
(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 6 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
(+
(* -0.5 (/ c b))
(*
a
(+
(* -0.375 (/ (pow c 2.0) (pow b 3.0)))
(*
a
(+
(* -0.5625 (/ (pow c 3.0) (pow b 5.0)))
(/ (* (* a -1.0546875) (pow c 4.0)) (pow b 7.0))))))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * ((-0.375 * (pow(c, 2.0) / pow(b, 3.0))) + (a * ((-0.5625 * (pow(c, 3.0) / pow(b, 5.0))) + (((a * -1.0546875) * pow(c, 4.0)) / pow(b, 7.0))))));
}
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)) + (a * (((-0.375d0) * ((c ** 2.0d0) / (b ** 3.0d0))) + (a * (((-0.5625d0) * ((c ** 3.0d0) / (b ** 5.0d0))) + (((a * (-1.0546875d0)) * (c ** 4.0d0)) / (b ** 7.0d0))))))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * ((-0.375 * (Math.pow(c, 2.0) / Math.pow(b, 3.0))) + (a * ((-0.5625 * (Math.pow(c, 3.0) / Math.pow(b, 5.0))) + (((a * -1.0546875) * Math.pow(c, 4.0)) / Math.pow(b, 7.0))))));
}
def code(a, b, c): return (-0.5 * (c / b)) + (a * ((-0.375 * (math.pow(c, 2.0) / math.pow(b, 3.0))) + (a * ((-0.5625 * (math.pow(c, 3.0) / math.pow(b, 5.0))) + (((a * -1.0546875) * math.pow(c, 4.0)) / math.pow(b, 7.0))))))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(a * Float64(Float64(-0.375 * Float64((c ^ 2.0) / (b ^ 3.0))) + Float64(a * Float64(Float64(-0.5625 * Float64((c ^ 3.0) / (b ^ 5.0))) + Float64(Float64(Float64(a * -1.0546875) * (c ^ 4.0)) / (b ^ 7.0))))))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (a * ((-0.375 * ((c ^ 2.0) / (b ^ 3.0))) + (a * ((-0.5625 * ((c ^ 3.0) / (b ^ 5.0))) + (((a * -1.0546875) * (c ^ 4.0)) / (b ^ 7.0)))))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(-0.375 * N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(-0.5625 * N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(a * -1.0546875), $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{\left(a \cdot -1.0546875\right) \cdot {c}^{4}}{{b}^{7}}\right)\right)
\end{array}
Initial program 15.3%
Simplified15.3%
Taylor expanded in a around 0 98.2%
Taylor expanded in c around 0 98.2%
associate-*r/98.2%
associate-*r*98.2%
Simplified98.2%
Final simplification98.2%
(FPCore (a b c)
:precision binary64
(+
(* -0.5 (/ c b))
(*
a
(*
(pow c 3.0)
(- (/ (* a -0.5625) (pow b 5.0)) (/ 0.375 (* c (pow b 3.0))))))))
double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * (pow(c, 3.0) * (((a * -0.5625) / pow(b, 5.0)) - (0.375 / (c * 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)) + (a * ((c ** 3.0d0) * (((a * (-0.5625d0)) / (b ** 5.0d0)) - (0.375d0 / (c * (b ** 3.0d0))))))
end function
public static double code(double a, double b, double c) {
return (-0.5 * (c / b)) + (a * (Math.pow(c, 3.0) * (((a * -0.5625) / Math.pow(b, 5.0)) - (0.375 / (c * Math.pow(b, 3.0))))));
}
def code(a, b, c): return (-0.5 * (c / b)) + (a * (math.pow(c, 3.0) * (((a * -0.5625) / math.pow(b, 5.0)) - (0.375 / (c * math.pow(b, 3.0))))))
function code(a, b, c) return Float64(Float64(-0.5 * Float64(c / b)) + Float64(a * Float64((c ^ 3.0) * Float64(Float64(Float64(a * -0.5625) / (b ^ 5.0)) - Float64(0.375 / Float64(c * (b ^ 3.0))))))) end
function tmp = code(a, b, c) tmp = (-0.5 * (c / b)) + (a * ((c ^ 3.0) * (((a * -0.5625) / (b ^ 5.0)) - (0.375 / (c * (b ^ 3.0)))))); end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[Power[c, 3.0], $MachinePrecision] * N[(N[(N[(a * -0.5625), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[(c * N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b} + a \cdot \left({c}^{3} \cdot \left(\frac{a \cdot -0.5625}{{b}^{5}} - \frac{0.375}{c \cdot {b}^{3}}\right)\right)
\end{array}
Initial program 15.3%
Simplified15.3%
Taylor expanded in a around 0 97.5%
Taylor expanded in c around inf 97.5%
associate-*r/97.5%
associate-*r/97.5%
metadata-eval97.5%
*-commutative97.5%
Simplified97.5%
Final simplification97.5%
(FPCore (a b c) :precision binary64 (/ 1.0 (+ (* -2.0 (/ b c)) (* a (+ (* 1.125 (/ (* c a) (pow b 3.0))) (* 1.5 (/ 1.0 b)))))))
double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (b / c)) + (a * ((1.125 * ((c * a) / pow(b, 3.0))) + (1.5 * (1.0 / b)))));
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 1.0d0 / (((-2.0d0) * (b / c)) + (a * ((1.125d0 * ((c * a) / (b ** 3.0d0))) + (1.5d0 * (1.0d0 / b)))))
end function
public static double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (b / c)) + (a * ((1.125 * ((c * a) / Math.pow(b, 3.0))) + (1.5 * (1.0 / b)))));
}
def code(a, b, c): return 1.0 / ((-2.0 * (b / c)) + (a * ((1.125 * ((c * a) / math.pow(b, 3.0))) + (1.5 * (1.0 / b)))))
function code(a, b, c) return Float64(1.0 / Float64(Float64(-2.0 * Float64(b / c)) + Float64(a * Float64(Float64(1.125 * Float64(Float64(c * a) / (b ^ 3.0))) + Float64(1.5 * Float64(1.0 / b)))))) end
function tmp = code(a, b, c) tmp = 1.0 / ((-2.0 * (b / c)) + (a * ((1.125 * ((c * a) / (b ^ 3.0))) + (1.5 * (1.0 / b))))); end
code[a_, b_, c_] := N[(1.0 / N[(N[(-2.0 * N[(b / c), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(1.125 * N[(N[(c * a), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.5 * N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{-2 \cdot \frac{b}{c} + a \cdot \left(1.125 \cdot \frac{c \cdot a}{{b}^{3}} + 1.5 \cdot \frac{1}{b}\right)}
\end{array}
Initial program 15.3%
expm1-log1p-u15.3%
expm1-undefine10.9%
Applied egg-rr10.9%
expm1-define15.3%
Simplified15.3%
expm1-log1p-u15.3%
clear-num15.3%
inv-pow15.3%
*-commutative15.3%
neg-mul-115.3%
fma-define15.3%
pow215.3%
*-commutative15.3%
*-commutative15.3%
Applied egg-rr15.3%
unpow-115.3%
unpow215.3%
fmm-def15.3%
associate-*r*15.3%
*-commutative15.3%
distribute-rgt-neg-in15.3%
metadata-eval15.3%
Simplified15.3%
Taylor expanded in b around inf 97.1%
fma-define97.1%
distribute-rgt-out97.1%
*-commutative97.1%
metadata-eval97.1%
associate-*r/97.1%
metadata-eval97.1%
Simplified97.1%
Taylor expanded in a around 0 97.3%
Final simplification97.3%
(FPCore (a b c) :precision binary64 (/ 1.0 (+ (* -2.0 (/ b c)) (* 1.5 (/ a b)))))
double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)));
}
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 / (((-2.0d0) * (b / c)) + (1.5d0 * (a / b)))
end function
public static double code(double a, double b, double c) {
return 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)));
}
def code(a, b, c): return 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)))
function code(a, b, c) return Float64(1.0 / Float64(Float64(-2.0 * Float64(b / c)) + Float64(1.5 * Float64(a / b)))) end
function tmp = code(a, b, c) tmp = 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b))); end
code[a_, b_, c_] := N[(1.0 / N[(N[(-2.0 * N[(b / c), $MachinePrecision]), $MachinePrecision] + N[(1.5 * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{-2 \cdot \frac{b}{c} + 1.5 \cdot \frac{a}{b}}
\end{array}
Initial program 15.3%
expm1-log1p-u15.3%
expm1-undefine10.9%
Applied egg-rr10.9%
expm1-define15.3%
Simplified15.3%
expm1-log1p-u15.3%
clear-num15.3%
inv-pow15.3%
*-commutative15.3%
neg-mul-115.3%
fma-define15.3%
pow215.3%
*-commutative15.3%
*-commutative15.3%
Applied egg-rr15.3%
unpow-115.3%
unpow215.3%
fmm-def15.3%
associate-*r*15.3%
*-commutative15.3%
distribute-rgt-neg-in15.3%
metadata-eval15.3%
Simplified15.3%
Taylor expanded in b around inf 97.1%
fma-define97.1%
distribute-rgt-out97.1%
*-commutative97.1%
metadata-eval97.1%
associate-*r/97.1%
metadata-eval97.1%
Simplified97.1%
Taylor expanded in a around 0 96.0%
(FPCore (a b c) :precision binary64 (* -0.5 (/ c b)))
double code(double a, double b, double c) {
return -0.5 * (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 = (-0.5d0) * (c / b)
end function
public static double code(double a, double b, double c) {
return -0.5 * (c / b);
}
def code(a, b, c): return -0.5 * (c / b)
function code(a, b, c) return Float64(-0.5 * Float64(c / b)) end
function tmp = code(a, b, c) tmp = -0.5 * (c / b); end
code[a_, b_, c_] := N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot \frac{c}{b}
\end{array}
Initial program 15.3%
Simplified15.3%
Taylor expanded in b around inf 92.1%
(FPCore (a b c) :precision binary64 0.0)
double code(double a, double b, double c) {
return 0.0;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
code = 0.0d0
end function
public static double code(double a, double b, double c) {
return 0.0;
}
def code(a, b, c): return 0.0
function code(a, b, c) return 0.0 end
function tmp = code(a, b, c) tmp = 0.0; end
code[a_, b_, c_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 15.3%
expm1-log1p-u15.3%
expm1-undefine10.9%
Applied egg-rr10.9%
expm1-define15.3%
Simplified15.3%
expm1-log1p-u15.3%
clear-num15.3%
inv-pow15.3%
*-commutative15.3%
neg-mul-115.3%
fma-define15.3%
pow215.3%
*-commutative15.3%
*-commutative15.3%
Applied egg-rr15.3%
unpow-115.3%
unpow215.3%
fmm-def15.3%
associate-*r*15.3%
*-commutative15.3%
distribute-rgt-neg-in15.3%
metadata-eval15.3%
Simplified15.3%
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%
Taylor expanded in a around 0 3.3%
herbie shell --seed 2024157
(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)))