
(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
(-
(-
(fma
-2.0
(* (/ (pow c 3.0) (pow b 5.0)) (* a a))
(/ (/ (* -5.0 (* (pow a 3.0) (pow c 4.0))) (pow b 6.0)) b))
(/ c b))
(* a (/ c (/ (pow b 3.0) c)))))
double code(double a, double b, double c) {
return (fma(-2.0, ((pow(c, 3.0) / pow(b, 5.0)) * (a * a)), (((-5.0 * (pow(a, 3.0) * pow(c, 4.0))) / pow(b, 6.0)) / b)) - (c / b)) - (a * (c / (pow(b, 3.0) / c)));
}
function code(a, b, c) return Float64(Float64(fma(-2.0, Float64(Float64((c ^ 3.0) / (b ^ 5.0)) * Float64(a * a)), Float64(Float64(Float64(-5.0 * Float64((a ^ 3.0) * (c ^ 4.0))) / (b ^ 6.0)) / b)) - Float64(c / b)) - Float64(a * Float64(c / Float64((b ^ 3.0) / c)))) end
code[a_, b_, c_] := N[(N[(N[(-2.0 * N[(N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(-5.0 * N[(N[Power[a, 3.0], $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(a * N[(c / N[(N[Power[b, 3.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(-2, \frac{{c}^{3}}{{b}^{5}} \cdot \left(a \cdot a\right), \frac{\frac{-5 \cdot \left({a}^{3} \cdot {c}^{4}\right)}{{b}^{6}}}{b}\right) - \frac{c}{b}\right) - a \cdot \frac{c}{\frac{{b}^{3}}{c}}
\end{array}
Initial program 18.3%
Taylor expanded in a around 0 98.0%
Simplified98.0%
Taylor expanded in c around 0 98.0%
associate-*r/98.0%
*-commutative98.0%
Simplified98.0%
Final simplification98.0%
(FPCore (a b c) :precision binary64 (- (fma -0.25 (* (/ (pow (* c a) 4.0) a) (/ 20.0 (pow b 7.0))) (- (/ (* -2.0 (* a (* (pow c 3.0) a))) (pow b 5.0)) (/ c b))) (* a (/ c (/ (* b (* b b)) c)))))
double code(double a, double b, double c) {
return fma(-0.25, ((pow((c * a), 4.0) / a) * (20.0 / pow(b, 7.0))), (((-2.0 * (a * (pow(c, 3.0) * a))) / pow(b, 5.0)) - (c / b))) - (a * (c / ((b * (b * b)) / c)));
}
function code(a, b, c) return Float64(fma(-0.25, Float64(Float64((Float64(c * a) ^ 4.0) / a) * Float64(20.0 / (b ^ 7.0))), Float64(Float64(Float64(-2.0 * Float64(a * Float64((c ^ 3.0) * a))) / (b ^ 5.0)) - Float64(c / b))) - Float64(a * Float64(c / Float64(Float64(b * Float64(b * b)) / c)))) end
code[a_, b_, c_] := N[(N[(-0.25 * N[(N[(N[Power[N[(c * a), $MachinePrecision], 4.0], $MachinePrecision] / a), $MachinePrecision] * N[(20.0 / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(-2.0 * N[(a * N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(a * N[(c / N[(N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.25, \frac{{\left(c \cdot a\right)}^{4}}{a} \cdot \frac{20}{{b}^{7}}, \frac{-2 \cdot \left(a \cdot \left({c}^{3} \cdot a\right)\right)}{{b}^{5}} - \frac{c}{b}\right) - a \cdot \frac{c}{\frac{b \cdot \left(b \cdot b\right)}{c}}
\end{array}
Initial program 18.3%
Taylor expanded in b around inf 98.0%
Simplified98.0%
Taylor expanded in c around 0 98.0%
distribute-rgt-out98.0%
associate-*r*98.0%
times-frac98.0%
Simplified98.0%
unpow395.3%
Applied egg-rr98.0%
Final simplification98.0%
(FPCore (a b c) :precision binary64 (- (- (/ (* -2.0 (* a (* (pow c 3.0) a))) (pow b 5.0)) (/ c b)) (* a (/ c (/ (pow b 3.0) c)))))
double code(double a, double b, double c) {
return (((-2.0 * (a * (pow(c, 3.0) * a))) / pow(b, 5.0)) - (c / b)) - (a * (c / (pow(b, 3.0) / c)));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = ((((-2.0d0) * (a * ((c ** 3.0d0) * a))) / (b ** 5.0d0)) - (c / b)) - (a * (c / ((b ** 3.0d0) / c)))
end function
public static double code(double a, double b, double c) {
return (((-2.0 * (a * (Math.pow(c, 3.0) * a))) / Math.pow(b, 5.0)) - (c / b)) - (a * (c / (Math.pow(b, 3.0) / c)));
}
def code(a, b, c): return (((-2.0 * (a * (math.pow(c, 3.0) * a))) / math.pow(b, 5.0)) - (c / b)) - (a * (c / (math.pow(b, 3.0) / c)))
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * Float64(a * Float64((c ^ 3.0) * a))) / (b ^ 5.0)) - Float64(c / b)) - Float64(a * Float64(c / Float64((b ^ 3.0) / c)))) end
function tmp = code(a, b, c) tmp = (((-2.0 * (a * ((c ^ 3.0) * a))) / (b ^ 5.0)) - (c / b)) - (a * (c / ((b ^ 3.0) / c))); end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[(a * N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(a * N[(c / N[(N[Power[b, 3.0], $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2 \cdot \left(a \cdot \left({c}^{3} \cdot a\right)\right)}{{b}^{5}} - \frac{c}{b}\right) - a \cdot \frac{c}{\frac{{b}^{3}}{c}}
\end{array}
Initial program 18.3%
Taylor expanded in b around inf 97.0%
+-commutative97.0%
mul-1-neg97.0%
unsub-neg97.0%
+-commutative97.0%
mul-1-neg97.0%
unsub-neg97.0%
associate-*r/97.0%
*-commutative97.0%
unpow297.0%
associate-*l*97.0%
associate-/l*97.0%
associate-/r/97.0%
Simplified97.0%
Final simplification97.0%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (/ (* c a) (/ (* b (* b b)) c))))
double code(double a, double b, double c) {
return (-c / b) - ((c * a) / ((b * (b * b)) / c));
}
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) - ((c * a) / ((b * (b * b)) / c))
end function
public static double code(double a, double b, double c) {
return (-c / b) - ((c * a) / ((b * (b * b)) / c));
}
def code(a, b, c): return (-c / b) - ((c * a) / ((b * (b * b)) / c))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(Float64(c * a) / Float64(Float64(b * Float64(b * b)) / c))) end
function tmp = code(a, b, c) tmp = (-c / b) - ((c * a) / ((b * (b * b)) / c)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[(c * a), $MachinePrecision] / N[(N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{c \cdot a}{\frac{b \cdot \left(b \cdot b\right)}{c}}
\end{array}
Initial program 18.3%
Taylor expanded in b around inf 95.3%
+-commutative95.3%
mul-1-neg95.3%
unsub-neg95.3%
mul-1-neg95.3%
associate-/l*95.3%
associate-/r/95.3%
unpow295.3%
associate-/l*95.3%
Simplified95.3%
associate-*l/95.3%
Applied egg-rr95.3%
unpow395.3%
Applied egg-rr95.3%
Final simplification95.3%
(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(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 18.3%
Taylor expanded in b around inf 90.3%
mul-1-neg90.3%
Simplified90.3%
Final simplification90.3%
herbie shell --seed 2023274
(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)))