
(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 5 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 (- (* b b) (* c (* a 4.0))))))
(if (<= b -5e+149)
(if (>= b 0.0) (* c (/ -1.0 b)) (/ (+ b b) (* a -2.0)))
(if (<= b 9e+101)
(if (>= b 0.0) (/ (* c 2.0) (- (- b) t_0)) (/ (- t_0 b) (* a 2.0)))
(if (>= b 0.0)
(/ (* c 2.0) (* 2.0 (fma a (/ c b) (- b))))
(/ 1.0 (/ b c)))))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -5e+149) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = c * (-1.0 / b);
} else {
tmp_2 = (b + b) / (a * -2.0);
}
tmp_1 = tmp_2;
} else if (b <= 9e+101) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c * 2.0) / (-b - t_0);
} else {
tmp_3 = (t_0 - b) / (a * 2.0);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = (c * 2.0) / (2.0 * fma(a, (c / b), -b));
} else {
tmp_1 = 1.0 / (b / c);
}
return tmp_1;
}
function code(a, b, c) t_0 = sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) tmp_1 = 0.0 if (b <= -5e+149) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = Float64(c * Float64(-1.0 / b)); else tmp_2 = Float64(Float64(b + b) / Float64(a * -2.0)); end tmp_1 = tmp_2; elseif (b <= 9e+101) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(c * 2.0) / Float64(Float64(-b) - t_0)); else tmp_3 = Float64(Float64(t_0 - b) / Float64(a * 2.0)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = Float64(Float64(c * 2.0) / Float64(2.0 * fma(a, Float64(c / b), Float64(-b)))); else tmp_1 = Float64(1.0 / Float64(b / c)); end return tmp_1 end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[b, -5e+149], If[GreaterEqual[b, 0.0], N[(c * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision], N[(N[(b + b), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 9e+101], If[GreaterEqual[b, 0.0], N[(N[(c * 2.0), $MachinePrecision] / N[((-b) - t$95$0), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$0 - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(N[(c * 2.0), $MachinePrecision] / N[(2.0 * N[(a * N[(c / b), $MachinePrecision] + (-b)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b / c), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)}\\
\mathbf{if}\;b \leq -5 \cdot 10^{+149}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{-1}{b}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + b}{a \cdot -2}\\
\end{array}\\
\mathbf{elif}\;b \leq 9 \cdot 10^{+101}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{c \cdot 2}{\left(-b\right) - t\_0}\\
\mathbf{else}:\\
\;\;\;\;\frac{t\_0 - b}{a \cdot 2}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;\frac{c \cdot 2}{2 \cdot \mathsf{fma}\left(a, \frac{c}{b}, -b\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{\frac{b}{c}}\\
\end{array}
\end{array}
if b < -4.9999999999999999e149Initial program 36.0%
Simplified36.1%
Taylor expanded in b around -inf 92.6%
Taylor expanded in b around inf 92.6%
if -4.9999999999999999e149 < b < 9.0000000000000004e101Initial program 86.6%
if 9.0000000000000004e101 < b Initial program 51.2%
Taylor expanded in a around 0 89.7%
distribute-lft-out--89.7%
associate-/l*96.6%
fma-neg96.6%
Simplified96.6%
clear-num96.6%
inv-pow96.6%
Applied egg-rr96.6%
unpow-196.6%
associate-*r/96.6%
*-commutative96.6%
associate-*r*96.6%
*-commutative96.6%
Simplified96.6%
Taylor expanded in b around -inf 96.6%
Final simplification89.7%
(FPCore (a b c)
:precision binary64
(if (<= b -1e+147)
(if (>= b 0.0) (* c (/ -1.0 b)) (/ (+ b b) (* a -2.0)))
(if (>= b 0.0)
(/ (* c 2.0) (* 2.0 (fma a (/ c b) (- b))))
(/ (- (sqrt (- (* b b) (* c (* a 4.0)))) b) (* a 2.0)))))
double code(double a, double b, double c) {
double tmp_1;
if (b <= -1e+147) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = c * (-1.0 / b);
} else {
tmp_2 = (b + b) / (a * -2.0);
}
tmp_1 = tmp_2;
} else if (b >= 0.0) {
tmp_1 = (c * 2.0) / (2.0 * fma(a, (c / b), -b));
} else {
tmp_1 = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
}
return tmp_1;
}
function code(a, b, c) tmp_1 = 0.0 if (b <= -1e+147) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = Float64(c * Float64(-1.0 / b)); else tmp_2 = Float64(Float64(b + b) / Float64(a * -2.0)); end tmp_1 = tmp_2; elseif (b >= 0.0) tmp_1 = Float64(Float64(c * 2.0) / Float64(2.0 * fma(a, Float64(c / b), Float64(-b)))); else tmp_1 = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) - b) / Float64(a * 2.0)); end return tmp_1 end
code[a_, b_, c_] := If[LessEqual[b, -1e+147], If[GreaterEqual[b, 0.0], N[(c * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision], N[(N[(b + b), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(N[(c * 2.0), $MachinePrecision] / N[(2.0 * N[(a * N[(c / b), $MachinePrecision] + (-b)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 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]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -1 \cdot 10^{+147}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{-1}{b}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + b}{a \cdot -2}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;\frac{c \cdot 2}{2 \cdot \mathsf{fma}\left(a, \frac{c}{b}, -b\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)} - b}{a \cdot 2}\\
\end{array}
\end{array}
if b < -9.9999999999999998e146Initial program 36.0%
Simplified36.1%
Taylor expanded in b around -inf 92.6%
Taylor expanded in b around inf 92.6%
if -9.9999999999999998e146 < b Initial program 77.6%
Taylor expanded in a around 0 73.7%
distribute-lft-out--73.7%
associate-/l*75.5%
fma-neg75.5%
Simplified75.5%
Final simplification78.0%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (* c (/ -2.0 (+ b (+ b (* -2.0 (* a (/ c b))))))) (/ (+ b b) (* a -2.0))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = c * (-2.0 / (b + (b + (-2.0 * (a * (c / b))))));
} else {
tmp = (b + b) / (a * -2.0);
}
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 >= 0.0d0) then
tmp = c * ((-2.0d0) / (b + (b + ((-2.0d0) * (a * (c / b))))))
else
tmp = (b + b) / (a * (-2.0d0))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = c * (-2.0 / (b + (b + (-2.0 * (a * (c / b))))));
} else {
tmp = (b + b) / (a * -2.0);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = c * (-2.0 / (b + (b + (-2.0 * (a * (c / b)))))) else: tmp = (b + b) / (a * -2.0) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(c * Float64(-2.0 / Float64(b + Float64(b + Float64(-2.0 * Float64(a * Float64(c / b))))))); else tmp = Float64(Float64(b + b) / Float64(a * -2.0)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = c * (-2.0 / (b + (b + (-2.0 * (a * (c / b)))))); else tmp = (b + b) / (a * -2.0); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[(c * N[(-2.0 / N[(b + N[(b + N[(-2.0 * N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(b + b), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{-2}{b + \left(b + -2 \cdot \left(a \cdot \frac{c}{b}\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + b}{a \cdot -2}\\
\end{array}
\end{array}
Initial program 71.5%
Simplified71.6%
Taylor expanded in b around -inf 70.2%
Taylor expanded in c around 0 66.8%
associate-/l*68.4%
Simplified68.4%
Final simplification68.4%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- c) b) (/ (+ b b) (* a -2.0))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -c / b;
} else {
tmp = (b + b) / (a * -2.0);
}
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 >= 0.0d0) then
tmp = -c / b
else
tmp = (b + b) / (a * (-2.0d0))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -c / b;
} else {
tmp = (b + b) / (a * -2.0);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -c / b else: tmp = (b + b) / (a * -2.0) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-c) / b); else tmp = Float64(Float64(b + b) / Float64(a * -2.0)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -c / b; else tmp = (b + b) / (a * -2.0); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-c) / b), $MachinePrecision], N[(N[(b + b), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-c}{b}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + b}{a \cdot -2}\\
\end{array}
\end{array}
Initial program 71.5%
Simplified71.6%
Taylor expanded in b around -inf 70.2%
Taylor expanded in c around 0 68.2%
associate-*r/68.2%
mul-1-neg68.2%
Simplified68.2%
Final simplification68.2%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (* c (/ -1.0 b)) (/ (+ b b) (* a -2.0))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = c * (-1.0 / b);
} else {
tmp = (b + b) / (a * -2.0);
}
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 >= 0.0d0) then
tmp = c * ((-1.0d0) / b)
else
tmp = (b + b) / (a * (-2.0d0))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = c * (-1.0 / b);
} else {
tmp = (b + b) / (a * -2.0);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = c * (-1.0 / b) else: tmp = (b + b) / (a * -2.0) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(c * Float64(-1.0 / b)); else tmp = Float64(Float64(b + b) / Float64(a * -2.0)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = c * (-1.0 / b); else tmp = (b + b) / (a * -2.0); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[(c * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision], N[(N[(b + b), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{-1}{b}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + b}{a \cdot -2}\\
\end{array}
\end{array}
Initial program 71.5%
Simplified71.6%
Taylor expanded in b around -inf 70.2%
Taylor expanded in b around inf 68.1%
Final simplification68.1%
herbie shell --seed 2024087
(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))))