
(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 8 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 (/ (/ (* a (* c 3.0)) (* a 3.0)) (- (- b) (sqrt (fma -3.0 (* a c) (pow b 2.0))))))
double code(double a, double b, double c) {
return ((a * (c * 3.0)) / (a * 3.0)) / (-b - sqrt(fma(-3.0, (a * c), pow(b, 2.0))));
}
function code(a, b, c) return Float64(Float64(Float64(a * Float64(c * 3.0)) / Float64(a * 3.0)) / Float64(Float64(-b) - sqrt(fma(-3.0, Float64(a * c), (b ^ 2.0))))) end
code[a_, b_, c_] := N[(N[(N[(a * N[(c * 3.0), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(-3.0 * N[(a * c), $MachinePrecision] + N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{a \cdot \left(c \cdot 3\right)}{a \cdot 3}}{\left(-b\right) - \sqrt{\mathsf{fma}\left(-3, a \cdot c, {b}^{2}\right)}}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
expm1-log1p-u19.5%
expm1-undefine12.0%
*-commutative12.0%
*-commutative12.0%
associate-*l*12.0%
*-commutative12.0%
Applied egg-rr12.0%
expm1-define19.5%
associate-*r*19.5%
Simplified19.5%
flip-+19.6%
pow219.6%
add-sqr-sqrt20.0%
pow220.0%
expm1-log1p-u20.0%
*-commutative20.0%
pow220.0%
expm1-log1p-u20.1%
*-commutative20.1%
Applied egg-rr20.1%
associate--r-99.3%
Simplified99.3%
div-inv99.2%
+-commutative99.2%
*-commutative99.2%
fma-define99.2%
*-commutative99.2%
neg-mul-199.2%
unpow-prod-down99.2%
metadata-eval99.2%
*-un-lft-identity99.2%
*-commutative99.2%
Applied egg-rr99.2%
*-commutative99.2%
times-frac99.2%
associate-*r/99.2%
*-lft-identity99.2%
associate-/r*99.4%
fma-undefine99.4%
+-inverses99.4%
+-rgt-identity99.4%
associate-*r*99.4%
*-commutative99.4%
sub-neg99.4%
+-commutative99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (/ (+ (* c -0.5) (* -0.375 (/ (* a (pow c 2.0)) (pow b 2.0)))) b))
double code(double a, double b, double c) {
return ((c * -0.5) + (-0.375 * ((a * pow(c, 2.0)) / pow(b, 2.0)))) / 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 * (-0.5d0)) + ((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 2.0d0)))) / b
end function
public static double code(double a, double b, double c) {
return ((c * -0.5) + (-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 2.0)))) / b;
}
def code(a, b, c): return ((c * -0.5) + (-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 2.0)))) / b
function code(a, b, c) return Float64(Float64(Float64(c * -0.5) + Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 2.0)))) / b) end
function tmp = code(a, b, c) tmp = ((c * -0.5) + (-0.375 * ((a * (c ^ 2.0)) / (b ^ 2.0)))) / b; end
code[a_, b_, c_] := N[(N[(N[(c * -0.5), $MachinePrecision] + N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot -0.5 + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
Taylor expanded in b around inf 94.2%
Final simplification94.2%
(FPCore (a b c) :precision binary64 (+ (* -0.5 (/ c b)) (* -0.375 (/ (* a (pow c 2.0)) (pow b 3.0)))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * ((a * pow(c, 2.0)) / pow(b, 3.0)));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = ((-0.5d0) * (c / b)) + ((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (-0.5 * (c / b)) + (-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (-0.375 * ((a * (c ^ 2.0)) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
Taylor expanded in a around 0 94.2%
(FPCore (a b c) :precision binary64 (/ 1.0 (* b (- (* 1.5 (/ a (pow b 2.0))) (/ 2.0 c)))))
double code(double a, double b, double c) {
return 1.0 / (b * ((1.5 * (a / pow(b, 2.0))) - (2.0 / 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 / (b * ((1.5d0 * (a / (b ** 2.0d0))) - (2.0d0 / c)))
end function
public static double code(double a, double b, double c) {
return 1.0 / (b * ((1.5 * (a / Math.pow(b, 2.0))) - (2.0 / c)));
}
def code(a, b, c): return 1.0 / (b * ((1.5 * (a / math.pow(b, 2.0))) - (2.0 / c)))
function code(a, b, c) return Float64(1.0 / Float64(b * Float64(Float64(1.5 * Float64(a / (b ^ 2.0))) - Float64(2.0 / c)))) end
function tmp = code(a, b, c) tmp = 1.0 / (b * ((1.5 * (a / (b ^ 2.0))) - (2.0 / c))); end
code[a_, b_, c_] := N[(1.0 / N[(b * N[(N[(1.5 * N[(a / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(2.0 / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{b \cdot \left(1.5 \cdot \frac{a}{{b}^{2}} - \frac{2}{c}\right)}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
expm1-log1p-u19.5%
expm1-undefine12.0%
*-commutative12.0%
*-commutative12.0%
associate-*l*12.0%
*-commutative12.0%
Applied egg-rr12.0%
expm1-define19.5%
associate-*r*19.5%
Simplified19.5%
clear-num19.5%
inv-pow19.5%
*-commutative19.5%
neg-mul-119.5%
fma-define19.5%
pow219.5%
expm1-log1p-u19.5%
*-commutative19.5%
Applied egg-rr19.5%
unpow-119.5%
associate-/l*19.5%
Simplified19.5%
Taylor expanded in b around inf 94.0%
associate-*r/94.0%
metadata-eval94.0%
Simplified94.0%
(FPCore (a b c) :precision binary64 (* c (- (* -0.375 (* a (/ c (pow b 3.0)))) (/ 0.5 b))))
double code(double a, double b, double c) {
return c * ((-0.375 * (a * (c / pow(b, 3.0)))) - (0.5 / 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 * (((-0.375d0) * (a * (c / (b ** 3.0d0)))) - (0.5d0 / b))
end function
public static double code(double a, double b, double c) {
return c * ((-0.375 * (a * (c / Math.pow(b, 3.0)))) - (0.5 / b));
}
def code(a, b, c): return c * ((-0.375 * (a * (c / math.pow(b, 3.0)))) - (0.5 / b))
function code(a, b, c) return Float64(c * Float64(Float64(-0.375 * Float64(a * Float64(c / (b ^ 3.0)))) - Float64(0.5 / b))) end
function tmp = code(a, b, c) tmp = c * ((-0.375 * (a * (c / (b ^ 3.0)))) - (0.5 / b)); end
code[a_, b_, c_] := N[(c * N[(N[(-0.375 * N[(a * N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \left(-0.375 \cdot \left(a \cdot \frac{c}{{b}^{3}}\right) - \frac{0.5}{b}\right)
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
Taylor expanded in c around 0 93.9%
sub-neg93.9%
associate-/l*93.9%
un-div-inv93.9%
Applied egg-rr93.9%
Taylor expanded in c around 0 93.9%
associate-/l*93.9%
associate-*r/93.9%
metadata-eval93.9%
Simplified93.9%
(FPCore (a b c) :precision binary64 (/ (* c -0.5) b))
double code(double a, double b, double c) {
return (c * -0.5) / 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 * (-0.5d0)) / b
end function
public static double code(double a, double b, double c) {
return (c * -0.5) / b;
}
def code(a, b, c): return (c * -0.5) / b
function code(a, b, c) return Float64(Float64(c * -0.5) / b) end
function tmp = code(a, b, c) tmp = (c * -0.5) / b; end
code[a_, b_, c_] := N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{c \cdot -0.5}{b}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
Taylor expanded in b around inf 88.8%
associate-*r/88.8%
*-commutative88.8%
Simplified88.8%
(FPCore (a b c) :precision binary64 (* c (/ -0.5 b)))
double code(double a, double b, double c) {
return c * (-0.5 / 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 * ((-0.5d0) / b)
end function
public static double code(double a, double b, double c) {
return c * (-0.5 / b);
}
def code(a, b, c): return c * (-0.5 / b)
function code(a, b, c) return Float64(c * Float64(-0.5 / b)) end
function tmp = code(a, b, c) tmp = c * (-0.5 / b); end
code[a_, b_, c_] := N[(c * N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \frac{-0.5}{b}
\end{array}
Initial program 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
Taylor expanded in c around 0 93.9%
Taylor expanded in a around 0 88.5%
(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 19.5%
sqr-neg19.5%
sqr-neg19.5%
associate-*l*19.5%
Simplified19.5%
expm1-log1p-u19.5%
expm1-undefine12.0%
*-commutative12.0%
*-commutative12.0%
associate-*l*12.0%
*-commutative12.0%
Applied egg-rr12.0%
expm1-define19.5%
associate-*r*19.5%
Simplified19.5%
clear-num19.5%
inv-pow19.5%
*-commutative19.5%
neg-mul-119.5%
fma-define19.5%
pow219.5%
expm1-log1p-u19.5%
*-commutative19.5%
Applied egg-rr19.5%
unpow-119.5%
associate-/l*19.5%
Simplified19.5%
Taylor expanded in a around 0 3.3%
associate-*r/3.3%
distribute-rgt1-in3.3%
metadata-eval3.3%
mul0-lft3.3%
metadata-eval3.3%
Simplified3.3%
herbie shell --seed 2024108
(FPCore (a b c)
:name "Cubic critical, 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) (* (* 3.0 a) c)))) (* 3.0 a)))