97.4%
unpow297.4%
unpow297.4%
unpow297.4%
times-frac97.4%
swap-sqr97.4%
unpow197.4%
pow-plus97.4%
associate-*r/97.4%
metadata-eval97.4%
Simplified97.4%
Final simplification97.4%
(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(Float64(-c) / 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 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in a around 0 96.6%
mul-1-neg96.6%
unsub-neg96.6%
mul-1-neg96.6%
distribute-neg-frac296.6%
associate-/l*96.6%
Simplified96.6%
Final simplification96.6%
(FPCore (a b c) :precision binary64 (/ (fma a (pow (/ c (- b)) 2.0) c) (- b)))
double code(double a, double b, double c) {
return fma(a, pow((c / -b), 2.0), c) / -b;
}
function code(a, b, c) return Float64(fma(a, (Float64(c / Float64(-b)) ^ 2.0), c) / Float64(-b)) end
code[a_, b_, c_] := N[(N[(a * N[Power[N[(c / (-b)), $MachinePrecision], 2.0], $MachinePrecision] + c), $MachinePrecision] / (-b)), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(a, {\left(\frac{c}{-b}\right)}^{2}, c\right)}{-b}
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in c around 0 96.3%
associate-*r/96.3%
neg-mul-196.3%
distribute-rgt-neg-in96.3%
Simplified96.3%
Taylor expanded in b around inf 96.2%
Taylor expanded in b around inf 96.6%
distribute-lft-out96.6%
associate-*r/96.6%
mul-1-neg96.6%
distribute-neg-frac296.6%
Simplified96.6%
Final simplification96.6%
(FPCore (a b c) :precision binary64 (* c (- (/ -1.0 b) (* c (/ a (pow b 3.0))))))
double code(double a, double b, double c) {
return c * ((-1.0 / b) - (c * (a / 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 * (((-1.0d0) / b) - (c * (a / (b ** 3.0d0))))
end function
public static double code(double a, double b, double c) {
return c * ((-1.0 / b) - (c * (a / Math.pow(b, 3.0))));
}
def code(a, b, c): return c * ((-1.0 / b) - (c * (a / math.pow(b, 3.0))))
function code(a, b, c) return Float64(c * Float64(Float64(-1.0 / b) - Float64(c * Float64(a / (b ^ 3.0))))) end
function tmp = code(a, b, c) tmp = c * ((-1.0 / b) - (c * (a / (b ^ 3.0)))); end
code[a_, b_, c_] := N[(c * N[(N[(-1.0 / b), $MachinePrecision] - N[(c * N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(\frac{-1}{b} - c \cdot \frac{a}{{b}^{3}}\right)
\end{array}
Initial program 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in c around 0 96.3%
associate-*r/96.3%
neg-mul-196.3%
distribute-rgt-neg-in96.3%
Simplified96.3%
Taylor expanded in c around 0 96.3%
sub-neg96.3%
associate-*r/96.3%
mul-1-neg96.3%
distribute-rgt-neg-out96.3%
associate-*r/96.3%
+-commutative96.3%
associate-*r/96.3%
distribute-rgt-neg-out96.3%
distribute-frac-neg96.3%
unsub-neg96.3%
distribute-neg-frac96.3%
metadata-eval96.3%
*-commutative96.3%
associate-*r/96.3%
Simplified96.3%
Final simplification96.3%
(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 13.6%
*-commutative13.6%
Simplified13.6%
Taylor expanded in b around inf 93.2%
associate-*r/93.2%
mul-1-neg93.2%
Simplified93.2%
Final simplification93.2%
herbie shell --seed 2024096
(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)))