
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (-b + sqrt(((b * b) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = (-b + sqrt(((b * b) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}
(FPCore (a b c)
:precision binary64
(if (<= b -5.2e+47)
(fma b (/ c (* b b)) (/ b (- a)))
(if (<= b 4.5e-26)
(/ (- (sqrt (- (* b b) (* c (* a 4.0)))) b) (* a 2.0))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -5.2e+47) {
tmp = fma(b, (c / (b * b)), (b / -a));
} else if (b <= 4.5e-26) {
tmp = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
} else {
tmp = -(c / b);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -5.2e+47) tmp = fma(b, Float64(c / Float64(b * b)), Float64(b / Float64(-a))); elseif (b <= 4.5e-26) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(-Float64(c / b)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -5.2e+47], N[(b * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(b / (-a)), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 4.5e-26], 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], (-N[(c / b), $MachinePrecision])]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -5.2 \cdot 10^{+47}:\\
\;\;\;\;\mathsf{fma}\left(b, \frac{c}{b \cdot b}, \frac{b}{-a}\right)\\
\mathbf{elif}\;b \leq 4.5 \cdot 10^{-26}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -5.20000000000000007e47Initial program 71.1%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-rgt-inN/A
distribute-neg-inN/A
associate-*l/N/A
*-lft-identityN/A
*-commutativeN/A
mul-1-negN/A
distribute-rgt-neg-outN/A
remove-double-negN/A
lower-fma.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f64N/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6498.8
Applied rewrites98.8%
if -5.20000000000000007e47 < b < 4.4999999999999999e-26Initial program 79.8%
if 4.4999999999999999e-26 < b Initial program 13.4%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6490.5
Applied rewrites90.5%
Final simplification88.5%
(FPCore (a b c)
:precision binary64
(if (<= b -5.2e+47)
(fma b (/ c (* b b)) (/ b (- a)))
(if (<= b 4.5e-26)
(* (/ -0.5 a) (- b (sqrt (fma a (* c -4.0) (* b b)))))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -5.2e+47) {
tmp = fma(b, (c / (b * b)), (b / -a));
} else if (b <= 4.5e-26) {
tmp = (-0.5 / a) * (b - sqrt(fma(a, (c * -4.0), (b * b))));
} else {
tmp = -(c / b);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -5.2e+47) tmp = fma(b, Float64(c / Float64(b * b)), Float64(b / Float64(-a))); elseif (b <= 4.5e-26) tmp = Float64(Float64(-0.5 / a) * Float64(b - sqrt(fma(a, Float64(c * -4.0), Float64(b * b))))); else tmp = Float64(-Float64(c / b)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -5.2e+47], N[(b * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(b / (-a)), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 4.5e-26], N[(N[(-0.5 / a), $MachinePrecision] * N[(b - N[Sqrt[N[(a * N[(c * -4.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-N[(c / b), $MachinePrecision])]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -5.2 \cdot 10^{+47}:\\
\;\;\;\;\mathsf{fma}\left(b, \frac{c}{b \cdot b}, \frac{b}{-a}\right)\\
\mathbf{elif}\;b \leq 4.5 \cdot 10^{-26}:\\
\;\;\;\;\frac{-0.5}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(a, c \cdot -4, b \cdot b\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -5.20000000000000007e47Initial program 71.1%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-rgt-inN/A
distribute-neg-inN/A
associate-*l/N/A
*-lft-identityN/A
*-commutativeN/A
mul-1-negN/A
distribute-rgt-neg-outN/A
remove-double-negN/A
lower-fma.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f64N/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6498.8
Applied rewrites98.8%
if -5.20000000000000007e47 < b < 4.4999999999999999e-26Initial program 79.8%
Applied rewrites79.6%
if 4.4999999999999999e-26 < b Initial program 13.4%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6490.5
Applied rewrites90.5%
Final simplification88.4%
(FPCore (a b c)
:precision binary64
(if (<= b -8.6e-115)
(/ b (- a))
(if (<= b 2.8e-65)
(/ (- (sqrt (* c (* a -4.0))) b) (* a 2.0))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -8.6e-115) {
tmp = b / -a;
} else if (b <= 2.8e-65) {
tmp = (sqrt((c * (a * -4.0))) - b) / (a * 2.0);
} 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 <= (-8.6d-115)) then
tmp = b / -a
else if (b <= 2.8d-65) then
tmp = (sqrt((c * (a * (-4.0d0)))) - b) / (a * 2.0d0)
else
tmp = -(c / b)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= -8.6e-115) {
tmp = b / -a;
} else if (b <= 2.8e-65) {
tmp = (Math.sqrt((c * (a * -4.0))) - b) / (a * 2.0);
} else {
tmp = -(c / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -8.6e-115: tmp = b / -a elif b <= 2.8e-65: tmp = (math.sqrt((c * (a * -4.0))) - b) / (a * 2.0) else: tmp = -(c / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= -8.6e-115) tmp = Float64(b / Float64(-a)); elseif (b <= 2.8e-65) tmp = Float64(Float64(sqrt(Float64(c * Float64(a * -4.0))) - b) / Float64(a * 2.0)); else tmp = Float64(-Float64(c / b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -8.6e-115) tmp = b / -a; elseif (b <= 2.8e-65) tmp = (sqrt((c * (a * -4.0))) - b) / (a * 2.0); else tmp = -(c / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -8.6e-115], N[(b / (-a)), $MachinePrecision], If[LessEqual[b, 2.8e-65], N[(N[(N[Sqrt[N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], (-N[(c / b), $MachinePrecision])]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -8.6 \cdot 10^{-115}:\\
\;\;\;\;\frac{b}{-a}\\
\mathbf{elif}\;b \leq 2.8 \cdot 10^{-65}:\\
\;\;\;\;\frac{\sqrt{c \cdot \left(a \cdot -4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -8.6000000000000008e-115Initial program 78.2%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6489.0
Applied rewrites89.0%
if -8.6000000000000008e-115 < b < 2.8e-65Initial program 76.8%
Taylor expanded in b around 0
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6472.6
Applied rewrites72.6%
lift-neg.f64N/A
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-+.f64N/A
lift-*.f64N/A
lift-/.f6472.6
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6472.6
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
associate-*l*N/A
lower-*.f64N/A
lower-*.f6472.6
lift-*.f64N/A
*-commutativeN/A
lower-*.f6472.6
Applied rewrites72.6%
if 2.8e-65 < b Initial program 17.8%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6485.4
Applied rewrites85.4%
Final simplification83.8%
(FPCore (a b c)
:precision binary64
(if (<= b -8.6e-115)
(/ b (- a))
(if (<= b 2.8e-65)
(* (/ -0.5 a) (- b (sqrt (* a (* c -4.0)))))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -8.6e-115) {
tmp = b / -a;
} else if (b <= 2.8e-65) {
tmp = (-0.5 / a) * (b - sqrt((a * (c * -4.0))));
} 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 <= (-8.6d-115)) then
tmp = b / -a
else if (b <= 2.8d-65) then
tmp = ((-0.5d0) / a) * (b - sqrt((a * (c * (-4.0d0)))))
else
tmp = -(c / b)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= -8.6e-115) {
tmp = b / -a;
} else if (b <= 2.8e-65) {
tmp = (-0.5 / a) * (b - Math.sqrt((a * (c * -4.0))));
} else {
tmp = -(c / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -8.6e-115: tmp = b / -a elif b <= 2.8e-65: tmp = (-0.5 / a) * (b - math.sqrt((a * (c * -4.0)))) else: tmp = -(c / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= -8.6e-115) tmp = Float64(b / Float64(-a)); elseif (b <= 2.8e-65) tmp = Float64(Float64(-0.5 / a) * Float64(b - sqrt(Float64(a * Float64(c * -4.0))))); else tmp = Float64(-Float64(c / b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -8.6e-115) tmp = b / -a; elseif (b <= 2.8e-65) tmp = (-0.5 / a) * (b - sqrt((a * (c * -4.0)))); else tmp = -(c / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -8.6e-115], N[(b / (-a)), $MachinePrecision], If[LessEqual[b, 2.8e-65], N[(N[(-0.5 / a), $MachinePrecision] * N[(b - N[Sqrt[N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-N[(c / b), $MachinePrecision])]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -8.6 \cdot 10^{-115}:\\
\;\;\;\;\frac{b}{-a}\\
\mathbf{elif}\;b \leq 2.8 \cdot 10^{-65}:\\
\;\;\;\;\frac{-0.5}{a} \cdot \left(b - \sqrt{a \cdot \left(c \cdot -4\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -8.6000000000000008e-115Initial program 78.2%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6489.0
Applied rewrites89.0%
if -8.6000000000000008e-115 < b < 2.8e-65Initial program 76.8%
Applied rewrites76.7%
Taylor expanded in a around inf
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
associate-*r*N/A
*-commutativeN/A
unpow2N/A
rem-square-sqrtN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6472.5
Applied rewrites72.5%
if 2.8e-65 < b Initial program 17.8%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6485.4
Applied rewrites85.4%
Final simplification83.8%
(FPCore (a b c) :precision binary64 (if (<= b -2e-311) (/ b (- a)) (- (/ c b))))
double code(double a, double b, double c) {
double tmp;
if (b <= -2e-311) {
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 <= (-2d-311)) 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 <= -2e-311) {
tmp = b / -a;
} else {
tmp = -(c / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -2e-311: tmp = b / -a else: tmp = -(c / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= -2e-311) tmp = Float64(b / Float64(-a)); else tmp = Float64(-Float64(c / b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -2e-311) tmp = b / -a; else tmp = -(c / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -2e-311], N[(b / (-a)), $MachinePrecision], (-N[(c / b), $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -2 \cdot 10^{-311}:\\
\;\;\;\;\frac{b}{-a}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -1.9999999999999e-311Initial program 79.1%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6472.8
Applied rewrites72.8%
if -1.9999999999999e-311 < b Initial program 32.3%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6467.0
Applied rewrites67.0%
Final simplification70.2%
(FPCore (a b c) :precision binary64 (if (<= b 2300.0) (/ b (- a)) (/ c b)))
double code(double a, double b, double c) {
double tmp;
if (b <= 2300.0) {
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 <= 2300.0d0) 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 <= 2300.0) {
tmp = b / -a;
} else {
tmp = c / b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 2300.0: tmp = b / -a else: tmp = c / b return tmp
function code(a, b, c) tmp = 0.0 if (b <= 2300.0) tmp = Float64(b / Float64(-a)); else tmp = Float64(c / b); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 2300.0) tmp = b / -a; else tmp = c / b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 2300.0], N[(b / (-a)), $MachinePrecision], N[(c / b), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2300:\\
\;\;\;\;\frac{b}{-a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b}\\
\end{array}
\end{array}
if b < 2300Initial program 74.4%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-neg-frac2N/A
mul-1-negN/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6455.4
Applied rewrites55.4%
if 2300 < b Initial program 12.8%
Applied rewrites3.7%
Taylor expanded in b around -inf
lower-/.f6430.3
Applied rewrites30.3%
(FPCore (a b c) :precision binary64 (/ c b))
double code(double a, double b, double c) {
return c / b;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = c / b
end function
public static double code(double a, double b, double c) {
return c / b;
}
def code(a, b, c): return c / b
function code(a, b, c) return Float64(c / b) end
function tmp = code(a, b, c) tmp = c / b; end
code[a_, b_, c_] := N[(c / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c}{b}
\end{array}
Initial program 58.0%
Applied rewrites34.8%
Taylor expanded in b around -inf
lower-/.f6410.3
Applied rewrites10.3%
(FPCore (a b c) :precision binary64 (/ b a))
double code(double a, double b, double c) {
return b / a;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = b / a
end function
public static double code(double a, double b, double c) {
return b / a;
}
def code(a, b, c): return b / a
function code(a, b, c) return Float64(b / a) end
function tmp = code(a, b, c) tmp = b / a; end
code[a_, b_, c_] := N[(b / a), $MachinePrecision]
\begin{array}{l}
\\
\frac{b}{a}
\end{array}
Initial program 58.0%
Applied rewrites34.8%
Taylor expanded in b around inf
lower-/.f642.2
Applied rewrites2.2%
herbie shell --seed 2024219
(FPCore (a b c)
:name "Quadratic roots, full range"
:precision binary64
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))