
(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 -6.5e+152)
(/ (- b) a)
(if (<= b 2.4e-45)
(/ (- (sqrt (- (* b b) (* c (* 4.0 a)))) b) (* a 2.0))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -6.5e+152) {
tmp = -b / a;
} else if (b <= 2.4e-45) {
tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - 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 <= (-6.5d+152)) then
tmp = -b / a
else if (b <= 2.4d-45) then
tmp = (sqrt(((b * b) - (c * (4.0d0 * a)))) - 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 <= -6.5e+152) {
tmp = -b / a;
} else if (b <= 2.4e-45) {
tmp = (Math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0);
} else {
tmp = -(c / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -6.5e+152: tmp = -b / a elif b <= 2.4e-45: tmp = (math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0) else: tmp = -(c / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= -6.5e+152) tmp = Float64(Float64(-b) / a); elseif (b <= 2.4e-45) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) - 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 <= -6.5e+152) tmp = -b / a; elseif (b <= 2.4e-45) tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0); else tmp = -(c / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -6.5e+152], N[((-b) / a), $MachinePrecision], If[LessEqual[b, 2.4e-45], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(4.0 * a), $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 -6.5 \cdot 10^{+152}:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{elif}\;b \leq 2.4 \cdot 10^{-45}:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -6.4999999999999997e152Initial program 29.0%
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.f6495.4
Applied rewrites95.4%
if -6.4999999999999997e152 < b < 2.3999999999999999e-45Initial program 83.9%
if 2.3999999999999999e-45 < b Initial program 17.1%
Taylor expanded in c around 0
associate-*r/N/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6487.0
Applied rewrites87.0%
Final simplification86.7%
(FPCore (a b c)
:precision binary64
(if (<= b -2.6e+75)
(fma b (/ c (* b b)) (/ (- b) a))
(if (<= b 2.4e-45)
(* (/ -0.5 a) (- b (sqrt (fma c (* a -4.0) (* b b)))))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -2.6e+75) {
tmp = fma(b, (c / (b * b)), (-b / a));
} else if (b <= 2.4e-45) {
tmp = (-0.5 / a) * (b - sqrt(fma(c, (a * -4.0), (b * b))));
} else {
tmp = -(c / b);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -2.6e+75) tmp = fma(b, Float64(c / Float64(b * b)), Float64(Float64(-b) / a)); elseif (b <= 2.4e-45) tmp = Float64(Float64(-0.5 / a) * Float64(b - sqrt(fma(c, Float64(a * -4.0), Float64(b * b))))); else tmp = Float64(-Float64(c / b)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -2.6e+75], N[(b * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[((-b) / a), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 2.4e-45], N[(N[(-0.5 / a), $MachinePrecision] * N[(b - N[Sqrt[N[(c * N[(a * -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 -2.6 \cdot 10^{+75}:\\
\;\;\;\;\mathsf{fma}\left(b, \frac{c}{b \cdot b}, \frac{-b}{a}\right)\\
\mathbf{elif}\;b \leq 2.4 \cdot 10^{-45}:\\
\;\;\;\;\frac{-0.5}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -2.59999999999999985e75Initial program 54.6%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-rgt-inN/A
distribute-neg-inN/A
*-commutativeN/A
mul-1-negN/A
distribute-rgt-neg-outN/A
remove-double-negN/A
associate-*l/N/A
*-lft-identityN/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.f6497.0
Applied rewrites97.0%
if -2.59999999999999985e75 < b < 2.3999999999999999e-45Initial program 80.7%
Applied rewrites80.4%
if 2.3999999999999999e-45 < b Initial program 17.1%
Taylor expanded in c around 0
associate-*r/N/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6487.0
Applied rewrites87.0%
Final simplification86.5%
(FPCore (a b c)
:precision binary64
(if (<= b -3.6e-58)
(fma b (/ c (* b b)) (/ (- b) a))
(if (<= b 2.4e-45)
(/ (- (sqrt (* a (* c -4.0))) b) (* a 2.0))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -3.6e-58) {
tmp = fma(b, (c / (b * b)), (-b / a));
} else if (b <= 2.4e-45) {
tmp = (sqrt((a * (c * -4.0))) - b) / (a * 2.0);
} else {
tmp = -(c / b);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -3.6e-58) tmp = fma(b, Float64(c / Float64(b * b)), Float64(Float64(-b) / a)); elseif (b <= 2.4e-45) tmp = Float64(Float64(sqrt(Float64(a * Float64(c * -4.0))) - b) / Float64(a * 2.0)); else tmp = Float64(-Float64(c / b)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -3.6e-58], N[(b * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[((-b) / a), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 2.4e-45], N[(N[(N[Sqrt[N[(a * N[(c * -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 -3.6 \cdot 10^{-58}:\\
\;\;\;\;\mathsf{fma}\left(b, \frac{c}{b \cdot b}, \frac{-b}{a}\right)\\
\mathbf{elif}\;b \leq 2.4 \cdot 10^{-45}:\\
\;\;\;\;\frac{\sqrt{a \cdot \left(c \cdot -4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < -3.60000000000000009e-58Initial program 68.5%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-rgt-inN/A
distribute-neg-inN/A
*-commutativeN/A
mul-1-negN/A
distribute-rgt-neg-outN/A
remove-double-negN/A
associate-*l/N/A
*-lft-identityN/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.f6490.2
Applied rewrites90.2%
if -3.60000000000000009e-58 < b < 2.3999999999999999e-45Initial program 74.9%
Taylor expanded in c around inf
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6467.9
Applied rewrites67.9%
if 2.3999999999999999e-45 < b Initial program 17.1%
Taylor expanded in c around 0
associate-*r/N/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6487.0
Applied rewrites87.0%
Final simplification82.4%
(FPCore (a b c)
:precision binary64
(if (<= b -3.6e-58)
(fma b (/ c (* b b)) (/ (- b) a))
(if (<= b 2.4e-45)
(* (/ -0.5 a) (- b (sqrt (* a (* c -4.0)))))
(- (/ c b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -3.6e-58) {
tmp = fma(b, (c / (b * b)), (-b / a));
} else if (b <= 2.4e-45) {
tmp = (-0.5 / a) * (b - sqrt((a * (c * -4.0))));
} else {
tmp = -(c / b);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -3.6e-58) tmp = fma(b, Float64(c / Float64(b * b)), Float64(Float64(-b) / a)); elseif (b <= 2.4e-45) 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
code[a_, b_, c_] := If[LessEqual[b, -3.6e-58], N[(b * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[((-b) / a), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 2.4e-45], 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 -3.6 \cdot 10^{-58}:\\
\;\;\;\;\mathsf{fma}\left(b, \frac{c}{b \cdot b}, \frac{-b}{a}\right)\\
\mathbf{elif}\;b \leq 2.4 \cdot 10^{-45}:\\
\;\;\;\;\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 < -3.60000000000000009e-58Initial program 68.5%
Taylor expanded in b around -inf
mul-1-negN/A
distribute-rgt-inN/A
distribute-neg-inN/A
*-commutativeN/A
mul-1-negN/A
distribute-rgt-neg-outN/A
remove-double-negN/A
associate-*l/N/A
*-lft-identityN/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.f6490.2
Applied rewrites90.2%
if -3.60000000000000009e-58 < b < 2.3999999999999999e-45Initial program 74.9%
Applied rewrites74.7%
Taylor expanded in c around inf
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
associate-*r*N/A
lower-*.f64N/A
unpow2N/A
rem-square-sqrtN/A
lower-*.f6467.7
Applied rewrites67.7%
if 2.3999999999999999e-45 < b Initial program 17.1%
Taylor expanded in c around 0
associate-*r/N/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6487.0
Applied rewrites87.0%
Final simplification82.4%
(FPCore (a b c) :precision binary64 (if (<= b 5e-299) (/ (- b) a) (- (/ c b))))
double code(double a, double b, double c) {
double tmp;
if (b <= 5e-299) {
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 <= 5d-299) 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 <= 5e-299) {
tmp = -b / a;
} else {
tmp = -(c / b);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 5e-299: tmp = -b / a else: tmp = -(c / b) return tmp
function code(a, b, c) tmp = 0.0 if (b <= 5e-299) 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 <= 5e-299) tmp = -b / a; else tmp = -(c / b); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 5e-299], N[((-b) / a), $MachinePrecision], (-N[(c / b), $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 5 \cdot 10^{-299}:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{else}:\\
\;\;\;\;-\frac{c}{b}\\
\end{array}
\end{array}
if b < 4.99999999999999956e-299Initial program 71.8%
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.f6471.1
Applied rewrites71.1%
if 4.99999999999999956e-299 < b Initial program 34.3%
Taylor expanded in c around 0
associate-*r/N/A
lower-/.f64N/A
mul-1-negN/A
lower-neg.f6465.0
Applied rewrites65.0%
Final simplification68.1%
(FPCore (a b c) :precision binary64 (if (<= b 6.5e-13) (/ (- b) a) (/ c b)))
double code(double a, double b, double c) {
double tmp;
if (b <= 6.5e-13) {
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 <= 6.5d-13) 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 <= 6.5e-13) {
tmp = -b / a;
} else {
tmp = c / b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 6.5e-13: tmp = -b / a else: tmp = c / b return tmp
function code(a, b, c) tmp = 0.0 if (b <= 6.5e-13) tmp = Float64(Float64(-b) / a); else tmp = Float64(c / b); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 6.5e-13) tmp = -b / a; else tmp = c / b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 6.5e-13], N[((-b) / a), $MachinePrecision], N[(c / b), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.5 \cdot 10^{-13}:\\
\;\;\;\;\frac{-b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b}\\
\end{array}
\end{array}
if b < 6.49999999999999957e-13Initial program 70.9%
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.f6453.5
Applied rewrites53.5%
if 6.49999999999999957e-13 < b Initial program 15.4%
Applied rewrites8.2%
Taylor expanded in b around -inf
lower-/.f6429.5
Applied rewrites29.5%
Final simplification45.9%
(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 53.4%
Applied rewrites30.4%
Taylor expanded in b around -inf
lower-/.f6411.5
Applied rewrites11.5%
(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 53.4%
Applied rewrites30.4%
Taylor expanded in c around 0
lower-/.f642.7
Applied rewrites2.7%
herbie shell --seed 2024235
(FPCore (a b c)
:name "Quadratic roots, full range"
:precision binary64
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))