
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c) :precision binary64 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c): return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c) return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a)) end
function tmp = code(a, b, c) tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a); end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}
(FPCore (a b c)
:precision binary64
(if (<= b -1.2e+152)
(/ (* -2.0 (/ b a)) 3.0)
(if (<= b 5.5e-53)
(/ (+ (- b) (sqrt (fma (* -3.0 a) c (* b b)))) (* 3.0 a))
(* (/ c b) -0.5))))
double code(double a, double b, double c) {
double tmp;
if (b <= -1.2e+152) {
tmp = (-2.0 * (b / a)) / 3.0;
} else if (b <= 5.5e-53) {
tmp = (-b + sqrt(fma((-3.0 * a), c, (b * b)))) / (3.0 * a);
} else {
tmp = (c / b) * -0.5;
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -1.2e+152) tmp = Float64(Float64(-2.0 * Float64(b / a)) / 3.0); elseif (b <= 5.5e-53) tmp = Float64(Float64(Float64(-b) + sqrt(fma(Float64(-3.0 * a), c, Float64(b * b)))) / Float64(3.0 * a)); else tmp = Float64(Float64(c / b) * -0.5); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -1.2e+152], N[(N[(-2.0 * N[(b / a), $MachinePrecision]), $MachinePrecision] / 3.0), $MachinePrecision], If[LessEqual[b, 5.5e-53], N[(N[((-b) + N[Sqrt[N[(N[(-3.0 * a), $MachinePrecision] * c + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.2 \cdot 10^{+152}:\\
\;\;\;\;\frac{-2 \cdot \frac{b}{a}}{3}\\
\mathbf{elif}\;b \leq 5.5 \cdot 10^{-53}:\\
\;\;\;\;\frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(-3 \cdot a, c, b \cdot b\right)}}{3 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} \cdot -0.5\\
\end{array}
\end{array}
if b < -1.2e152Initial program 42.2%
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
metadata-eval42.2
Applied rewrites42.2%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6442.2
lift-+.f64N/A
+-commutativeN/A
lower-+.f6442.2
lift-fma.f64N/A
*-commutativeN/A
lower-fma.f6442.2
lift-*.f64N/A
*-commutativeN/A
lower-*.f6442.2
Applied rewrites42.2%
Taylor expanded in b around -inf
lower-*.f64N/A
lower-/.f6499.9
Applied rewrites99.9%
if -1.2e152 < b < 5.50000000000000023e-53Initial program 73.9%
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
metadata-eval73.9
Applied rewrites73.9%
if 5.50000000000000023e-53 < b Initial program 15.5%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6490.5
Applied rewrites90.5%
(FPCore (a b c)
:precision binary64
(if (<= b -3.8e-40)
(/ (* -2.0 (/ b a)) 3.0)
(if (<= b 5.5e-53)
(/ (+ (- b) (sqrt (* (* c a) -3.0))) (* 3.0 a))
(* (/ c b) -0.5))))
double code(double a, double b, double c) {
double tmp;
if (b <= -3.8e-40) {
tmp = (-2.0 * (b / a)) / 3.0;
} else if (b <= 5.5e-53) {
tmp = (-b + sqrt(((c * a) * -3.0))) / (3.0 * a);
} else {
tmp = (c / b) * -0.5;
}
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 <= (-3.8d-40)) then
tmp = ((-2.0d0) * (b / a)) / 3.0d0
else if (b <= 5.5d-53) then
tmp = (-b + sqrt(((c * a) * (-3.0d0)))) / (3.0d0 * a)
else
tmp = (c / b) * (-0.5d0)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= -3.8e-40) {
tmp = (-2.0 * (b / a)) / 3.0;
} else if (b <= 5.5e-53) {
tmp = (-b + Math.sqrt(((c * a) * -3.0))) / (3.0 * a);
} else {
tmp = (c / b) * -0.5;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -3.8e-40: tmp = (-2.0 * (b / a)) / 3.0 elif b <= 5.5e-53: tmp = (-b + math.sqrt(((c * a) * -3.0))) / (3.0 * a) else: tmp = (c / b) * -0.5 return tmp
function code(a, b, c) tmp = 0.0 if (b <= -3.8e-40) tmp = Float64(Float64(-2.0 * Float64(b / a)) / 3.0); elseif (b <= 5.5e-53) tmp = Float64(Float64(Float64(-b) + sqrt(Float64(Float64(c * a) * -3.0))) / Float64(3.0 * a)); else tmp = Float64(Float64(c / b) * -0.5); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -3.8e-40) tmp = (-2.0 * (b / a)) / 3.0; elseif (b <= 5.5e-53) tmp = (-b + sqrt(((c * a) * -3.0))) / (3.0 * a); else tmp = (c / b) * -0.5; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -3.8e-40], N[(N[(-2.0 * N[(b / a), $MachinePrecision]), $MachinePrecision] / 3.0), $MachinePrecision], If[LessEqual[b, 5.5e-53], N[(N[((-b) + N[Sqrt[N[(N[(c * a), $MachinePrecision] * -3.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -3.8 \cdot 10^{-40}:\\
\;\;\;\;\frac{-2 \cdot \frac{b}{a}}{3}\\
\mathbf{elif}\;b \leq 5.5 \cdot 10^{-53}:\\
\;\;\;\;\frac{\left(-b\right) + \sqrt{\left(c \cdot a\right) \cdot -3}}{3 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} \cdot -0.5\\
\end{array}
\end{array}
if b < -3.7999999999999999e-40Initial program 62.4%
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
metadata-eval62.4
Applied rewrites62.4%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6462.4
lift-+.f64N/A
+-commutativeN/A
lower-+.f6462.4
lift-fma.f64N/A
*-commutativeN/A
lower-fma.f6462.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6462.4
Applied rewrites62.4%
Taylor expanded in b around -inf
lower-*.f64N/A
lower-/.f6482.0
Applied rewrites82.0%
if -3.7999999999999999e-40 < b < 5.50000000000000023e-53Initial program 72.3%
Taylor expanded in a around inf
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6467.4
Applied rewrites67.4%
if 5.50000000000000023e-53 < b Initial program 15.5%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6490.5
Applied rewrites90.5%
(FPCore (a b c) :precision binary64 (if (<= b 2.1e-303) (/ (* -2.0 b) (* 3.0 a)) (* (/ c b) -0.5)))
double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = (-2.0 * b) / (3.0 * a);
} else {
tmp = (c / b) * -0.5;
}
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 <= 2.1d-303) then
tmp = ((-2.0d0) * b) / (3.0d0 * a)
else
tmp = (c / b) * (-0.5d0)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = (-2.0 * b) / (3.0 * a);
} else {
tmp = (c / b) * -0.5;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 2.1e-303: tmp = (-2.0 * b) / (3.0 * a) else: tmp = (c / b) * -0.5 return tmp
function code(a, b, c) tmp = 0.0 if (b <= 2.1e-303) tmp = Float64(Float64(-2.0 * b) / Float64(3.0 * a)); else tmp = Float64(Float64(c / b) * -0.5); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 2.1e-303) tmp = (-2.0 * b) / (3.0 * a); else tmp = (c / b) * -0.5; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 2.1e-303], N[(N[(-2.0 * b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] * -0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.1 \cdot 10^{-303}:\\
\;\;\;\;\frac{-2 \cdot b}{3 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} \cdot -0.5\\
\end{array}
\end{array}
if b < 2.1e-303Initial program 68.5%
Taylor expanded in b around -inf
lower-*.f6454.7
Applied rewrites54.7%
if 2.1e-303 < b Initial program 30.9%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6470.9
Applied rewrites70.9%
(FPCore (a b c) :precision binary64 (if (<= b 2.1e-303) (/ (* -0.6666666666666666 b) a) (* (/ c b) -0.5)))
double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = (-0.6666666666666666 * b) / a;
} else {
tmp = (c / b) * -0.5;
}
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 <= 2.1d-303) then
tmp = ((-0.6666666666666666d0) * b) / a
else
tmp = (c / b) * (-0.5d0)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = (-0.6666666666666666 * b) / a;
} else {
tmp = (c / b) * -0.5;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 2.1e-303: tmp = (-0.6666666666666666 * b) / a else: tmp = (c / b) * -0.5 return tmp
function code(a, b, c) tmp = 0.0 if (b <= 2.1e-303) tmp = Float64(Float64(-0.6666666666666666 * b) / a); else tmp = Float64(Float64(c / b) * -0.5); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 2.1e-303) tmp = (-0.6666666666666666 * b) / a; else tmp = (c / b) * -0.5; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 2.1e-303], N[(N[(-0.6666666666666666 * b), $MachinePrecision] / a), $MachinePrecision], N[(N[(c / b), $MachinePrecision] * -0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.1 \cdot 10^{-303}:\\
\;\;\;\;\frac{-0.6666666666666666 \cdot b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} \cdot -0.5\\
\end{array}
\end{array}
if b < 2.1e-303Initial program 68.5%
Applied rewrites35.7%
Taylor expanded in b around -inf
lower-*.f6454.6
Applied rewrites54.6%
if 2.1e-303 < b Initial program 30.9%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6470.9
Applied rewrites70.9%
(FPCore (a b c) :precision binary64 (if (<= b 2.1e-303) (* -0.6666666666666666 (/ b a)) (* (/ c b) -0.5)))
double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = -0.6666666666666666 * (b / a);
} else {
tmp = (c / b) * -0.5;
}
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 <= 2.1d-303) then
tmp = (-0.6666666666666666d0) * (b / a)
else
tmp = (c / b) * (-0.5d0)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = -0.6666666666666666 * (b / a);
} else {
tmp = (c / b) * -0.5;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 2.1e-303: tmp = -0.6666666666666666 * (b / a) else: tmp = (c / b) * -0.5 return tmp
function code(a, b, c) tmp = 0.0 if (b <= 2.1e-303) tmp = Float64(-0.6666666666666666 * Float64(b / a)); else tmp = Float64(Float64(c / b) * -0.5); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 2.1e-303) tmp = -0.6666666666666666 * (b / a); else tmp = (c / b) * -0.5; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 2.1e-303], N[(-0.6666666666666666 * N[(b / a), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] * -0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.1 \cdot 10^{-303}:\\
\;\;\;\;-0.6666666666666666 \cdot \frac{b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b} \cdot -0.5\\
\end{array}
\end{array}
if b < 2.1e-303Initial program 68.5%
Taylor expanded in b around -inf
lower-*.f64N/A
lower-/.f6454.6
Applied rewrites54.6%
if 2.1e-303 < b Initial program 30.9%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6470.9
Applied rewrites70.9%
(FPCore (a b c) :precision binary64 (if (<= b 2.1e-303) (* -0.6666666666666666 (/ b a)) (* c (/ -0.5 b))))
double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = -0.6666666666666666 * (b / a);
} else {
tmp = c * (-0.5 / 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 <= 2.1d-303) then
tmp = (-0.6666666666666666d0) * (b / a)
else
tmp = c * ((-0.5d0) / b)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 2.1e-303) {
tmp = -0.6666666666666666 * (b / a);
} else {
tmp = c * (-0.5 / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 2.1e-303: tmp = -0.6666666666666666 * (b / a) else: tmp = c * (-0.5 / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= 2.1e-303) tmp = Float64(-0.6666666666666666 * Float64(b / a)); else tmp = Float64(c * Float64(-0.5 / b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 2.1e-303) tmp = -0.6666666666666666 * (b / a); else tmp = c * (-0.5 / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 2.1e-303], N[(-0.6666666666666666 * N[(b / a), $MachinePrecision]), $MachinePrecision], N[(c * N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.1 \cdot 10^{-303}:\\
\;\;\;\;-0.6666666666666666 \cdot \frac{b}{a}\\
\mathbf{else}:\\
\;\;\;\;c \cdot \frac{-0.5}{b}\\
\end{array}
\end{array}
if b < 2.1e-303Initial program 68.5%
Taylor expanded in b around -inf
lower-*.f64N/A
lower-/.f6454.6
Applied rewrites54.6%
if 2.1e-303 < b Initial program 30.9%
Taylor expanded in a around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f6470.9
Applied rewrites70.9%
Applied rewrites70.6%
(FPCore (a b c) :precision binary64 (* -0.6666666666666666 (/ b a)))
double code(double a, double b, double c) {
return -0.6666666666666666 * (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 = (-0.6666666666666666d0) * (b / a)
end function
public static double code(double a, double b, double c) {
return -0.6666666666666666 * (b / a);
}
def code(a, b, c): return -0.6666666666666666 * (b / a)
function code(a, b, c) return Float64(-0.6666666666666666 * Float64(b / a)) end
function tmp = code(a, b, c) tmp = -0.6666666666666666 * (b / a); end
code[a_, b_, c_] := N[(-0.6666666666666666 * N[(b / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.6666666666666666 \cdot \frac{b}{a}
\end{array}
Initial program 48.1%
Taylor expanded in b around -inf
lower-*.f64N/A
lower-/.f6426.2
Applied rewrites26.2%
herbie shell --seed 2024342
(FPCore (a b c)
:name "Cubic critical"
:precision binary64
(/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))