
(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 9 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
(/
(fma
-2.0
(/ (* c (* a (* a (* c c)))) (* (* b b) (* b b)))
(-
(* -0.25 (* (* (pow a 4.0) (pow c 4.0)) (/ 20.0 (* a (pow b 6.0)))))
(fma (* c c) (/ a (* b b)) c)))
b))
double code(double a, double b, double c) {
return fma(-2.0, ((c * (a * (a * (c * c)))) / ((b * b) * (b * b))), ((-0.25 * ((pow(a, 4.0) * pow(c, 4.0)) * (20.0 / (a * pow(b, 6.0))))) - fma((c * c), (a / (b * b)), c))) / b;
}
function code(a, b, c) return Float64(fma(-2.0, Float64(Float64(c * Float64(a * Float64(a * Float64(c * c)))) / Float64(Float64(b * b) * Float64(b * b))), Float64(Float64(-0.25 * Float64(Float64((a ^ 4.0) * (c ^ 4.0)) * Float64(20.0 / Float64(a * (b ^ 6.0))))) - fma(Float64(c * c), Float64(a / Float64(b * b)), c))) / b) end
code[a_, b_, c_] := N[(N[(-2.0 * N[(N[(c * N[(a * N[(a * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(b * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.25 * N[(N[(N[Power[a, 4.0], $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision] * N[(20.0 / N[(a * N[Power[b, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(c * c), $MachinePrecision] * N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision] + c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-2, \frac{c \cdot \left(a \cdot \left(a \cdot \left(c \cdot c\right)\right)\right)}{\left(b \cdot b\right) \cdot \left(b \cdot b\right)}, -0.25 \cdot \left(\left({a}^{4} \cdot {c}^{4}\right) \cdot \frac{20}{a \cdot {b}^{6}}\right) - \mathsf{fma}\left(c \cdot c, \frac{a}{b \cdot b}, c\right)\right)}{b}
\end{array}
Initial program 17.4%
Taylor expanded in b around inf
Applied rewrites97.6%
(FPCore (a b c)
:precision binary64
(/
(fma
(*
(* c (* c (* a (* a (* a a)))))
(/ (* c c) (* (* b (* b a)) (* b (* b (* b b))))))
-5.0
(- (/ (* (* c c) (fma -2.0 (/ (* c (* a a)) (* b b)) (- a))) (* b b)) c))
b))
double code(double a, double b, double c) {
return fma(((c * (c * (a * (a * (a * a))))) * ((c * c) / ((b * (b * a)) * (b * (b * (b * b)))))), -5.0, ((((c * c) * fma(-2.0, ((c * (a * a)) / (b * b)), -a)) / (b * b)) - c)) / b;
}
function code(a, b, c) return Float64(fma(Float64(Float64(c * Float64(c * Float64(a * Float64(a * Float64(a * a))))) * Float64(Float64(c * c) / Float64(Float64(b * Float64(b * a)) * Float64(b * Float64(b * Float64(b * b)))))), -5.0, Float64(Float64(Float64(Float64(c * c) * fma(-2.0, Float64(Float64(c * Float64(a * a)) / Float64(b * b)), Float64(-a))) / Float64(b * b)) - c)) / b) end
code[a_, b_, c_] := N[(N[(N[(N[(c * N[(c * N[(a * N[(a * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(c * c), $MachinePrecision] / N[(N[(b * N[(b * a), $MachinePrecision]), $MachinePrecision] * N[(b * N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * -5.0 + N[(N[(N[(N[(c * c), $MachinePrecision] * N[(-2.0 * N[(N[(c * N[(a * a), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] + (-a)), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] - c), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\left(c \cdot \left(c \cdot \left(a \cdot \left(a \cdot \left(a \cdot a\right)\right)\right)\right)\right) \cdot \frac{c \cdot c}{\left(b \cdot \left(b \cdot a\right)\right) \cdot \left(b \cdot \left(b \cdot \left(b \cdot b\right)\right)\right)}, -5, \frac{\left(c \cdot c\right) \cdot \mathsf{fma}\left(-2, \frac{c \cdot \left(a \cdot a\right)}{b \cdot b}, -a\right)}{b \cdot b} - c\right)}{b}
\end{array}
Initial program 17.4%
Taylor expanded in b around inf
Applied rewrites97.6%
Applied rewrites97.6%
Taylor expanded in c around 0
Applied rewrites97.6%
Applied rewrites97.6%
Final simplification97.6%
(FPCore (a b c) :precision binary64 (/ (- (* (* -2.0 (* a a)) (/ (* c (* c c)) (* (* b b) (* b b)))) (fma (* c c) (/ a (* b b)) c)) b))
double code(double a, double b, double c) {
return (((-2.0 * (a * a)) * ((c * (c * c)) / ((b * b) * (b * b)))) - fma((c * c), (a / (b * b)), c)) / b;
}
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * Float64(a * a)) * Float64(Float64(c * Float64(c * c)) / Float64(Float64(b * b) * Float64(b * b)))) - fma(Float64(c * c), Float64(a / Float64(b * b)), c)) / b) end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[(a * a), $MachinePrecision]), $MachinePrecision] * N[(N[(c * N[(c * c), $MachinePrecision]), $MachinePrecision] / N[(N[(b * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(c * c), $MachinePrecision] * N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision] + c), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-2 \cdot \left(a \cdot a\right)\right) \cdot \frac{c \cdot \left(c \cdot c\right)}{\left(b \cdot b\right) \cdot \left(b \cdot b\right)} - \mathsf{fma}\left(c \cdot c, \frac{a}{b \cdot b}, c\right)}{b}
\end{array}
Initial program 17.4%
Taylor expanded in b around inf
lower-/.f64N/A
Applied rewrites96.9%
(FPCore (a b c) :precision binary64 (/ (- (/ (- (* -2.0 (/ (* (* a a) (* c (* c c))) (* b b))) (* c (* a c))) (* b b)) c) b))
double code(double a, double b, double c) {
return ((((-2.0 * (((a * a) * (c * (c * c))) / (b * b))) - (c * (a * c))) / (b * b)) - 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 = (((((-2.0d0) * (((a * a) * (c * (c * c))) / (b * b))) - (c * (a * c))) / (b * b)) - c) / b
end function
public static double code(double a, double b, double c) {
return ((((-2.0 * (((a * a) * (c * (c * c))) / (b * b))) - (c * (a * c))) / (b * b)) - c) / b;
}
def code(a, b, c): return ((((-2.0 * (((a * a) * (c * (c * c))) / (b * b))) - (c * (a * c))) / (b * b)) - c) / b
function code(a, b, c) return Float64(Float64(Float64(Float64(Float64(-2.0 * Float64(Float64(Float64(a * a) * Float64(c * Float64(c * c))) / Float64(b * b))) - Float64(c * Float64(a * c))) / Float64(b * b)) - c) / b) end
function tmp = code(a, b, c) tmp = ((((-2.0 * (((a * a) * (c * (c * c))) / (b * b))) - (c * (a * c))) / (b * b)) - c) / b; end
code[a_, b_, c_] := N[(N[(N[(N[(N[(-2.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(c * N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] - c), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-2 \cdot \frac{\left(a \cdot a\right) \cdot \left(c \cdot \left(c \cdot c\right)\right)}{b \cdot b} - c \cdot \left(a \cdot c\right)}{b \cdot b} - c}{b}
\end{array}
Initial program 17.4%
Taylor expanded in b around inf
lower-/.f64N/A
Applied rewrites96.9%
Applied rewrites96.9%
Final simplification96.9%
(FPCore (a b c) :precision binary64 (/ 1.0 (fma a (fma (* a -2.0) (* (/ c (* b (* b b))) -0.5) (/ 1.0 b)) (/ b (- c)))))
double code(double a, double b, double c) {
return 1.0 / fma(a, fma((a * -2.0), ((c / (b * (b * b))) * -0.5), (1.0 / b)), (b / -c));
}
function code(a, b, c) return Float64(1.0 / fma(a, fma(Float64(a * -2.0), Float64(Float64(c / Float64(b * Float64(b * b))) * -0.5), Float64(1.0 / b)), Float64(b / Float64(-c)))) end
code[a_, b_, c_] := N[(1.0 / N[(a * N[(N[(a * -2.0), $MachinePrecision] * N[(N[(c / N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * -0.5), $MachinePrecision] + N[(1.0 / b), $MachinePrecision]), $MachinePrecision] + N[(b / (-c)), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a \cdot -2, \frac{c}{b \cdot \left(b \cdot b\right)} \cdot -0.5, \frac{1}{b}\right), \frac{b}{-c}\right)}
\end{array}
Initial program 17.4%
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6417.4
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-fma.f64N/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-*.f64N/A
metadata-eval17.4
Applied rewrites17.4%
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lower-*.f64N/A
lift-*.f64N/A
associate-/r*N/A
metadata-evalN/A
lower-/.f6417.4
lift-fma.f64N/A
lift-*.f64N/A
associate-*r*N/A
*-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
lower-fma.f6417.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6417.4
Applied rewrites17.4%
Applied rewrites17.4%
Taylor expanded in a around 0
+-commutativeN/A
lower-fma.f64N/A
associate-*r*N/A
lower-fma.f64N/A
lower-*.f64N/A
distribute-rgt-outN/A
metadata-evalN/A
lower-*.f64N/A
lower-/.f64N/A
cube-multN/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
lower-/.f64N/A
Applied rewrites96.7%
Final simplification96.7%
(FPCore (a b c) :precision binary64 (/ (fma (* c c) (/ a (* b b)) c) (- b)))
double code(double a, double b, double c) {
return fma((c * c), (a / (b * b)), c) / -b;
}
function code(a, b, c) return Float64(fma(Float64(c * c), Float64(a / Float64(b * b)), c) / Float64(-b)) end
code[a_, b_, c_] := N[(N[(N[(c * c), $MachinePrecision] * N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision] + c), $MachinePrecision] / (-b)), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(c \cdot c, \frac{a}{b \cdot b}, c\right)}{-b}
\end{array}
Initial program 17.4%
Taylor expanded in b around inf
distribute-lft-outN/A
associate-/l*N/A
mul-1-negN/A
lower-neg.f64N/A
lower-/.f64N/A
+-commutativeN/A
*-commutativeN/A
associate-/l*N/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f6495.6
Applied rewrites95.6%
Final simplification95.6%
(FPCore (a b c) :precision binary64 (/ 1.0 (- (/ a b) (/ b c))))
double code(double a, double b, double c) {
return 1.0 / ((a / b) - (b / c));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 1.0d0 / ((a / b) - (b / c))
end function
public static double code(double a, double b, double c) {
return 1.0 / ((a / b) - (b / c));
}
def code(a, b, c): return 1.0 / ((a / b) - (b / c))
function code(a, b, c) return Float64(1.0 / Float64(Float64(a / b) - Float64(b / c))) end
function tmp = code(a, b, c) tmp = 1.0 / ((a / b) - (b / c)); end
code[a_, b_, c_] := N[(1.0 / N[(N[(a / b), $MachinePrecision] - N[(b / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{a}{b} - \frac{b}{c}}
\end{array}
Initial program 17.4%
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6417.4
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-fma.f64N/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-*.f64N/A
metadata-eval17.4
Applied rewrites17.4%
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lower-*.f64N/A
lift-*.f64N/A
associate-/r*N/A
metadata-evalN/A
lower-/.f6417.4
lift-fma.f64N/A
lift-*.f64N/A
associate-*r*N/A
*-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
lower-fma.f6417.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6417.4
Applied rewrites17.4%
Applied rewrites17.4%
Taylor expanded in a around 0
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-/.f6495.4
Applied rewrites95.4%
(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 / Float64(-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 17.4%
Taylor expanded in b around inf
mul-1-negN/A
distribute-neg-frac2N/A
lower-/.f64N/A
lower-neg.f6490.9
Applied rewrites90.9%
(FPCore (a b c) :precision binary64 (/ 0.0 a))
double code(double a, double b, double c) {
return 0.0 / a;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 0.0d0 / a
end function
public static double code(double a, double b, double c) {
return 0.0 / a;
}
def code(a, b, c): return 0.0 / a
function code(a, b, c) return Float64(0.0 / a) end
function tmp = code(a, b, c) tmp = 0.0 / a; end
code[a_, b_, c_] := N[(0.0 / a), $MachinePrecision]
\begin{array}{l}
\\
\frac{0}{a}
\end{array}
Initial program 17.4%
lift-+.f64N/A
+-commutativeN/A
lift-neg.f64N/A
unsub-negN/A
lower--.f6417.4
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-fma.f64N/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lower-*.f64N/A
metadata-eval17.4
Applied rewrites17.4%
lift-/.f64N/A
lift--.f64N/A
div-subN/A
frac-subN/A
lower-/.f64N/A
Applied rewrites17.2%
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
lower-fma.f64N/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
lower-*.f6418.9
Applied rewrites18.9%
Taylor expanded in a around 0
associate-*r/N/A
distribute-rgt-outN/A
metadata-evalN/A
mul0-rgtN/A
metadata-evalN/A
lower-/.f643.3
Applied rewrites3.3%
herbie shell --seed 2024232
(FPCore (a b c)
:name "Quadratic roots, wide range"
:precision binary64
:pre (and (and (and (< 4.930380657631324e-32 a) (< a 2.028240960365167e+31)) (and (< 4.930380657631324e-32 b) (< b 2.028240960365167e+31))) (and (< 4.930380657631324e-32 c) (< c 2.028240960365167e+31)))
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))