
(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 6 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
(let* ((t_0 (sqrt (* a c))))
(/
(* 2.0 (/ (* a c) a))
(- (- b) (sqrt (* (fma t_0 2.0 b) (fma -2.0 t_0 b)))))))
double code(double a, double b, double c) {
double t_0 = sqrt((a * c));
return (2.0 * ((a * c) / a)) / (-b - sqrt((fma(t_0, 2.0, b) * fma(-2.0, t_0, b))));
}
function code(a, b, c) t_0 = sqrt(Float64(a * c)) return Float64(Float64(2.0 * Float64(Float64(a * c) / a)) / Float64(Float64(-b) - sqrt(Float64(fma(t_0, 2.0, b) * fma(-2.0, t_0, b))))) end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(a * c), $MachinePrecision]], $MachinePrecision]}, N[(N[(2.0 * N[(N[(a * c), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(N[(t$95$0 * 2.0 + b), $MachinePrecision] * N[(-2.0 * t$95$0 + b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{a \cdot c}\\
\frac{2 \cdot \frac{a \cdot c}{a}}{\left(-b\right) - \sqrt{\mathsf{fma}\left(t_0, 2, b\right) \cdot \mathsf{fma}\left(-2, t_0, b\right)}}
\end{array}
\end{array}
Initial program 19.4%
*-commutative19.4%
Simplified19.4%
add-sqr-sqrt19.4%
difference-of-squares19.4%
associate-*l*19.4%
sqrt-prod19.4%
metadata-eval19.4%
associate-*l*19.4%
sqrt-prod19.4%
metadata-eval19.4%
Applied egg-rr19.4%
*-commutative19.4%
cancel-sign-sub-inv19.4%
metadata-eval19.4%
Simplified19.4%
flip-+19.2%
pow219.2%
add-sqr-sqrt19.6%
+-commutative19.6%
*-commutative19.6%
fma-def19.6%
+-commutative19.6%
fma-def19.6%
Applied egg-rr19.6%
unpow219.6%
sqr-neg19.6%
unpow219.6%
fma-udef19.6%
*-commutative19.6%
fma-def19.6%
fma-udef19.6%
*-commutative19.6%
fma-def19.6%
Simplified19.6%
Taylor expanded in b around 0 99.4%
associate-*r*99.4%
Simplified99.4%
expm1-log1p-u82.7%
expm1-udef22.9%
associate-/l/22.9%
associate-*l*22.9%
Applied egg-rr22.9%
expm1-def82.6%
expm1-log1p99.3%
associate-/r*99.7%
*-commutative99.7%
times-frac99.7%
metadata-eval99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (a b c) :precision binary64 (- (- (/ (* -2.0 (* (pow c 3.0) (pow a 2.0))) (pow b 5.0)) (/ c b)) (/ a (/ (pow b 3.0) (pow c 2.0)))))
double code(double a, double b, double c) {
return (((-2.0 * (pow(c, 3.0) * pow(a, 2.0))) / pow(b, 5.0)) - (c / b)) - (a / (pow(b, 3.0) / pow(c, 2.0)));
}
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) * ((c ** 3.0d0) * (a ** 2.0d0))) / (b ** 5.0d0)) - (c / b)) - (a / ((b ** 3.0d0) / (c ** 2.0d0)))
end function
public static double code(double a, double b, double c) {
return (((-2.0 * (Math.pow(c, 3.0) * Math.pow(a, 2.0))) / Math.pow(b, 5.0)) - (c / b)) - (a / (Math.pow(b, 3.0) / Math.pow(c, 2.0)));
}
def code(a, b, c): return (((-2.0 * (math.pow(c, 3.0) * math.pow(a, 2.0))) / math.pow(b, 5.0)) - (c / b)) - (a / (math.pow(b, 3.0) / math.pow(c, 2.0)))
function code(a, b, c) return Float64(Float64(Float64(Float64(-2.0 * Float64((c ^ 3.0) * (a ^ 2.0))) / (b ^ 5.0)) - Float64(c / b)) - Float64(a / Float64((b ^ 3.0) / (c ^ 2.0)))) end
function tmp = code(a, b, c) tmp = (((-2.0 * ((c ^ 3.0) * (a ^ 2.0))) / (b ^ 5.0)) - (c / b)) - (a / ((b ^ 3.0) / (c ^ 2.0))); end
code[a_, b_, c_] := N[(N[(N[(N[(-2.0 * N[(N[Power[c, 3.0], $MachinePrecision] * N[Power[a, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(c / b), $MachinePrecision]), $MachinePrecision] - N[(a / N[(N[Power[b, 3.0], $MachinePrecision] / N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2 \cdot \left({c}^{3} \cdot {a}^{2}\right)}{{b}^{5}} - \frac{c}{b}\right) - \frac{a}{\frac{{b}^{3}}{{c}^{2}}}
\end{array}
Initial program 19.4%
*-commutative19.4%
Simplified19.4%
Taylor expanded in b around inf 96.7%
associate-+r+96.7%
mul-1-neg96.7%
unsub-neg96.7%
mul-1-neg96.7%
unsub-neg96.7%
associate-*r/96.7%
*-commutative96.7%
associate-/l*96.7%
Simplified96.7%
Final simplification96.7%
(FPCore (a b c) :precision binary64 (- (/ (- c) b) (/ a (/ (pow b 3.0) (pow c 2.0)))))
double code(double a, double b, double c) {
return (-c / b) - (a / (pow(b, 3.0) / pow(c, 2.0)));
}
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) - (a / ((b ** 3.0d0) / (c ** 2.0d0)))
end function
public static double code(double a, double b, double c) {
return (-c / b) - (a / (Math.pow(b, 3.0) / Math.pow(c, 2.0)));
}
def code(a, b, c): return (-c / b) - (a / (math.pow(b, 3.0) / math.pow(c, 2.0)))
function code(a, b, c) return Float64(Float64(Float64(-c) / b) - Float64(a / Float64((b ^ 3.0) / (c ^ 2.0)))) end
function tmp = code(a, b, c) tmp = (-c / b) - (a / ((b ^ 3.0) / (c ^ 2.0))); end
code[a_, b_, c_] := N[(N[((-c) / b), $MachinePrecision] - N[(a / N[(N[Power[b, 3.0], $MachinePrecision] / N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-c}{b} - \frac{a}{\frac{{b}^{3}}{{c}^{2}}}
\end{array}
Initial program 19.4%
*-commutative19.4%
Simplified19.4%
Taylor expanded in b around inf 95.1%
mul-1-neg95.1%
unsub-neg95.1%
mul-1-neg95.1%
distribute-neg-frac95.1%
associate-/l*95.1%
Simplified95.1%
Final simplification95.1%
(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 19.4%
*-commutative19.4%
Simplified19.4%
Taylor expanded in b around inf 94.7%
distribute-lft-out94.7%
associate-/l*94.6%
associate-/l*94.6%
Simplified94.6%
clear-num94.7%
inv-pow94.7%
+-commutative94.7%
associate-/r/94.7%
fma-def94.7%
associate-/r/94.5%
Applied egg-rr94.5%
unpow-194.5%
times-frac94.5%
*-commutative94.5%
Simplified94.5%
Taylor expanded in a around 0 94.9%
+-commutative94.9%
neg-mul-194.9%
unsub-neg94.9%
Simplified94.9%
Final simplification94.9%
(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(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 19.4%
*-commutative19.4%
Simplified19.4%
Taylor expanded in b around inf 89.7%
mul-1-neg89.7%
distribute-neg-frac89.7%
Simplified89.7%
Final simplification89.7%
(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 19.4%
*-commutative19.4%
Simplified19.4%
add-sqr-sqrt19.4%
difference-of-squares19.4%
associate-*l*19.4%
sqrt-prod19.4%
metadata-eval19.4%
associate-*l*19.4%
sqrt-prod19.4%
metadata-eval19.4%
Applied egg-rr19.4%
*-commutative19.4%
cancel-sign-sub-inv19.4%
metadata-eval19.4%
Simplified19.4%
Taylor expanded in b around inf 3.3%
associate-*r/3.3%
distribute-rgt-out3.3%
metadata-eval3.3%
mul0-rgt3.3%
metadata-eval3.3%
Simplified3.3%
Final simplification3.3%
herbie shell --seed 2023306
(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)))