
(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
(+
(* -2.0 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0)))
(-
(-
(* -0.25 (* (/ (pow (* a c) 4.0) (pow b 7.0)) (/ 20.0 a)))
(/ (* a (pow c 2.0)) (pow b 3.0)))
(/ c b))))
double code(double a, double b, double c) {
return (-2.0 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + (((-0.25 * ((pow((a * c), 4.0) / pow(b, 7.0)) * (20.0 / a))) - ((a * 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 = ((-2.0d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + ((((-0.25d0) * ((((a * c) ** 4.0d0) / (b ** 7.0d0)) * (20.0d0 / a))) - ((a * (c ** 2.0d0)) / (b ** 3.0d0))) - (c / b))
end function
public static double code(double a, double b, double c) {
return (-2.0 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + (((-0.25 * ((Math.pow((a * c), 4.0) / Math.pow(b, 7.0)) * (20.0 / a))) - ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0))) - (c / b));
}
def code(a, b, c): return (-2.0 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + (((-0.25 * ((math.pow((a * c), 4.0) / math.pow(b, 7.0)) * (20.0 / a))) - ((a * math.pow(c, 2.0)) / math.pow(b, 3.0))) - (c / b))
function code(a, b, c) return Float64(Float64(-2.0 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(Float64(-0.25 * Float64(Float64((Float64(a * c) ^ 4.0) / (b ^ 7.0)) * Float64(20.0 / a))) - Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0))) - Float64(c / b))) end
function tmp = code(a, b, c) tmp = (-2.0 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + (((-0.25 * ((((a * c) ^ 4.0) / (b ^ 7.0)) * (20.0 / a))) - ((a * (c ^ 2.0)) / (b ^ 3.0))) - (c / b)); end
code[a_, b_, c_] := N[(N[(-2.0 * N[(N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(-0.25 * N[(N[(N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision] * N[(20.0 / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-2 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(\left(-0.25 \cdot \left(\frac{{\left(a \cdot c\right)}^{4}}{{b}^{7}} \cdot \frac{20}{a}\right) - \frac{a \cdot {c}^{2}}{{b}^{3}}\right) - \frac{c}{b}\right)
\end{array}
Initial program 32.8%
*-commutative32.8%
Simplified32.8%
Taylor expanded in b around inf 94.8%
Taylor expanded in c around 0 94.8%
distribute-rgt-out94.8%
associate-*l*94.8%
*-commutative94.8%
*-commutative94.8%
times-frac94.8%
Simplified94.8%
Final simplification94.8%
(FPCore (a b c) :precision binary64 (- (- (/ -2.0 (/ (pow b 5.0) (* (pow a 2.0) (pow c 3.0)))) (/ c b)) (* (/ a (pow b 3.0)) (* c c))))
double code(double a, double b, double c) {
return ((-2.0 / (pow(b, 5.0) / (pow(a, 2.0) * pow(c, 3.0)))) - (c / b)) - ((a / pow(b, 3.0)) * (c * 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) / ((b ** 5.0d0) / ((a ** 2.0d0) * (c ** 3.0d0)))) - (c / b)) - ((a / (b ** 3.0d0)) * (c * c))
end function
public static double code(double a, double b, double c) {
return ((-2.0 / (Math.pow(b, 5.0) / (Math.pow(a, 2.0) * Math.pow(c, 3.0)))) - (c / b)) - ((a / Math.pow(b, 3.0)) * (c * c));
}
def code(a, b, c): return ((-2.0 / (math.pow(b, 5.0) / (math.pow(a, 2.0) * math.pow(c, 3.0)))) - (c / b)) - ((a / math.pow(b, 3.0)) * (c * c))
function code(a, b, c) return Float64(Float64(Float64(-2.0 / Float64((b ^ 5.0) / Float64((a ^ 2.0) * (c ^ 3.0)))) - Float64(c / b)) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))) end
function tmp = code(a, b, c) tmp = ((-2.0 / ((b ^ 5.0) / ((a ^ 2.0) * (c ^ 3.0)))) - (c / b)) - ((a / (b ^ 3.0)) * (c * c)); end
code[a_, b_, c_] := N[(N[(N[(-2.0 / N[(N[Power[b, 5.0], $MachinePrecision] / N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2}{\frac{{b}^{5}}{{a}^{2} \cdot {c}^{3}}} - \frac{c}{b}\right) - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)
\end{array}
Initial program 32.8%
*-commutative32.8%
Simplified32.8%
Taylor expanded in b around inf 93.2%
associate-+r+93.2%
mul-1-neg93.2%
unsub-neg93.2%
mul-1-neg93.2%
unsub-neg93.2%
associate-*r/93.2%
associate-/l*93.2%
*-commutative93.2%
associate-/l*93.2%
associate-/r/93.2%
Simplified93.2%
unpow290.0%
Applied egg-rr93.2%
Final simplification93.2%
(FPCore (a b c) :precision binary64 (if (<= b 9.2e-7) (/ (- (sqrt (fma b b (* c (* a -4.0)))) b) (* a 2.0)) (- (/ (- c) b) (* (/ a (pow b 3.0)) (* c c)))))
double code(double a, double b, double c) {
double tmp;
if (b <= 9.2e-7) {
tmp = (sqrt(fma(b, b, (c * (a * -4.0)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / pow(b, 3.0)) * (c * c));
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= 9.2e-7) tmp = Float64(Float64(sqrt(fma(b, b, Float64(c * Float64(a * -4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(Float64(Float64(-c) / b) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, 9.2e-7], N[(N[(N[Sqrt[N[(b * b + N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 9.2 \cdot 10^{-7}:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{-c}{b} - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)\\
\end{array}
\end{array}
if b < 9.1999999999999998e-7Initial program 87.0%
sqr-neg87.0%
+-commutative87.0%
unsub-neg87.0%
sqr-neg87.0%
fma-neg87.1%
distribute-lft-neg-in87.1%
*-commutative87.1%
*-commutative87.1%
distribute-rgt-neg-in87.1%
metadata-eval87.1%
*-commutative87.1%
Simplified87.1%
if 9.1999999999999998e-7 < b Initial program 29.9%
*-commutative29.9%
Simplified29.9%
Taylor expanded in b around inf 92.1%
mul-1-neg92.1%
unsub-neg92.1%
mul-1-neg92.1%
distribute-neg-frac92.1%
associate-/l*92.1%
associate-/r/92.1%
Simplified92.1%
unpow292.1%
Applied egg-rr92.1%
Final simplification91.8%
(FPCore (a b c) :precision binary64 (if (<= b 1.4e-6) (/ (- (sqrt (- (* b b) (* c (* a 4.0)))) b) (* a 2.0)) (- (/ (- c) b) (* (/ a (pow b 3.0)) (* c c)))))
double code(double a, double b, double c) {
double tmp;
if (b <= 1.4e-6) {
tmp = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / pow(b, 3.0)) * (c * c));
}
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 <= 1.4d-6) then
tmp = (sqrt(((b * b) - (c * (a * 4.0d0)))) - b) / (a * 2.0d0)
else
tmp = (-c / b) - ((a / (b ** 3.0d0)) * (c * c))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 1.4e-6) {
tmp = (Math.sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
} else {
tmp = (-c / b) - ((a / Math.pow(b, 3.0)) * (c * c));
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 1.4e-6: tmp = (math.sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0) else: tmp = (-c / b) - ((a / math.pow(b, 3.0)) * (c * c)) return tmp
function code(a, b, c) tmp = 0.0 if (b <= 1.4e-6) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(Float64(Float64(-c) / b) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 1.4e-6) tmp = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0); else tmp = (-c / b) - ((a / (b ^ 3.0)) * (c * c)); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 1.4e-6], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.4 \cdot 10^{-6}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{-c}{b} - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)\\
\end{array}
\end{array}
if b < 1.39999999999999994e-6Initial program 87.0%
if 1.39999999999999994e-6 < b Initial program 29.9%
*-commutative29.9%
Simplified29.9%
Taylor expanded in b around inf 92.1%
mul-1-neg92.1%
unsub-neg92.1%
mul-1-neg92.1%
distribute-neg-frac92.1%
associate-/l*92.1%
associate-/r/92.1%
Simplified92.1%
unpow292.1%
Applied egg-rr92.1%
Final simplification91.8%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (* (/ a (pow b 3.0)) (* c c))))
double code(double a, double b, double c) {
return (-c / b) - ((a / pow(b, 3.0)) * (c * 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) - ((a / (b ** 3.0d0)) * (c * c))
end function
public static double code(double a, double b, double c) {
return (-c / b) - ((a / Math.pow(b, 3.0)) * (c * c));
}
def code(a, b, c): return (-c / b) - ((a / math.pow(b, 3.0)) * (c * c))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(Float64(a / (b ^ 3.0)) * Float64(c * c))) end
function tmp = code(a, b, c) tmp = (-c / b) - ((a / (b ^ 3.0)) * (c * c)); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(N[(a / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{a}{{b}^{3}} \cdot \left(c \cdot c\right)
\end{array}
Initial program 32.8%
*-commutative32.8%
Simplified32.8%
Taylor expanded in b around inf 90.0%
mul-1-neg90.0%
unsub-neg90.0%
mul-1-neg90.0%
distribute-neg-frac90.0%
associate-/l*90.0%
associate-/r/90.0%
Simplified90.0%
unpow290.0%
Applied egg-rr90.0%
Final simplification90.0%
(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 32.8%
*-commutative32.8%
Simplified32.8%
Taylor expanded in b around inf 80.6%
mul-1-neg80.6%
distribute-neg-frac80.6%
Simplified80.6%
Final simplification80.6%
herbie shell --seed 2023319
(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)))