
(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 4 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 -2.6e+104)
(if (>= b 0.0) (/ (- c) b) (* -0.5 (/ (* b 2.0) a)))
(if (<= b 5.3e+115)
(if (>= b 0.0) (/ (* c 2.0) (- (- b) t_0)) (/ (- t_0 b) (* 2.0 a)))
(if (>= b 0.0)
(* c (/ -2.0 (+ b (+ b (* -2.0 (* c (/ a b)))))))
(* -0.5 (/ (+ b b) a)))))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -2.6e+104) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = -c / b;
} else {
tmp_2 = -0.5 * ((b * 2.0) / a);
}
tmp_1 = tmp_2;
} else if (b <= 5.3e+115) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c * 2.0) / (-b - t_0);
} else {
tmp_3 = (t_0 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = c * (-2.0 / (b + (b + (-2.0 * (c * (a / b))))));
} else {
tmp_1 = -0.5 * ((b + b) / a);
}
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) :: tmp
real(8) :: tmp_1
real(8) :: tmp_2
real(8) :: tmp_3
t_0 = sqrt(((b * b) - (c * (a * 4.0d0))))
if (b <= (-2.6d+104)) then
if (b >= 0.0d0) then
tmp_2 = -c / b
else
tmp_2 = (-0.5d0) * ((b * 2.0d0) / a)
end if
tmp_1 = tmp_2
else if (b <= 5.3d+115) then
if (b >= 0.0d0) then
tmp_3 = (c * 2.0d0) / (-b - t_0)
else
tmp_3 = (t_0 - b) / (2.0d0 * a)
end if
tmp_1 = tmp_3
else if (b >= 0.0d0) then
tmp_1 = c * ((-2.0d0) / (b + (b + ((-2.0d0) * (c * (a / b))))))
else
tmp_1 = (-0.5d0) * ((b + b) / a)
end if
code = tmp_1
end function
public static double code(double a, double b, double c) {
double t_0 = Math.sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -2.6e+104) {
double tmp_2;
if (b >= 0.0) {
tmp_2 = -c / b;
} else {
tmp_2 = -0.5 * ((b * 2.0) / a);
}
tmp_1 = tmp_2;
} else if (b <= 5.3e+115) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c * 2.0) / (-b - t_0);
} else {
tmp_3 = (t_0 - b) / (2.0 * a);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = c * (-2.0 / (b + (b + (-2.0 * (c * (a / b))))));
} else {
tmp_1 = -0.5 * ((b + b) / a);
}
return tmp_1;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - (c * (a * 4.0)))) tmp_1 = 0 if b <= -2.6e+104: tmp_2 = 0 if b >= 0.0: tmp_2 = -c / b else: tmp_2 = -0.5 * ((b * 2.0) / a) tmp_1 = tmp_2 elif b <= 5.3e+115: tmp_3 = 0 if b >= 0.0: tmp_3 = (c * 2.0) / (-b - t_0) else: tmp_3 = (t_0 - b) / (2.0 * a) tmp_1 = tmp_3 elif b >= 0.0: tmp_1 = c * (-2.0 / (b + (b + (-2.0 * (c * (a / b)))))) else: tmp_1 = -0.5 * ((b + b) / a) 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 <= -2.6e+104) tmp_2 = 0.0 if (b >= 0.0) tmp_2 = Float64(Float64(-c) / b); else tmp_2 = Float64(-0.5 * Float64(Float64(b * 2.0) / a)); end tmp_1 = tmp_2; elseif (b <= 5.3e+115) 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(2.0 * a)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = Float64(c * Float64(-2.0 / Float64(b + Float64(b + Float64(-2.0 * Float64(c * Float64(a / b))))))); else tmp_1 = Float64(-0.5 * Float64(Float64(b + b) / a)); end return tmp_1 end
function tmp_5 = code(a, b, c) t_0 = sqrt(((b * b) - (c * (a * 4.0)))); tmp_2 = 0.0; if (b <= -2.6e+104) tmp_3 = 0.0; if (b >= 0.0) tmp_3 = -c / b; else tmp_3 = -0.5 * ((b * 2.0) / a); end tmp_2 = tmp_3; elseif (b <= 5.3e+115) tmp_4 = 0.0; if (b >= 0.0) tmp_4 = (c * 2.0) / (-b - t_0); else tmp_4 = (t_0 - b) / (2.0 * a); end tmp_2 = tmp_4; elseif (b >= 0.0) tmp_2 = c * (-2.0 / (b + (b + (-2.0 * (c * (a / b)))))); else tmp_2 = -0.5 * ((b + b) / a); end tmp_5 = tmp_2; 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, -2.6e+104], If[GreaterEqual[b, 0.0], N[((-c) / b), $MachinePrecision], N[(-0.5 * N[(N[(b * 2.0), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 5.3e+115], 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[(2.0 * a), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], N[(c * N[(-2.0 / N[(b + N[(b + N[(-2.0 * N[(c * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(-0.5 * N[(N[(b + b), $MachinePrecision] / a), $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 -2.6 \cdot 10^{+104}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-c}{b}\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{b \cdot 2}{a}\\
\end{array}\\
\mathbf{elif}\;b \leq 5.3 \cdot 10^{+115}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{c \cdot 2}{\left(-b\right) - t_0}\\
\mathbf{else}:\\
\;\;\;\;\frac{t_0 - b}{2 \cdot a}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;c \cdot \frac{-2}{b + \left(b + -2 \cdot \left(c \cdot \frac{a}{b}\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{b + b}{a}\\
\end{array}
\end{array}
if b < -2.6e104Initial program 46.8%
Simplified46.9%
Taylor expanded in c around 0 46.9%
mul-1-neg46.9%
distribute-neg-frac46.9%
Simplified46.9%
Taylor expanded in b around -inf 97.0%
*-commutative97.0%
Simplified97.0%
if -2.6e104 < b < 5.29999999999999965e115Initial program 91.2%
if 5.29999999999999965e115 < b Initial program 46.8%
Simplified47.0%
Taylor expanded in b around -inf 47.0%
Taylor expanded in c around 0 87.4%
associate-/l*98.0%
Simplified98.0%
associate-/r/98.0%
Applied egg-rr98.0%
Final simplification94.0%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- c) b) (* -0.5 (+ (* -2.0 (/ c b)) (* 2.0 (/ b a))))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -c / b;
} else {
tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (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 = -c / b
else
tmp = (-0.5d0) * (((-2.0d0) * (c / b)) + (2.0d0 * (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 = -c / b;
} else {
tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a)));
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -c / b else: tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a))) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-c) / b); else tmp = Float64(-0.5 * Float64(Float64(-2.0 * Float64(c / b)) + Float64(2.0 * Float64(b / a)))); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -c / b; else tmp = -0.5 * ((-2.0 * (c / b)) + (2.0 * (b / a))); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-c) / b), $MachinePrecision], N[(-0.5 * N[(N[(-2.0 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(2.0 * N[(b / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-c}{b}\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \left(-2 \cdot \frac{c}{b} + 2 \cdot \frac{b}{a}\right)\\
\end{array}
\end{array}
Initial program 71.2%
Simplified71.2%
Taylor expanded in c around 0 72.5%
mul-1-neg72.5%
distribute-neg-frac72.5%
Simplified72.5%
Taylor expanded in b around -inf 69.3%
Final simplification69.3%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- c) b) (* -0.5 (* -2.0 (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -c / b;
} else {
tmp = -0.5 * (-2.0 * (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 = -c / b
else
tmp = (-0.5d0) * ((-2.0d0) * (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 = -c / b;
} else {
tmp = -0.5 * (-2.0 * (c / b));
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -c / b else: tmp = -0.5 * (-2.0 * (c / b)) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-c) / b); else tmp = Float64(-0.5 * Float64(-2.0 * Float64(c / b))); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -c / b; else tmp = -0.5 * (-2.0 * (c / b)); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-c) / b), $MachinePrecision], N[(-0.5 * N[(-2.0 * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-c}{b}\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \left(-2 \cdot \frac{c}{b}\right)\\
\end{array}
\end{array}
Initial program 71.2%
Simplified71.2%
Taylor expanded in c around 0 72.5%
mul-1-neg72.5%
distribute-neg-frac72.5%
Simplified72.5%
Taylor expanded in b around -inf 66.9%
Taylor expanded in a around inf 35.5%
Final simplification35.5%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (/ (- c) b) (* -0.5 (/ (* b 2.0) a))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -c / b;
} else {
tmp = -0.5 * ((b * 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) :: tmp
if (b >= 0.0d0) then
tmp = -c / b
else
tmp = (-0.5d0) * ((b * 2.0d0) / a)
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 = -0.5 * ((b * 2.0) / a);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -c / b else: tmp = -0.5 * ((b * 2.0) / a) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(Float64(-c) / b); else tmp = Float64(-0.5 * Float64(Float64(b * 2.0) / a)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -c / b; else tmp = -0.5 * ((b * 2.0) / a); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[((-c) / b), $MachinePrecision], N[(-0.5 * N[(N[(b * 2.0), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{-c}{b}\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{b \cdot 2}{a}\\
\end{array}
\end{array}
Initial program 71.2%
Simplified71.2%
Taylor expanded in c around 0 72.5%
mul-1-neg72.5%
distribute-neg-frac72.5%
Simplified72.5%
Taylor expanded in b around -inf 69.0%
*-commutative69.0%
Simplified69.0%
Final simplification69.0%
herbie shell --seed 2023319
(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))))