
(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 11 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 (/ (* 2.0 c) (* b -2.0)))
(t_1 (sqrt (- (* b b) (* c (* 4.0 a))))))
(if (<= b -1e+154)
(if (>= b 0.0) t_0 (- (/ c b) (/ b a)))
(if (<= b 4.2e+91)
(if (>= b 0.0) (/ (* 2.0 c) (- (- b) t_1)) (/ (- t_1 b) (* 2.0 a)))
(if (>= b 0.0) t_0 (/ c b))))))
double code(double a, double b, double c) {
double t_0 = (2.0 * c) / (b * -2.0);
double t_1 = sqrt(((b * b) - (c * (4.0 * a))));
double tmp_1;
if (b <= -1e+154) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_0;
} else {
tmp_2 = (c / b) - (b / a);
}
tmp_1 = tmp_2;
} else if (b <= 4.2e+91) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (2.0 * c) / (-b - t_1);
} else {
tmp_3 = (t_1 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = c / b;
}
return tmp_1;
}
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) :: t_1
real(8) :: tmp
real(8) :: tmp_1
real(8) :: tmp_2
real(8) :: tmp_3
t_0 = (2.0d0 * c) / (b * (-2.0d0))
t_1 = sqrt(((b * b) - (c * (4.0d0 * a))))
if (b <= (-1d+154)) then
if (b >= 0.0d0) then
tmp_2 = t_0
else
tmp_2 = (c / b) - (b / a)
end if
tmp_1 = tmp_2
else if (b <= 4.2d+91) then
if (b >= 0.0d0) then
tmp_3 = (2.0d0 * c) / (-b - t_1)
else
tmp_3 = (t_1 - b) / (2.0d0 * a)
end if
tmp_1 = tmp_3
else if (b >= 0.0d0) then
tmp_1 = t_0
else
tmp_1 = c / b
end if
code = tmp_1
end function
public static double code(double a, double b, double c) {
double t_0 = (2.0 * c) / (b * -2.0);
double t_1 = Math.sqrt(((b * b) - (c * (4.0 * a))));
double tmp_1;
if (b <= -1e+154) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_0;
} else {
tmp_2 = (c / b) - (b / a);
}
tmp_1 = tmp_2;
} else if (b <= 4.2e+91) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (2.0 * c) / (-b - t_1);
} else {
tmp_3 = (t_1 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = c / b;
}
return tmp_1;
}
def code(a, b, c): t_0 = (2.0 * c) / (b * -2.0) t_1 = math.sqrt(((b * b) - (c * (4.0 * a)))) tmp_1 = 0 if b <= -1e+154: tmp_2 = 0 if b >= 0.0: tmp_2 = t_0 else: tmp_2 = (c / b) - (b / a) tmp_1 = tmp_2 elif b <= 4.2e+91: tmp_3 = 0 if b >= 0.0: tmp_3 = (2.0 * c) / (-b - t_1) else: tmp_3 = (t_1 - b) / (2.0 * a) tmp_1 = tmp_3 elif b >= 0.0: tmp_1 = t_0 else: tmp_1 = c / b return tmp_1
function code(a, b, c) t_0 = Float64(Float64(2.0 * c) / Float64(b * -2.0)) t_1 = sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) tmp_1 = 0.0 if (b <= -1e+154) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = t_0; else tmp_2 = Float64(Float64(c / b) - Float64(b / a)); end tmp_1 = tmp_2; elseif (b <= 4.2e+91) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(2.0 * c) / Float64(Float64(-b) - t_1)); else tmp_3 = Float64(Float64(t_1 - b) / Float64(2.0 * a)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = t_0; else tmp_1 = Float64(c / b); end return tmp_1 end
function tmp_5 = code(a, b, c) t_0 = (2.0 * c) / (b * -2.0); t_1 = sqrt(((b * b) - (c * (4.0 * a)))); tmp_2 = 0.0; if (b <= -1e+154) tmp_3 = 0.0; if (b >= 0.0) tmp_3 = t_0; else tmp_3 = (c / b) - (b / a); end tmp_2 = tmp_3; elseif (b <= 4.2e+91) tmp_4 = 0.0; if (b >= 0.0) tmp_4 = (2.0 * c) / (-b - t_1); else tmp_4 = (t_1 - b) / (2.0 * a); end tmp_2 = tmp_4; elseif (b >= 0.0) tmp_2 = t_0; else tmp_2 = c / b; end tmp_5 = tmp_2; end
code[a_, b_, c_] := Block[{t$95$0 = N[(N[(2.0 * c), $MachinePrecision] / N[(b * -2.0), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[b, -1e+154], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 4.2e+91], If[GreaterEqual[b, 0.0], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) - t$95$1), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$1 - b), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], t$95$0, N[(c / b), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{2 \cdot c}{b \cdot -2}\\
t_1 := \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\\
\mathbf{if}\;b \leq -1 \cdot 10^{+154}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} - \frac{b}{a}\\
\end{array}\\
\mathbf{elif}\;b \leq 4.2 \cdot 10^{+91}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) - t\_1}\\
\mathbf{else}:\\
\;\;\;\;\frac{t\_1 - b}{2 \cdot a}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b}\\
\end{array}
\end{array}
if b < -1.00000000000000004e154Initial program 50.3%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6450.3
Applied rewrites50.3%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6496.8
Applied rewrites96.8%
Taylor expanded in b around -inf
associate-*r*N/A
lower-*.f64N/A
mul-1-negN/A
lower-neg.f64N/A
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f6496.7
Applied rewrites96.7%
Taylor expanded in a around inf
Applied rewrites97.6%
if -1.00000000000000004e154 < b < 4.20000000000000015e91Initial program 86.0%
if 4.20000000000000015e91 < b Initial program 66.2%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6498.3
Applied rewrites98.3%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6498.3
Applied rewrites98.3%
Taylor expanded in b around -inf
associate-*r*N/A
lower-*.f64N/A
mul-1-negN/A
lower-neg.f64N/A
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f6498.3
Applied rewrites98.3%
Taylor expanded in b around 0
Applied rewrites98.3%
Final simplification90.4%
(FPCore (a b c)
:precision binary64
(let* ((t_0 (/ (* 2.0 c) (* b -2.0))))
(if (<= b -1e+154)
(if (>= b 0.0) t_0 (- (/ c b) (/ b a)))
(if (<= b 4.2e+91)
(if (>= b 0.0)
(* c (/ 2.0 (- (- b) (sqrt (fma c (* a -4.0) (* b b))))))
(/ (- (sqrt (- (* b b) (* c (* 4.0 a)))) b) (* 2.0 a)))
(if (>= b 0.0) t_0 (/ c b))))))
double code(double a, double b, double c) {
double t_0 = (2.0 * c) / (b * -2.0);
double tmp_1;
if (b <= -1e+154) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_0;
} else {
tmp_2 = (c / b) - (b / a);
}
tmp_1 = tmp_2;
} else if (b <= 4.2e+91) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = c * (2.0 / (-b - sqrt(fma(c, (a * -4.0), (b * b)))));
} else {
tmp_3 = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = c / b;
}
return tmp_1;
}
function code(a, b, c) t_0 = Float64(Float64(2.0 * c) / Float64(b * -2.0)) tmp_1 = 0.0 if (b <= -1e+154) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = t_0; else tmp_2 = Float64(Float64(c / b) - Float64(b / a)); end tmp_1 = tmp_2; elseif (b <= 4.2e+91) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(c * Float64(2.0 / Float64(Float64(-b) - sqrt(fma(c, Float64(a * -4.0), Float64(b * b)))))); else tmp_3 = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) - b) / Float64(2.0 * a)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = t_0; else tmp_1 = Float64(c / b); end return tmp_1 end
code[a_, b_, c_] := Block[{t$95$0 = N[(N[(2.0 * c), $MachinePrecision] / N[(b * -2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[b, -1e+154], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 4.2e+91], If[GreaterEqual[b, 0.0], N[(c * N[(2.0 / N[((-b) - N[Sqrt[N[(c * N[(a * -4.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $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]], If[GreaterEqual[b, 0.0], t$95$0, N[(c / b), $MachinePrecision]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{2 \cdot c}{b \cdot -2}\\
\mathbf{if}\;b \leq -1 \cdot 10^{+154}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} - \frac{b}{a}\\
\end{array}\\
\mathbf{elif}\;b \leq 4.2 \cdot 10^{+91}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{2}{\left(-b\right) - \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}\\
\mathbf{else}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)} - b}{2 \cdot a}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b}\\
\end{array}
\end{array}
if b < -1.00000000000000004e154Initial program 42.6%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6442.6
Applied rewrites42.6%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6497.8
Applied rewrites97.8%
Taylor expanded in b around -inf
associate-*r*N/A
lower-*.f64N/A
mul-1-negN/A
lower-neg.f64N/A
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f6497.8
Applied rewrites97.8%
Taylor expanded in a around inf
Applied rewrites98.1%
if -1.00000000000000004e154 < b < 4.20000000000000015e91Initial program 87.3%
Applied rewrites87.2%
if 4.20000000000000015e91 < b Initial program 51.6%
Taylor expanded in b around inf
*-commutativeN/A
lower-*.f6495.4
Applied rewrites95.4%
Taylor expanded in b around -inf
*-commutativeN/A
lower-*.f6495.4
Applied rewrites95.4%
Taylor expanded in b around -inf
associate-*r*N/A
lower-*.f64N/A
mul-1-negN/A
lower-neg.f64N/A
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f6495.4
Applied rewrites95.4%
Taylor expanded in b around 0
Applied rewrites95.4%
Final simplification90.8%
herbie shell --seed 2024223
(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))))