
(FPCore (a b c) :precision binary64 (let* ((t_0 (sqrt (- (* b b) (* (* 4.0 a) c))))) (if (>= b 0.0) (/ (- (- b) t_0) (* 2.0 a)) (/ (* 2.0 c) (+ (- b) t_0)))))
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 = (-b - t_0) / (2.0 * a);
} else {
tmp = (2.0 * c) / (-b + t_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) :: t_0
real(8) :: tmp
t_0 = sqrt(((b * b) - ((4.0d0 * a) * c)))
if (b >= 0.0d0) then
tmp = (-b - t_0) / (2.0d0 * a)
else
tmp = (2.0d0 * c) / (-b + t_0)
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 = (-b - t_0) / (2.0 * a);
} else {
tmp = (2.0 * c) / (-b + t_0);
}
return tmp;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - ((4.0 * a) * c))) tmp = 0 if b >= 0.0: tmp = (-b - t_0) / (2.0 * a) else: tmp = (2.0 * c) / (-b + t_0) 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(Float64(-b) - t_0) / Float64(2.0 * a)); else tmp = Float64(Float64(2.0 * c) / Float64(Float64(-b) + t_0)); 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 = (-b - t_0) / (2.0 * a); else tmp = (2.0 * c) / (-b + t_0); 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[((-b) - t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) + t$95$0), $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{\left(-b\right) - t_0}{2 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) + t_0}\\
\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) (/ (- (- b) t_0) (* 2.0 a)) (/ (* 2.0 c) (+ (- b) t_0)))))
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 = (-b - t_0) / (2.0 * a);
} else {
tmp = (2.0 * c) / (-b + t_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) :: t_0
real(8) :: tmp
t_0 = sqrt(((b * b) - ((4.0d0 * a) * c)))
if (b >= 0.0d0) then
tmp = (-b - t_0) / (2.0d0 * a)
else
tmp = (2.0d0 * c) / (-b + t_0)
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 = (-b - t_0) / (2.0 * a);
} else {
tmp = (2.0 * c) / (-b + t_0);
}
return tmp;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - ((4.0 * a) * c))) tmp = 0 if b >= 0.0: tmp = (-b - t_0) / (2.0 * a) else: tmp = (2.0 * c) / (-b + t_0) 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(Float64(-b) - t_0) / Float64(2.0 * a)); else tmp = Float64(Float64(2.0 * c) / Float64(Float64(-b) + t_0)); 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 = (-b - t_0) / (2.0 * a); else tmp = (2.0 * c) / (-b + t_0); 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[((-b) - t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(2.0 * c), $MachinePrecision] / N[((-b) + t$95$0), $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{\left(-b\right) - t_0}{2 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{\left(-b\right) + t_0}\\
\end{array}
\end{array}
(FPCore (a b c)
:precision binary64
(let* ((t_0 (sqrt (- (* b b) (* c (* a 4.0))))))
(if (<= b -6e+154)
(if (>= b 0.0)
(/ (- b) a)
(/ (* 2.0 c) (fma -2.0 b (* 2.0 (* a (/ c b))))))
(if (<= b 9.2e+105)
(if (>= b 0.0) (/ (- (- b) t_0) (* a 2.0)) (/ (* 2.0 c) (- t_0 b)))
(if (>= b 0.0)
(* -0.5 (+ (* -2.0 (/ c b)) (* 2.0 (/ b a))))
(* c (/ 2.0 (- (- b) b))))))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -6e+154) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = -b / a;
} else {
tmp_2 = (2.0 * c) / fma(-2.0, b, (2.0 * (a * (c / b))));
}
tmp_1 = tmp_2;
} else if (b <= 9.2e+105) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (-b - t_0) / (a * 2.0);
} else {
tmp_3 = (2.0 * c) / (t_0 - b);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a)));
} else {
tmp_1 = c * (2.0 / (-b - b));
}
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 <= -6e+154) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = Float64(Float64(-b) / a); else tmp_2 = Float64(Float64(2.0 * c) / fma(-2.0, b, Float64(2.0 * Float64(a * Float64(c / b))))); end tmp_1 = tmp_2; elseif (b <= 9.2e+105) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(Float64(-b) - t_0) / Float64(a * 2.0)); else tmp_3 = Float64(Float64(2.0 * c) / Float64(t_0 - b)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = Float64(-0.5 * Float64(Float64(-2.0 * Float64(c / b)) + Float64(2.0 * Float64(b / a)))); else tmp_1 = Float64(c * Float64(2.0 / Float64(Float64(-b) - b))); 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, -6e+154], If[GreaterEqual[b, 0.0], N[((-b) / a), $MachinePrecision], N[(N[(2.0 * c), $MachinePrecision] / N[(-2.0 * b + N[(2.0 * N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 9.2e+105], If[GreaterEqual[b, 0.0], N[(N[((-b) - t$95$0), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(2.0 * c), $MachinePrecision] / N[(t$95$0 - b), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(-0.5 * N[(N[(-2.0 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(2.0 * N[(b / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(c * N[(2.0 / N[((-b) - b), $MachinePrecision]), $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 -6 \cdot 10^{+154}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{\mathsf{fma}\left(-2, b, 2 \cdot \left(a \cdot \frac{c}{b}\right)\right)}\\
\end{array}\\
\mathbf{elif}\;b \leq 9.2 \cdot 10^{+105}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{\left(-b\right) - t_0}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{t_0 - b}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;-0.5 \cdot \left(-2 \cdot \frac{c}{b} + 2 \cdot \frac{b}{a}\right)\\
\mathbf{else}:\\
\;\;\;\;c \cdot \frac{2}{\left(-b\right) - b}\\
\end{array}
\end{array}
if b < -6.00000000000000052e154Initial program 39.3%
Taylor expanded in b around inf 39.3%
associate-*r/39.3%
mul-1-neg39.3%
Simplified39.3%
Taylor expanded in b around -inf 88.2%
fma-def88.2%
associate-*r/97.0%
Simplified97.0%
if -6.00000000000000052e154 < b < 9.1999999999999991e105Initial program 86.4%
if 9.1999999999999991e105 < b Initial program 51.6%
Simplified51.6%
Taylor expanded in b around -inf 51.6%
Taylor expanded in b around inf 96.0%
Final simplification90.6%
(FPCore (a b c)
:precision binary64
(let* ((t_0 (/ (- b) a)))
(if (<= b -6e+154)
(if (>= b 0.0) t_0 (/ (* 2.0 c) (fma -2.0 b (* 2.0 (* a (/ c b))))))
(if (>= b 0.0)
t_0
(/ (* 2.0 c) (- (sqrt (- (* b b) (* c (* a 4.0)))) b))))))
double code(double a, double b, double c) {
double t_0 = -b / a;
double tmp_1;
if (b <= -6e+154) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = t_0;
} else {
tmp_2 = (2.0 * c) / fma(-2.0, b, (2.0 * (a * (c / b))));
}
tmp_1 = tmp_2;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = (2.0 * c) / (sqrt(((b * b) - (c * (a * 4.0)))) - b);
}
return tmp_1;
}
function code(a, b, c) t_0 = Float64(Float64(-b) / a) tmp_1 = 0.0 if (b <= -6e+154) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = t_0; else tmp_2 = Float64(Float64(2.0 * c) / fma(-2.0, b, Float64(2.0 * Float64(a * Float64(c / b))))); end tmp_1 = tmp_2; elseif (b >= 0.0) tmp_1 = t_0; else tmp_1 = Float64(Float64(2.0 * c) / Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) - b)); end return tmp_1 end
code[a_, b_, c_] := Block[{t$95$0 = N[((-b) / a), $MachinePrecision]}, If[LessEqual[b, -6e+154], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(2.0 * c), $MachinePrecision] / N[(-2.0 * b + N[(2.0 * N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(2.0 * c), $MachinePrecision] / N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{-b}{a}\\
\mathbf{if}\;b \leq -6 \cdot 10^{+154}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t_0\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{\mathsf{fma}\left(-2, b, 2 \cdot \left(a \cdot \frac{c}{b}\right)\right)}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;t_0\\
\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot c}{\sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)} - b}\\
\end{array}
\end{array}
if b < -6.00000000000000052e154Initial program 39.3%
Taylor expanded in b around inf 39.3%
associate-*r/39.3%
mul-1-neg39.3%
Simplified39.3%
Taylor expanded in b around -inf 88.2%
fma-def88.2%
associate-*r/97.0%
Simplified97.0%
if -6.00000000000000052e154 < b Initial program 76.5%
Taylor expanded in b around inf 73.8%
associate-*r/73.8%
mul-1-neg73.8%
Simplified73.8%
Final simplification78.2%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (* -0.5 (+ (* -2.0 (/ c b)) (* 2.0 (/ b a)))) (* c (/ 2.0 (- (- b) b)))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a)));
} else {
tmp = c * (2.0 / (-b - b));
}
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 = (-0.5d0) * (((-2.0d0) * (c / b)) + (2.0d0 * (b / a)))
else
tmp = c * (2.0d0 / (-b - b))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a)));
} else {
tmp = c * (2.0 / (-b - b));
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a))) else: tmp = c * (2.0 / (-b - b)) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(-0.5 * Float64(Float64(-2.0 * Float64(c / b)) + Float64(2.0 * Float64(b / a)))); else tmp = Float64(c * Float64(2.0 / Float64(Float64(-b) - b))); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a))); else tmp = c * (2.0 / (-b - b)); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[(-0.5 * N[(N[(-2.0 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(2.0 * N[(b / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(c * N[(2.0 / N[((-b) - b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;-0.5 \cdot \left(-2 \cdot \frac{c}{b} + 2 \cdot \frac{b}{a}\right)\\
\mathbf{else}:\\
\;\;\;\;c \cdot \frac{2}{\left(-b\right) - b}\\
\end{array}
\end{array}
Initial program 69.4%
Simplified69.3%
Taylor expanded in b around -inf 69.7%
Taylor expanded in b around inf 67.7%
Final simplification67.7%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- b) a) (/ b a)))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -b / a;
} else {
tmp = b / 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) :: tmp
if (b >= 0.0d0) then
tmp = -b / a
else
tmp = b / a
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -b / a;
} else {
tmp = b / a;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -b / a else: tmp = b / a return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-b) / a); else tmp = Float64(b / a); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -b / a; else tmp = b / a; end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-b) / a), $MachinePrecision], N[(b / a), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{b}{a}\\
\end{array}
\end{array}
Initial program 69.4%
Taylor expanded in b around inf 67.2%
associate-*r/67.2%
mul-1-neg67.2%
Simplified67.2%
Taylor expanded in b around -inf 65.9%
fma-def65.9%
associate-*r/67.5%
Simplified67.5%
Taylor expanded in c around inf 35.9%
Final simplification35.9%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- b) a) (/ (- c) b)))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -b / a;
} else {
tmp = -c / b;
}
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 = -b / a
else
tmp = -c / b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -b / a;
} else {
tmp = -c / b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -b / a else: tmp = -c / b return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-b) / a); else tmp = Float64(Float64(-c) / b); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -b / a; else tmp = -c / b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-b) / a), $MachinePrecision], N[((-c) / b), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{-c}{b}\\
\end{array}
\end{array}
Initial program 69.4%
Taylor expanded in b around inf 67.2%
associate-*r/67.2%
mul-1-neg67.2%
Simplified67.2%
Taylor expanded in b around -inf 67.5%
associate-*r/67.5%
neg-mul-167.5%
Simplified67.5%
Final simplification67.5%
herbie shell --seed 2023301
(FPCore (a b c)
:name "jeff quadratic root 1"
:precision binary64
(if (>= b 0.0) (/ (- (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)) (/ (* 2.0 c) (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))))))