
(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 8 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 (/ (* (* 4.0 c) a) (* (* a 2.0) (- (- b) (sqrt (fma b b (* a (* c -4.0))))))))
double code(double a, double b, double c) {
return ((4.0 * c) * a) / ((a * 2.0) * (-b - sqrt(fma(b, b, (a * (c * -4.0))))));
}
function code(a, b, c) return Float64(Float64(Float64(4.0 * c) * a) / Float64(Float64(a * 2.0) * Float64(Float64(-b) - sqrt(fma(b, b, Float64(a * Float64(c * -4.0))))))) end
code[a_, b_, c_] := N[(N[(N[(4.0 * c), $MachinePrecision] * a), $MachinePrecision] / N[(N[(a * 2.0), $MachinePrecision] * N[((-b) - N[Sqrt[N[(b * b + N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(4 \cdot c\right) \cdot a}{\left(a \cdot 2\right) \cdot \left(\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}\right)}
\end{array}
Initial program 34.7%
*-commutative34.7%
Simplified34.7%
add-cbrt-cube34.5%
pow1/335.1%
pow335.1%
pow235.1%
pow-pow35.2%
metadata-eval35.2%
Applied egg-rr35.2%
unpow1/334.1%
Simplified34.1%
flip-+34.1%
pow234.1%
add-sqr-sqrt34.6%
pow1/335.3%
pow-pow35.7%
metadata-eval35.7%
associate-*l*35.7%
pow1/335.6%
pow-pow35.7%
metadata-eval35.7%
associate-*l*35.7%
Applied egg-rr35.7%
*-un-lft-identity35.7%
associate-/l/35.7%
neg-mul-135.7%
unpow-prod-down35.7%
metadata-eval35.7%
*-un-lft-identity35.7%
cancel-sign-sub-inv35.7%
unpow235.7%
fma-define35.6%
metadata-eval35.6%
*-commutative35.6%
*-commutative35.6%
Applied egg-rr35.6%
*-lft-identity35.6%
metadata-eval35.6%
distribute-lft-neg-in35.6%
fma-neg35.7%
unpow235.7%
associate-+l-99.4%
+-inverses99.4%
+-commutative99.4%
associate-*r*99.4%
associate-*r*99.4%
Simplified99.4%
+-rgt-identity99.4%
Applied egg-rr99.4%
Final simplification99.4%
(FPCore (a b c) :precision binary64 (if (<= b 0.059) (/ 1.0 (* 2.0 (/ a (- (sqrt (fma b b (* a (* c -4.0)))) b)))) (/ 1.0 (/ (- (/ (* c a) b) b) c))))
double code(double a, double b, double c) {
double tmp;
if (b <= 0.059) {
tmp = 1.0 / (2.0 * (a / (sqrt(fma(b, b, (a * (c * -4.0)))) - b)));
} else {
tmp = 1.0 / ((((c * a) / b) - b) / c);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= 0.059) tmp = Float64(1.0 / Float64(2.0 * Float64(a / Float64(sqrt(fma(b, b, Float64(a * Float64(c * -4.0)))) - b)))); else tmp = Float64(1.0 / Float64(Float64(Float64(Float64(c * a) / b) - b) / c)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, 0.059], N[(1.0 / N[(2.0 * N[(a / N[(N[Sqrt[N[(b * b + N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision] - b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 0.059:\\
\;\;\;\;\frac{1}{2 \cdot \frac{a}{\sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)} - b}}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{\frac{\frac{c \cdot a}{b} - b}{c}}\\
\end{array}
\end{array}
if b < 0.058999999999999997Initial program 74.7%
*-commutative74.7%
Simplified74.7%
add-cbrt-cube74.1%
pow1/369.0%
pow369.0%
pow269.0%
pow-pow68.9%
metadata-eval68.9%
Applied egg-rr68.9%
unpow1/373.6%
Simplified73.6%
+-commutative73.6%
add-cube-cbrt71.1%
fma-define70.9%
Applied egg-rr72.6%
clear-num72.6%
inv-pow72.6%
Applied egg-rr74.8%
unpow-174.8%
associate-/l*74.8%
unsub-neg74.8%
associate-*r*74.8%
Simplified74.8%
if 0.058999999999999997 < b Initial program 25.4%
*-commutative25.4%
Simplified25.4%
add-cbrt-cube25.4%
pow1/327.3%
pow327.3%
pow227.3%
pow-pow27.4%
metadata-eval27.4%
Applied egg-rr27.4%
unpow1/325.0%
Simplified25.0%
+-commutative25.0%
add-cube-cbrt24.7%
fma-define24.9%
Applied egg-rr25.6%
clear-num25.6%
inv-pow25.6%
Applied egg-rr25.5%
unpow-125.5%
associate-/l*25.5%
unsub-neg25.5%
associate-*r*25.5%
Simplified25.5%
Taylor expanded in c around 0 93.7%
Final simplification90.2%
(FPCore (a b c) :precision binary64 (* (/ (* (* 4.0 c) a) (- (- b) (sqrt (fma b b (* a (* c -4.0)))))) (/ 0.5 a)))
double code(double a, double b, double c) {
return (((4.0 * c) * a) / (-b - sqrt(fma(b, b, (a * (c * -4.0)))))) * (0.5 / a);
}
function code(a, b, c) return Float64(Float64(Float64(Float64(4.0 * c) * a) / Float64(Float64(-b) - sqrt(fma(b, b, Float64(a * Float64(c * -4.0)))))) * Float64(0.5 / a)) end
code[a_, b_, c_] := N[(N[(N[(N[(4.0 * c), $MachinePrecision] * a), $MachinePrecision] / N[((-b) - N[Sqrt[N[(b * b + N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(0.5 / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(4 \cdot c\right) \cdot a}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}} \cdot \frac{0.5}{a}
\end{array}
Initial program 34.7%
*-commutative34.7%
Simplified34.7%
add-cbrt-cube34.5%
pow1/335.1%
pow335.1%
pow235.1%
pow-pow35.2%
metadata-eval35.2%
Applied egg-rr35.2%
unpow1/334.1%
Simplified34.1%
flip-+34.1%
pow234.1%
add-sqr-sqrt34.6%
pow1/335.3%
pow-pow35.7%
metadata-eval35.7%
associate-*l*35.7%
pow1/335.6%
pow-pow35.7%
metadata-eval35.7%
associate-*l*35.7%
Applied egg-rr35.7%
div-inv35.7%
Applied egg-rr35.6%
metadata-eval35.6%
distribute-lft-neg-in35.6%
fma-neg35.7%
unpow235.7%
associate-+l-99.2%
+-inverses99.2%
+-commutative99.2%
associate-*r*99.2%
associate-*r*99.2%
associate-/r*99.2%
metadata-eval99.2%
Simplified99.2%
+-rgt-identity99.4%
Applied egg-rr99.2%
Final simplification99.2%
(FPCore (a b c) :precision binary64 (if (<= b 0.059) (* (/ 0.5 a) (- (sqrt (fma b b (* a (* c -4.0)))) b)) (/ 1.0 (/ (- (/ (* c a) b) b) c))))
double code(double a, double b, double c) {
double tmp;
if (b <= 0.059) {
tmp = (0.5 / a) * (sqrt(fma(b, b, (a * (c * -4.0)))) - b);
} else {
tmp = 1.0 / ((((c * a) / b) - b) / c);
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= 0.059) tmp = Float64(Float64(0.5 / a) * Float64(sqrt(fma(b, b, Float64(a * Float64(c * -4.0)))) - b)); else tmp = Float64(1.0 / Float64(Float64(Float64(Float64(c * a) / b) - b) / c)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, 0.059], N[(N[(0.5 / a), $MachinePrecision] * N[(N[Sqrt[N[(b * b + N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision] - b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 0.059:\\
\;\;\;\;\frac{0.5}{a} \cdot \left(\sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)} - b\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{\frac{\frac{c \cdot a}{b} - b}{c}}\\
\end{array}
\end{array}
if b < 0.058999999999999997Initial program 74.7%
*-commutative74.7%
Simplified74.7%
add-cbrt-cube74.1%
pow1/369.0%
pow369.0%
pow269.0%
pow-pow68.9%
metadata-eval68.9%
Applied egg-rr68.9%
unpow1/373.6%
Simplified73.6%
+-commutative73.6%
add-cube-cbrt71.1%
fma-define70.9%
Applied egg-rr72.6%
div-inv72.6%
Applied egg-rr74.8%
unsub-neg74.8%
associate-*r*74.8%
associate-/r*74.8%
metadata-eval74.8%
Simplified74.8%
if 0.058999999999999997 < b Initial program 25.4%
*-commutative25.4%
Simplified25.4%
add-cbrt-cube25.4%
pow1/327.3%
pow327.3%
pow227.3%
pow-pow27.4%
metadata-eval27.4%
Applied egg-rr27.4%
unpow1/325.0%
Simplified25.0%
+-commutative25.0%
add-cube-cbrt24.7%
fma-define24.9%
Applied egg-rr25.6%
clear-num25.6%
inv-pow25.6%
Applied egg-rr25.5%
unpow-125.5%
associate-/l*25.5%
unsub-neg25.5%
associate-*r*25.5%
Simplified25.5%
Taylor expanded in c around 0 93.7%
Final simplification90.2%
(FPCore (a b c) :precision binary64 (if (<= b 0.059) (/ (- (sqrt (- (* b b) (* c (* 4.0 a)))) b) (* a 2.0)) (/ 1.0 (/ (- (/ (* c a) b) b) c))))
double code(double a, double b, double c) {
double tmp;
if (b <= 0.059) {
tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0);
} else {
tmp = 1.0 / ((((c * a) / b) - b) / c);
}
return tmp;
}
real(8) function code(a, b, c)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8) :: tmp
if (b <= 0.059d0) then
tmp = (sqrt(((b * b) - (c * (4.0d0 * a)))) - b) / (a * 2.0d0)
else
tmp = 1.0d0 / ((((c * a) / b) - b) / c)
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 0.059) {
tmp = (Math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0);
} else {
tmp = 1.0 / ((((c * a) / b) - b) / c);
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 0.059: tmp = (math.sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0) else: tmp = 1.0 / ((((c * a) / b) - b) / c) return tmp
function code(a, b, c) tmp = 0.0 if (b <= 0.059) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(4.0 * a)))) - b) / Float64(a * 2.0)); else tmp = Float64(1.0 / Float64(Float64(Float64(Float64(c * a) / b) - b) / c)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 0.059) tmp = (sqrt(((b * b) - (c * (4.0 * a)))) - b) / (a * 2.0); else tmp = 1.0 / ((((c * a) / b) - b) / c); end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 0.059], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(4.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision] - b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 0.059:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{\frac{\frac{c \cdot a}{b} - b}{c}}\\
\end{array}
\end{array}
if b < 0.058999999999999997Initial program 74.7%
if 0.058999999999999997 < b Initial program 25.4%
*-commutative25.4%
Simplified25.4%
add-cbrt-cube25.4%
pow1/327.3%
pow327.3%
pow227.3%
pow-pow27.4%
metadata-eval27.4%
Applied egg-rr27.4%
unpow1/325.0%
Simplified25.0%
+-commutative25.0%
add-cube-cbrt24.7%
fma-define24.9%
Applied egg-rr25.6%
clear-num25.6%
inv-pow25.6%
Applied egg-rr25.5%
unpow-125.5%
associate-/l*25.5%
unsub-neg25.5%
associate-*r*25.5%
Simplified25.5%
Taylor expanded in c around 0 93.7%
Final simplification90.2%
(FPCore (a b c) :precision binary64 (/ 1.0 (/ (- (/ (* c a) b) b) c)))
double code(double a, double b, double c) {
return 1.0 / ((((c * 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 / ((((c * a) / b) - b) / c)
end function
public static double code(double a, double b, double c) {
return 1.0 / ((((c * a) / b) - b) / c);
}
def code(a, b, c): return 1.0 / ((((c * a) / b) - b) / c)
function code(a, b, c) return Float64(1.0 / Float64(Float64(Float64(Float64(c * a) / b) - b) / c)) end
function tmp = code(a, b, c) tmp = 1.0 / ((((c * a) / b) - b) / c); end
code[a_, b_, c_] := N[(1.0 / N[(N[(N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision] - b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{\frac{c \cdot a}{b} - b}{c}}
\end{array}
Initial program 34.7%
*-commutative34.7%
Simplified34.7%
add-cbrt-cube34.5%
pow1/335.1%
pow335.1%
pow235.1%
pow-pow35.2%
metadata-eval35.2%
Applied egg-rr35.2%
unpow1/334.1%
Simplified34.1%
+-commutative34.1%
add-cube-cbrt33.4%
fma-define33.5%
Applied egg-rr34.4%
clear-num34.4%
inv-pow34.4%
Applied egg-rr34.7%
unpow-134.7%
associate-/l*34.7%
unsub-neg34.7%
associate-*r*34.7%
Simplified34.7%
Taylor expanded in c around 0 88.5%
Final simplification88.5%
(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 34.7%
*-commutative34.7%
Simplified34.7%
add-cbrt-cube34.5%
pow1/335.1%
pow335.1%
pow235.1%
pow-pow35.2%
metadata-eval35.2%
Applied egg-rr35.2%
unpow1/334.1%
Simplified34.1%
+-commutative34.1%
add-cube-cbrt33.4%
fma-define33.5%
Applied egg-rr34.4%
clear-num34.4%
inv-pow34.4%
Applied egg-rr34.7%
unpow-134.7%
associate-/l*34.7%
unsub-neg34.7%
associate-*r*34.7%
Simplified34.7%
Taylor expanded in a around 0 88.5%
Final simplification88.5%
(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(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 34.7%
*-commutative34.7%
Simplified34.7%
Taylor expanded in b around inf 78.7%
associate-*r/78.7%
mul-1-neg78.7%
Simplified78.7%
herbie shell --seed 2024135
(FPCore (a b c)
:name "Quadratic roots, medium range"
:precision binary64
:pre (and (and (and (< 1.1102230246251565e-16 a) (< a 9007199254740992.0)) (and (< 1.1102230246251565e-16 b) (< b 9007199254740992.0))) (and (< 1.1102230246251565e-16 c) (< c 9007199254740992.0)))
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))