
(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 3 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 b)))) (t_1 (sqrt (- (* b b) (* c (* a 4.0))))))
(if (<= b -2.4e+156)
(if (>= b 0.0) t_0 (- (/ c b) (/ b a)))
(if (<= b 1.8e+78)
(if (>= b 0.0) (/ (* c 2.0) (- (- b) t_1)) (/ (- t_1 b) (* a 2.0)))
(if (>= b 0.0) t_0 (* (* b 2.0) (/ -0.5 a)))))))
double code(double a, double b, double c) {
double t_0 = -2.0 * (c / (b + b));
double t_1 = sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -2.4e+156) {
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 <= 1.8e+78) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c * 2.0) / (-b - t_1);
} else {
tmp_3 = (t_1 - b) / (a * 2.0);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = (b * 2.0) * (-0.5 / 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) :: t_1
real(8) :: tmp
real(8) :: tmp_1
real(8) :: tmp_2
real(8) :: tmp_3
t_0 = (-2.0d0) * (c / (b + b))
t_1 = sqrt(((b * b) - (c * (a * 4.0d0))))
if (b <= (-2.4d+156)) 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 <= 1.8d+78) then
if (b >= 0.0d0) then
tmp_3 = (c * 2.0d0) / (-b - t_1)
else
tmp_3 = (t_1 - b) / (a * 2.0d0)
end if
tmp_1 = tmp_3
else if (b >= 0.0d0) then
tmp_1 = t_0
else
tmp_1 = (b * 2.0d0) * ((-0.5d0) / a)
end if
code = tmp_1
end function
public static double code(double a, double b, double c) {
double t_0 = -2.0 * (c / (b + b));
double t_1 = Math.sqrt(((b * b) - (c * (a * 4.0))));
double tmp_1;
if (b <= -2.4e+156) {
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 <= 1.8e+78) {
double tmp_3;
if (b >= 0.0) {
tmp_3 = (c * 2.0) / (-b - t_1);
} else {
tmp_3 = (t_1 - b) / (a * 2.0);
}
tmp_1 = tmp_3;
} else if (b >= 0.0) {
tmp_1 = t_0;
} else {
tmp_1 = (b * 2.0) * (-0.5 / a);
}
return tmp_1;
}
def code(a, b, c): t_0 = -2.0 * (c / (b + b)) t_1 = math.sqrt(((b * b) - (c * (a * 4.0)))) tmp_1 = 0 if b <= -2.4e+156: tmp_2 = 0 if b >= 0.0: tmp_2 = t_0 else: tmp_2 = (c / b) - (b / a) tmp_1 = tmp_2 elif b <= 1.8e+78: tmp_3 = 0 if b >= 0.0: tmp_3 = (c * 2.0) / (-b - t_1) else: tmp_3 = (t_1 - b) / (a * 2.0) tmp_1 = tmp_3 elif b >= 0.0: tmp_1 = t_0 else: tmp_1 = (b * 2.0) * (-0.5 / a) return tmp_1
function code(a, b, c) t_0 = Float64(-2.0 * Float64(c / Float64(b + b))) t_1 = sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) tmp_1 = 0.0 if (b <= -2.4e+156) 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 <= 1.8e+78) tmp_3 = 0.0 if (b >= 0.0) tmp_3 = Float64(Float64(c * 2.0) / Float64(Float64(-b) - t_1)); else tmp_3 = Float64(Float64(t_1 - b) / Float64(a * 2.0)); end tmp_1 = tmp_3; elseif (b >= 0.0) tmp_1 = t_0; else tmp_1 = Float64(Float64(b * 2.0) * Float64(-0.5 / a)); end return tmp_1 end
function tmp_5 = code(a, b, c) t_0 = -2.0 * (c / (b + b)); t_1 = sqrt(((b * b) - (c * (a * 4.0)))); tmp_2 = 0.0; if (b <= -2.4e+156) 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 <= 1.8e+78) tmp_4 = 0.0; if (b >= 0.0) tmp_4 = (c * 2.0) / (-b - t_1); else tmp_4 = (t_1 - b) / (a * 2.0); end tmp_2 = tmp_4; elseif (b >= 0.0) tmp_2 = t_0; else tmp_2 = (b * 2.0) * (-0.5 / a); end tmp_5 = tmp_2; end
code[a_, b_, c_] := Block[{t$95$0 = N[(-2.0 * N[(c / N[(b + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[b, -2.4e+156], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]], If[LessEqual[b, 1.8e+78], If[GreaterEqual[b, 0.0], N[(N[(c * 2.0), $MachinePrecision] / N[((-b) - t$95$1), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$1 - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]], If[GreaterEqual[b, 0.0], t$95$0, N[(N[(b * 2.0), $MachinePrecision] * N[(-0.5 / a), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := -2 \cdot \frac{c}{b + b}\\
t_1 := \sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)}\\
\mathbf{if}\;b \leq -2.4 \cdot 10^{+156}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;t_0\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} - \frac{b}{a}\\
\end{array}\\
\mathbf{elif}\;b \leq 1.8 \cdot 10^{+78}:\\
\;\;\;\;\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;\frac{c \cdot 2}{\left(-b\right) - t_1}\\
\mathbf{else}:\\
\;\;\;\;\frac{t_1 - b}{a \cdot 2}\\
\end{array}\\
\mathbf{elif}\;b \geq 0:\\
\;\;\;\;t_0\\
\mathbf{else}:\\
\;\;\;\;\left(b \cdot 2\right) \cdot \frac{-0.5}{a}\\
\end{array}
\end{array}
if b < -2.4000000000000001e156Initial program 37.9%
Simplified37.9%
Taylor expanded in b around inf 37.9%
Taylor expanded in b around -inf 100.0%
mul-1-neg100.0%
unsub-neg100.0%
Simplified100.0%
if -2.4000000000000001e156 < b < 1.8000000000000001e78Initial program 89.8%
if 1.8000000000000001e78 < b Initial program 64.0%
Simplified64.0%
Taylor expanded in b around inf 100.0%
Taylor expanded in b around -inf 100.0%
*-commutative100.0%
Simplified100.0%
Final simplification94.2%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (* -2.0 (/ c (+ b b))) (* (* b 2.0) (/ -0.5 a))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -2.0 * (c / (b + b));
} else {
tmp = (b * 2.0) * (-0.5 / 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 = (-2.0d0) * (c / (b + b))
else
tmp = (b * 2.0d0) * ((-0.5d0) / a)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -2.0 * (c / (b + b));
} else {
tmp = (b * 2.0) * (-0.5 / a);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -2.0 * (c / (b + b)) else: tmp = (b * 2.0) * (-0.5 / a) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(-2.0 * Float64(c / Float64(b + b))); else tmp = Float64(Float64(b * 2.0) * Float64(-0.5 / a)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -2.0 * (c / (b + b)); else tmp = (b * 2.0) * (-0.5 / a); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[(-2.0 * N[(c / N[(b + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(b * 2.0), $MachinePrecision] * N[(-0.5 / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;-2 \cdot \frac{c}{b + b}\\
\mathbf{else}:\\
\;\;\;\;\left(b \cdot 2\right) \cdot \frac{-0.5}{a}\\
\end{array}
\end{array}
Initial program 75.5%
Simplified75.4%
Taylor expanded in b around inf 74.4%
Taylor expanded in b around -inf 69.8%
*-commutative69.8%
Simplified69.8%
Final simplification69.8%
(FPCore (a b c) :precision binary64 (if (>= b 0.0) (* -2.0 (/ c (+ b b))) (- (/ c b) (/ b a))))
double code(double a, double b, double c) {
double tmp;
if (b >= 0.0) {
tmp = -2.0 * (c / (b + b));
} else {
tmp = (c / b) - (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 = (-2.0d0) * (c / (b + b))
else
tmp = (c / b) - (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 = -2.0 * (c / (b + b));
} else {
tmp = (c / b) - (b / a);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b >= 0.0: tmp = -2.0 * (c / (b + b)) else: tmp = (c / b) - (b / a) return tmp
function code(a, b, c) tmp = 0.0 if (b >= 0.0) tmp = Float64(-2.0 * Float64(c / Float64(b + b))); else tmp = Float64(Float64(c / b) - Float64(b / a)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b >= 0.0) tmp = -2.0 * (c / (b + b)); else tmp = (c / b) - (b / a); end tmp_2 = tmp; end
code[a_, b_, c_] := If[GreaterEqual[b, 0.0], N[(-2.0 * N[(c / N[(b + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \geq 0:\\
\;\;\;\;-2 \cdot \frac{c}{b + b}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} - \frac{b}{a}\\
\end{array}
\end{array}
Initial program 75.5%
Simplified75.4%
Taylor expanded in b around inf 74.4%
Taylor expanded in b around -inf 70.1%
mul-1-neg70.1%
unsub-neg70.1%
Simplified70.1%
Final simplification70.1%
herbie shell --seed 2023201
(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))))