
(FPCore (a b c) :precision binary64 (let* ((t_0 (sqrt (- (* b b) (* (* 4.0 a) c))))) (if (>= b 0.0) (/ (* 2.0 c) (- (- b) t_0)) (/ (+ (- b) t_0) (* 2.0 a)))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b >= 0.0) {
tmp = (2.0 * c) / (-b - t_0);
} else {
tmp = (-b + t_0) / (2.0 * a);
}
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) :: t_0
real(8) :: tmp
t_0 = sqrt(((b * b) - ((4.0d0 * a) * c)))
if (b >= 0.0d0) then
tmp = (2.0d0 * c) / (-b - t_0)
else
tmp = (-b + t_0) / (2.0d0 * a)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double t_0 = Math.sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b >= 0.0) {
tmp = (2.0 * c) / (-b - t_0);
} else {
tmp = (-b + t_0) / (2.0 * a);
}
return tmp;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - ((4.0 * a) * c))) tmp = 0 if b >= 0.0: tmp = (2.0 * c) / (-b - t_0) else: tmp = (-b + t_0) / (2.0 * a) return tmp
function code(a, b, c) t_0 = sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c))) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(2.0 * c) / Float64(Float64(-b) - t_0)); else tmp = Float64(Float64(Float64(-b) + t_0) / Float64(2.0 * a)); end return tmp end
function tmp_2 = code(a, b, c) t_0 = sqrt(((b * b) - ((4.0 * a) * c))); tmp = 0.0; if (b >= 0.0) tmp = (2.0 * c) / (-b - t_0); else tmp = (-b + t_0) / (2.0 * a); end tmp_2 = tmp; end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[GreaterEqual[b, 0.0], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) - t$95$0), $MachinePrecision]), $MachinePrecision], N[(N[((-b) + t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}\\
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) - t\_0}\\
\mathbf{else}:\\
\;\;\;\;\frac{\left(-b\right) + t\_0}{2 \cdot a}\\
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c) :precision binary64 (let* ((t_0 (sqrt (- (* b b) (* (* 4.0 a) c))))) (if (>= b 0.0) (/ (* 2.0 c) (- (- b) t_0)) (/ (+ (- b) t_0) (* 2.0 a)))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b >= 0.0) {
tmp = (2.0 * c) / (-b - t_0);
} else {
tmp = (-b + t_0) / (2.0 * a);
}
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) :: t_0
real(8) :: tmp
t_0 = sqrt(((b * b) - ((4.0d0 * a) * c)))
if (b >= 0.0d0) then
tmp = (2.0d0 * c) / (-b - t_0)
else
tmp = (-b + t_0) / (2.0d0 * a)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double t_0 = Math.sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b >= 0.0) {
tmp = (2.0 * c) / (-b - t_0);
} else {
tmp = (-b + t_0) / (2.0 * a);
}
return tmp;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - ((4.0 * a) * c))) tmp = 0 if b >= 0.0: tmp = (2.0 * c) / (-b - t_0) else: tmp = (-b + t_0) / (2.0 * a) return tmp
function code(a, b, c) t_0 = sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c))) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(2.0 * c) / Float64(Float64(-b) - t_0)); else tmp = Float64(Float64(Float64(-b) + t_0) / Float64(2.0 * a)); end return tmp end
function tmp_2 = code(a, b, c) t_0 = sqrt(((b * b) - ((4.0 * a) * c))); tmp = 0.0; if (b >= 0.0) tmp = (2.0 * c) / (-b - t_0); else tmp = (-b + t_0) / (2.0 * a); end tmp_2 = tmp; end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[GreaterEqual[b, 0.0], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) - t$95$0), $MachinePrecision]), $MachinePrecision], N[(N[((-b) + t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}\\
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) - t\_0}\\
\mathbf{else}:\\
\;\;\;\;\frac{\left(-b\right) + t\_0}{2 \cdot a}\\
\end{array}
\end{array}
(FPCore (a b c)
:precision binary64
(let* ((t_0 (sqrt (fma c (* a -4.0) (* b b)))) (t_1 (/ b (- a))))
(if (<= b -3e+153)
(if (>= b 0.0) t_1 t_1)
(if (<= b 2.6e+66)
(if (>= b 0.0) (* (/ c (+ b t_0)) -2.0) (/ (- t_0 b) (* 2.0 a)))
(if (>= b 0.0)
(/ (* 2.0 c) (- (- b) (fma (/ c b) (* a -2.0) b)))
(/ (- (sqrt (- (* b b) (* c (* 4.0 a)))) b) (* 2.0 a)))))))
double code(double a, double b, double c) {
double t_0 = sqrt(fma(c, (a * -4.0), (b * b)));
double t_1 = b / -a;
double tmp_1;
if (b <= -3e+153) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_1;
} else {
tmp_2 = t_1;
}
tmp_1 = tmp_2;
} else if (b <= 2.6e+66) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c / (b + t_0)) * -2.0;
} else {
tmp_3 = (t_0 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = (2.0 * c) / (-b - fma((c / b), (a * -2.0), b));
} else {
tmp_1 = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (2.0 * a);
}
return tmp_1;
}
function code(a, b, c) t_0 = sqrt(fma(c, Float64(a * -4.0), Float64(b * b))) t_1 = Float64(b / Float64(-a)) tmp_1 = 0.0 if (b <= -3e+153) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = t_1; else tmp_2 = t_1; end tmp_1 = tmp_2; elseif (b <= 2.6e+66) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(c / Float64(b + t_0)) * -2.0); else tmp_3 = Float64(Float64(t_0 - b) / Float64(2.0 * a)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = Float64(Float64(2.0 * c) / Float64(Float64(-b) - fma(Float64(c / b), Float64(a * -2.0), b))); else tmp_1 = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) - b) / Float64(2.0 * a)); end return tmp_1 end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(c * N[(a * -4.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(b / (-a)), $MachinePrecision]}, If[LessEqual[b, -3e+153], If[GreaterEqual[b, 0.0], t$95$1, t$95$1], If[LessEqual[b, 2.6e+66], If[GreaterEqual[b, 0.0], N[(N[(c / N[(b + t$95$0), $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision], N[(N[(t$95$0 - b), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) - N[(N[(c / b), $MachinePrecision] * N[(a * -2.0), $MachinePrecision] + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}\\
t_1 := \frac{b}{-a}\\
\mathbf{if}\;b \leq -3 \cdot 10^{+153}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t\_1\\
\mathbf{else}:\\
\;\;\;\;t\_1\\
\end{array}\\
\mathbf{elif}\;b \leq 2.6 \cdot 10^{+66}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{c}{b + t\_0} \cdot -2\\
\mathbf{else}:\\
\;\;\;\;\frac{t\_0 - b}{2 \cdot a}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) - \mathsf{fma}\left(\frac{c}{b}, a \cdot -2, b\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)} - b}{2 \cdot a}\\
\end{array}
\end{array}
if b < -3.00000000000000019e153Initial program 33.4%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6433.4
Applied rewrites33.4%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6498.3
Applied rewrites98.3%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6498.3
Applied rewrites98.3%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6498.3
Applied rewrites98.3%
if -3.00000000000000019e153 < b < 2.60000000000000012e66Initial program 89.4%
Applied rewrites89.9%
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6489.9
lift--.f64N/A
sub-negN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
*-commutativeN/A
lift-*.f64N/A
+-commutativeN/A
lift-fma.f6489.9
Applied rewrites89.9%
lift-*.f64N/A
lift-/.f64N/A
clear-numN/A
un-div-invN/A
lift-neg.f64N/A
neg-mul-1N/A
*-commutativeN/A
div-invN/A
metadata-evalN/A
times-fracN/A
metadata-evalN/A
lower-*.f64N/A
lower-/.f6490.0
Applied rewrites90.0%
if 2.60000000000000012e66 < b Initial program 62.9%
Taylor expanded in a around 0
+-commutativeN/A
associate-*r/N/A
*-commutativeN/A
associate-*r*N/A
associate-*l/N/A
associate-*r/N/A
*-commutativeN/A
associate-*l*N/A
lower-fma.f64N/A
lower-/.f64N/A
lower-*.f6495.4
Applied rewrites95.4%
Final simplification92.3%
(FPCore (a b c)
:precision binary64
(let* ((t_0 (sqrt (fma c (* a -4.0) (* b b)))) (t_1 (/ b (- a))))
(if (<= b -3e+153)
(if (>= b 0.0) t_1 t_1)
(if (<= b 2.6e+66)
(if (>= b 0.0) (* (/ c (+ b t_0)) -2.0) (/ (- t_0 b) (* 2.0 a)))
(if (>= b 0.0)
(/ (* 2.0 c) (* b -2.0))
(/ (- (sqrt (* b b)) b) (* 2.0 a)))))))
double code(double a, double b, double c) {
double t_0 = sqrt(fma(c, (a * -4.0), (b * b)));
double t_1 = b / -a;
double tmp_1;
if (b <= -3e+153) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_1;
} else {
tmp_2 = t_1;
}
tmp_1 = tmp_2;
} else if (b <= 2.6e+66) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c / (b + t_0)) * -2.0;
} else {
tmp_3 = (t_0 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = (2.0 * c) / (b * -2.0);
} else {
tmp_1 = (sqrt((b * b)) - b) / (2.0 * a);
}
return tmp_1;
}
function code(a, b, c) t_0 = sqrt(fma(c, Float64(a * -4.0), Float64(b * b))) t_1 = Float64(b / Float64(-a)) tmp_1 = 0.0 if (b <= -3e+153) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = t_1; else tmp_2 = t_1; end tmp_1 = tmp_2; elseif (b <= 2.6e+66) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(c / Float64(b + t_0)) * -2.0); else tmp_3 = Float64(Float64(t_0 - b) / Float64(2.0 * a)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = Float64(Float64(2.0 * c) / Float64(b * -2.0)); else tmp_1 = Float64(Float64(sqrt(Float64(b * b)) - b) / Float64(2.0 * a)); end return tmp_1 end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(c * N[(a * -4.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(b / (-a)), $MachinePrecision]}, If[LessEqual[b, -3e+153], If[GreaterEqual[b, 0.0], t$95$1, t$95$1], If[LessEqual[b, 2.6e+66], If[GreaterEqual[b, 0.0], N[(N[(c / N[(b + t$95$0), $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision], N[(N[(t$95$0 - b), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(N[(2.0 * c), $MachinePrecision] / N[(b * -2.0), $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(b * b), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}\\
t_1 := \frac{b}{-a}\\
\mathbf{if}\;b \leq -3 \cdot 10^{+153}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t\_1\\
\mathbf{else}:\\
\;\;\;\;t\_1\\
\end{array}\\
\mathbf{elif}\;b \leq 2.6 \cdot 10^{+66}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{c}{b + t\_0} \cdot -2\\
\mathbf{else}:\\
\;\;\;\;\frac{t\_0 - b}{2 \cdot a}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;\frac{2 \cdot c}{b \cdot -2}\\
\mathbf{else}:\\
\;\;\;\;\frac{\sqrt{b \cdot b} - b}{2 \cdot a}\\
\end{array}
\end{array}
if b < -3.00000000000000019e153Initial program 41.5%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6441.5
Applied rewrites41.5%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6497.6
Applied rewrites97.6%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6497.6
Applied rewrites97.6%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6497.7
Applied rewrites97.7%
if -3.00000000000000019e153 < b < 2.60000000000000012e66Initial program 86.5%
Applied rewrites86.5%
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6486.5
lift--.f64N/A
sub-negN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
metadata-evalN/A
*-commutativeN/A
lift-*.f64N/A
+-commutativeN/A
lift-fma.f6486.5
Applied rewrites86.5%
lift-*.f64N/A
lift-/.f64N/A
clear-numN/A
un-div-invN/A
lift-neg.f64N/A
neg-mul-1N/A
*-commutativeN/A
div-invN/A
metadata-evalN/A
times-fracN/A
metadata-evalN/A
lower-*.f64N/A
lower-/.f6486.5
Applied rewrites86.5%
if 2.60000000000000012e66 < b Initial program 58.4%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6494.4
Applied rewrites94.4%
Taylor expanded in b around inf
unpow2N/A
lower-*.f6494.4
Applied rewrites94.4%
Final simplification90.3%
herbie shell --seed 2024222
(FPCore (a b c)
:name "jeff quadratic root 2"
:precision binary64
(if (>= b 0.0) (/ (* 2.0 c) (- (- b) (sqrt (- (* b b) (* (* 4.0 a) c))))) (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a))))