
(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 (/ (/ (* c (* a 4.0)) (- (- b) (sqrt (fma b b (* (* c a) -4.0))))) (* a 2.0)))
double code(double a, double b, double c) {
return ((c * (a * 4.0)) / (-b - sqrt(fma(b, b, ((c * a) * -4.0))))) / (a * 2.0);
}
function code(a, b, c) return Float64(Float64(Float64(c * Float64(a * 4.0)) / Float64(Float64(-b) - sqrt(fma(b, b, Float64(Float64(c * a) * -4.0))))) / Float64(a * 2.0)) end
code[a_, b_, c_] := N[(N[(N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(b * b + N[(N[(c * a), $MachinePrecision] * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot 4\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, \left(c \cdot a\right) \cdot -4\right)}}}{a \cdot 2}
\end{array}
Initial program 16.8%
*-commutative16.8%
Simplified16.8%
neg-sub016.8%
flip--16.8%
metadata-eval16.8%
pow216.8%
add-sqr-sqrt17.4%
sqrt-prod16.8%
sqr-neg16.8%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod16.8%
sqr-neg16.8%
sqrt-prod17.4%
add-sqr-sqrt16.8%
Applied egg-rr16.8%
neg-sub016.8%
Simplified16.8%
flip-+16.8%
Applied egg-rr17.3%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
+-commutative99.4%
neg-mul-199.4%
distribute-rgt1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fmm-def99.4%
associate-*r*99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
*-commutative99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
associate-*r*99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
(FPCore (a b c) :precision binary64 (- (/ c (- b)) (* a (/ (pow c 2.0) (pow b 3.0)))))
double code(double a, double b, double c) {
return (c / -b) - (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 = (c / -b) - (a * ((c ** 2.0d0) / (b ** 3.0d0)))
end function
public static double code(double a, double b, double c) {
return (c / -b) - (a * (Math.pow(c, 2.0) / Math.pow(b, 3.0)));
}
def code(a, b, c): return (c / -b) - (a * (math.pow(c, 2.0) / math.pow(b, 3.0)))
function code(a, b, c) return Float64(Float64(c / Float64(-b)) - Float64(a * Float64((c ^ 2.0) / (b ^ 3.0)))) end
function tmp = code(a, b, c) tmp = (c / -b) - (a * ((c ^ 2.0) / (b ^ 3.0))); end
code[a_, b_, c_] := N[(N[(c / (-b)), $MachinePrecision] - N[(a * N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{c}{-b} - a \cdot \frac{{c}^{2}}{{b}^{3}}
\end{array}
Initial program 16.8%
*-commutative16.8%
Simplified16.8%
Taylor expanded in a around 0 95.8%
mul-1-neg95.8%
unsub-neg95.8%
mul-1-neg95.8%
distribute-neg-frac295.8%
associate-/l*95.8%
Simplified95.8%
(FPCore (a b c) :precision binary64 (/ (- (- c) (* a (pow (/ c (- b)) 2.0))) b))
double code(double a, double b, double c) {
return (-c - (a * pow((c / -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 - (a * ((c / -b) ** 2.0d0))) / b
end function
public static double code(double a, double b, double c) {
return (-c - (a * Math.pow((c / -b), 2.0))) / b;
}
def code(a, b, c): return (-c - (a * math.pow((c / -b), 2.0))) / b
function code(a, b, c) return Float64(Float64(Float64(-c) - Float64(a * (Float64(c / Float64(-b)) ^ 2.0))) / b) end
function tmp = code(a, b, c) tmp = (-c - (a * ((c / -b) ^ 2.0))) / b; end
code[a_, b_, c_] := N[(N[((-c) - N[(a * N[Power[N[(c / (-b)), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(-c\right) - a \cdot {\left(\frac{c}{-b}\right)}^{2}}{b}
\end{array}
Initial program 16.8%
*-commutative16.8%
Simplified16.8%
neg-sub016.8%
flip--16.8%
metadata-eval16.8%
pow216.8%
add-sqr-sqrt17.4%
sqrt-prod16.8%
sqr-neg16.8%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod16.8%
sqr-neg16.8%
sqrt-prod17.4%
add-sqr-sqrt16.8%
Applied egg-rr16.8%
neg-sub016.8%
Simplified16.8%
flip-+16.8%
Applied egg-rr17.3%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
+-commutative99.4%
neg-mul-199.4%
distribute-rgt1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fmm-def99.4%
associate-*r*99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
*-commutative99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
associate-*r*99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in b around inf 95.8%
Simplified95.8%
(FPCore (a b c) :precision binary64 (/ (/ (* c (* a 4.0)) (* 2.0 (- (* c (/ a b)) b))) (* a 2.0)))
double code(double a, double b, double c) {
return ((c * (a * 4.0)) / (2.0 * ((c * (a / b)) - b))) / (a * 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 * (a * 4.0d0)) / (2.0d0 * ((c * (a / b)) - b))) / (a * 2.0d0)
end function
public static double code(double a, double b, double c) {
return ((c * (a * 4.0)) / (2.0 * ((c * (a / b)) - b))) / (a * 2.0);
}
def code(a, b, c): return ((c * (a * 4.0)) / (2.0 * ((c * (a / b)) - b))) / (a * 2.0)
function code(a, b, c) return Float64(Float64(Float64(c * Float64(a * 4.0)) / Float64(2.0 * Float64(Float64(c * Float64(a / b)) - b))) / Float64(a * 2.0)) end
function tmp = code(a, b, c) tmp = ((c * (a * 4.0)) / (2.0 * ((c * (a / b)) - b))) / (a * 2.0); end
code[a_, b_, c_] := N[(N[(N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision] / N[(2.0 * N[(N[(c * N[(a / b), $MachinePrecision]), $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{c \cdot \left(a \cdot 4\right)}{2 \cdot \left(c \cdot \frac{a}{b} - b\right)}}{a \cdot 2}
\end{array}
Initial program 16.8%
*-commutative16.8%
Simplified16.8%
neg-sub016.8%
flip--16.8%
metadata-eval16.8%
pow216.8%
add-sqr-sqrt17.4%
sqrt-prod16.8%
sqr-neg16.8%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod16.8%
sqr-neg16.8%
sqrt-prod17.4%
add-sqr-sqrt16.8%
Applied egg-rr16.8%
neg-sub016.8%
Simplified16.8%
flip-+16.8%
Applied egg-rr17.3%
associate--r-99.4%
unpow299.4%
unpow299.4%
difference-of-squares99.4%
+-commutative99.4%
neg-mul-199.4%
distribute-rgt1-in99.4%
metadata-eval99.4%
mul0-lft99.4%
unpow299.4%
fmm-def99.4%
associate-*r*99.4%
*-commutative99.4%
distribute-rgt-neg-in99.4%
*-commutative99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in b around 0 99.4%
associate-*r*99.4%
*-commutative99.4%
*-commutative99.4%
Simplified99.4%
Taylor expanded in c around 0 95.5%
distribute-lft-out--95.5%
*-commutative95.5%
associate-/l*95.5%
Simplified95.5%
(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 16.8%
*-commutative16.8%
Simplified16.8%
Taylor expanded in a around 0 91.1%
associate-*r/91.1%
mul-1-neg91.1%
Simplified91.1%
Final simplification91.1%
(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 16.8%
*-commutative16.8%
Simplified16.8%
neg-sub016.8%
flip--16.8%
metadata-eval16.8%
pow216.8%
add-sqr-sqrt17.4%
sqrt-prod16.8%
sqr-neg16.8%
sqrt-unprod0.0%
add-sqr-sqrt1.6%
sub-neg1.6%
neg-sub01.6%
add-sqr-sqrt0.0%
sqrt-unprod16.8%
sqr-neg16.8%
sqrt-prod17.4%
add-sqr-sqrt16.8%
Applied egg-rr16.8%
neg-sub016.8%
Simplified16.8%
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 2024151
(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)))