
(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 7 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
(if (<= b -3.2e-15)
(- (/ b a))
(if (<= b 0.102)
(/ (- (sqrt (fma a (* c -4.0) (* b b))) b) (* a 2.0))
(/ c (- b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -3.2e-15) {
tmp = -(b / a);
} else if (b <= 0.102) {
tmp = (sqrt(fma(a, (c * -4.0), (b * b))) - b) / (a * 2.0);
} else {
tmp = c / -b;
}
return tmp;
}
function code(a, b, c) tmp = 0.0 if (b <= -3.2e-15) tmp = Float64(-Float64(b / a)); elseif (b <= 0.102) tmp = Float64(Float64(sqrt(fma(a, Float64(c * -4.0), Float64(b * b))) - b) / Float64(a * 2.0)); else tmp = Float64(c / Float64(-b)); end return tmp end
code[a_, b_, c_] := If[LessEqual[b, -3.2e-15], (-N[(b / a), $MachinePrecision]), If[LessEqual[b, 0.102], N[(N[(N[Sqrt[N[(a * N[(c * -4.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(c / (-b)), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -3.2 \cdot 10^{-15}:\\
\;\;\;\;-\frac{b}{a}\\
\mathbf{elif}\;b \leq 0.102:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -4, b \cdot b\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{-b}\\
\end{array}
\end{array}
if b < -3.1999999999999999e-15Initial program 68.8%
*-commutative68.8%
Simplified68.8%
Taylor expanded in b around -inf 93.9%
mul-1-neg93.9%
Simplified93.9%
if -3.1999999999999999e-15 < b < 0.101999999999999993Initial program 80.8%
*-commutative80.8%
Simplified80.8%
if 0.101999999999999993 < b Initial program 14.4%
*-commutative14.4%
Simplified14.4%
Taylor expanded in b around inf 91.1%
associate-*r/91.1%
mul-1-neg91.1%
Simplified91.1%
Final simplification88.1%
(FPCore (a b c)
:precision binary64
(if (<= b -3.2e-15)
(- (/ b a))
(if (<= b 0.27)
(/ (- (sqrt (- (* b b) (* c (* a 4.0)))) b) (* a 2.0))
(/ c (- b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -3.2e-15) {
tmp = -(b / a);
} else if (b <= 0.27) {
tmp = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
} else {
tmp = c / -b;
}
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 <= (-3.2d-15)) then
tmp = -(b / a)
else if (b <= 0.27d0) then
tmp = (sqrt(((b * b) - (c * (a * 4.0d0)))) - b) / (a * 2.0d0)
else
tmp = c / -b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= -3.2e-15) {
tmp = -(b / a);
} else if (b <= 0.27) {
tmp = (Math.sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0);
} else {
tmp = c / -b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -3.2e-15: tmp = -(b / a) elif b <= 0.27: tmp = (math.sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0) else: tmp = c / -b return tmp
function code(a, b, c) tmp = 0.0 if (b <= -3.2e-15) tmp = Float64(-Float64(b / a)); elseif (b <= 0.27) tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 4.0)))) - b) / Float64(a * 2.0)); else tmp = Float64(c / Float64(-b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -3.2e-15) tmp = -(b / a); elseif (b <= 0.27) tmp = (sqrt(((b * b) - (c * (a * 4.0)))) - b) / (a * 2.0); else tmp = c / -b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -3.2e-15], (-N[(b / a), $MachinePrecision]), If[LessEqual[b, 0.27], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(c / (-b)), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -3.2 \cdot 10^{-15}:\\
\;\;\;\;-\frac{b}{a}\\
\mathbf{elif}\;b \leq 0.27:\\
\;\;\;\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{-b}\\
\end{array}
\end{array}
if b < -3.1999999999999999e-15Initial program 68.8%
*-commutative68.8%
Simplified68.8%
Taylor expanded in b around -inf 93.9%
mul-1-neg93.9%
Simplified93.9%
if -3.1999999999999999e-15 < b < 0.27000000000000002Initial program 80.8%
if 0.27000000000000002 < b Initial program 14.4%
*-commutative14.4%
Simplified14.4%
Taylor expanded in b around inf 91.1%
associate-*r/91.1%
mul-1-neg91.1%
Simplified91.1%
Final simplification88.1%
(FPCore (a b c) :precision binary64 (if (<= b -9.5e-104) (- (/ b a)) (if (<= b 0.102) (/ (- (sqrt (* a (* c -4.0))) b) (* a 2.0)) (/ c (- b)))))
double code(double a, double b, double c) {
double tmp;
if (b <= -9.5e-104) {
tmp = -(b / a);
} else if (b <= 0.102) {
tmp = (sqrt((a * (c * -4.0))) - b) / (a * 2.0);
} else {
tmp = c / -b;
}
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 <= (-9.5d-104)) then
tmp = -(b / a)
else if (b <= 0.102d0) then
tmp = (sqrt((a * (c * (-4.0d0)))) - b) / (a * 2.0d0)
else
tmp = c / -b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= -9.5e-104) {
tmp = -(b / a);
} else if (b <= 0.102) {
tmp = (Math.sqrt((a * (c * -4.0))) - b) / (a * 2.0);
} else {
tmp = c / -b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= -9.5e-104: tmp = -(b / a) elif b <= 0.102: tmp = (math.sqrt((a * (c * -4.0))) - b) / (a * 2.0) else: tmp = c / -b return tmp
function code(a, b, c) tmp = 0.0 if (b <= -9.5e-104) tmp = Float64(-Float64(b / a)); elseif (b <= 0.102) tmp = Float64(Float64(sqrt(Float64(a * Float64(c * -4.0))) - b) / Float64(a * 2.0)); else tmp = Float64(c / Float64(-b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= -9.5e-104) tmp = -(b / a); elseif (b <= 0.102) tmp = (sqrt((a * (c * -4.0))) - b) / (a * 2.0); else tmp = c / -b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, -9.5e-104], (-N[(b / a), $MachinePrecision]), If[LessEqual[b, 0.102], N[(N[(N[Sqrt[N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], N[(c / (-b)), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq -9.5 \cdot 10^{-104}:\\
\;\;\;\;-\frac{b}{a}\\
\mathbf{elif}\;b \leq 0.102:\\
\;\;\;\;\frac{\sqrt{a \cdot \left(c \cdot -4\right)} - b}{a \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{-b}\\
\end{array}
\end{array}
if b < -9.5000000000000002e-104Initial program 73.5%
*-commutative73.5%
Simplified73.5%
Taylor expanded in b around -inf 88.6%
mul-1-neg88.6%
Simplified88.6%
if -9.5000000000000002e-104 < b < 0.101999999999999993Initial program 78.0%
*-commutative78.0%
Simplified78.0%
Taylor expanded in b around 0 73.4%
*-commutative73.4%
associate-*r*73.4%
Simplified73.4%
if 0.101999999999999993 < b Initial program 14.4%
*-commutative14.4%
Simplified14.4%
Taylor expanded in b around inf 91.1%
associate-*r/91.1%
mul-1-neg91.1%
Simplified91.1%
Final simplification85.0%
(FPCore (a b c) :precision binary64 (if (<= b 6.8e-306) (- (/ b a)) (/ c (- b))))
double code(double a, double b, double c) {
double tmp;
if (b <= 6.8e-306) {
tmp = -(b / a);
} else {
tmp = c / -b;
}
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 <= 6.8d-306) then
tmp = -(b / a)
else
tmp = c / -b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 6.8e-306) {
tmp = -(b / a);
} else {
tmp = c / -b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 6.8e-306: tmp = -(b / a) else: tmp = c / -b return tmp
function code(a, b, c) tmp = 0.0 if (b <= 6.8e-306) tmp = Float64(-Float64(b / a)); else tmp = Float64(c / Float64(-b)); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 6.8e-306) tmp = -(b / a); else tmp = c / -b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 6.8e-306], (-N[(b / a), $MachinePrecision]), N[(c / (-b)), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.8 \cdot 10^{-306}:\\
\;\;\;\;-\frac{b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{-b}\\
\end{array}
\end{array}
if b < 6.7999999999999996e-306Initial program 76.7%
*-commutative76.7%
Simplified76.7%
Taylor expanded in b around -inf 66.5%
mul-1-neg66.5%
Simplified66.5%
if 6.7999999999999996e-306 < b Initial program 30.3%
*-commutative30.3%
Simplified30.3%
Taylor expanded in b around inf 71.6%
associate-*r/71.6%
mul-1-neg71.6%
Simplified71.6%
Final simplification68.8%
(FPCore (a b c) :precision binary64 (if (<= b 860000.0) (- (/ b a)) (/ c b)))
double code(double a, double b, double c) {
double tmp;
if (b <= 860000.0) {
tmp = -(b / a);
} else {
tmp = c / b;
}
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 <= 860000.0d0) then
tmp = -(b / a)
else
tmp = c / b
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double tmp;
if (b <= 860000.0) {
tmp = -(b / a);
} else {
tmp = c / b;
}
return tmp;
}
def code(a, b, c): tmp = 0 if b <= 860000.0: tmp = -(b / a) else: tmp = c / b return tmp
function code(a, b, c) tmp = 0.0 if (b <= 860000.0) tmp = Float64(-Float64(b / a)); else tmp = Float64(c / b); end return tmp end
function tmp_2 = code(a, b, c) tmp = 0.0; if (b <= 860000.0) tmp = -(b / a); else tmp = c / b; end tmp_2 = tmp; end
code[a_, b_, c_] := If[LessEqual[b, 860000.0], (-N[(b / a), $MachinePrecision]), N[(c / b), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 860000:\\
\;\;\;\;-\frac{b}{a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{b}\\
\end{array}
\end{array}
if b < 8.6e5Initial program 75.0%
*-commutative75.0%
Simplified75.0%
Taylor expanded in b around -inf 54.2%
mul-1-neg54.2%
Simplified54.2%
if 8.6e5 < b Initial program 14.5%
*-commutative14.5%
Simplified14.5%
Applied egg-rr3.6%
unpow-13.6%
Simplified3.6%
Taylor expanded in b around -inf 26.9%
(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(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 55.6%
*-commutative55.6%
Simplified55.6%
Applied egg-rr33.7%
unpow-133.7%
Simplified33.7%
Taylor expanded in b around -inf 10.7%
(FPCore (a b c) :precision binary64 (/ b a))
double code(double a, double b, double c) {
return b / 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 / a
end function
public static double code(double a, double b, double c) {
return b / a;
}
def code(a, b, c): return b / a
function code(a, b, c) return Float64(b / a) end
function tmp = code(a, b, c) tmp = b / a; end
code[a_, b_, c_] := N[(b / a), $MachinePrecision]
\begin{array}{l}
\\
\frac{b}{a}
\end{array}
Initial program 55.6%
*-commutative55.6%
Simplified55.6%
Applied egg-rr33.7%
unpow-133.7%
Simplified33.7%
Taylor expanded in a around 0 2.4%
(FPCore (a b c)
:precision binary64
(let* ((t_0 (sqrt (- (* b b) (* (* 4.0 a) c)))))
(if (< b 0.0)
(/ (+ (- b) t_0) (* 2.0 a))
(/ c (* a (/ (- (- b) t_0) (* 2.0 a)))))))
double code(double a, double b, double c) {
double t_0 = sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b < 0.0) {
tmp = (-b + t_0) / (2.0 * a);
} else {
tmp = c / (a * ((-b - t_0) / (2.0 * a)));
}
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) :: t_0
real(8) :: tmp
t_0 = sqrt(((b * b) - ((4.0d0 * a) * c)))
if (b < 0.0d0) then
tmp = (-b + t_0) / (2.0d0 * a)
else
tmp = c / (a * ((-b - t_0) / (2.0d0 * a)))
end if
code = tmp
end function
public static double code(double a, double b, double c) {
double t_0 = Math.sqrt(((b * b) - ((4.0 * a) * c)));
double tmp;
if (b < 0.0) {
tmp = (-b + t_0) / (2.0 * a);
} else {
tmp = c / (a * ((-b - t_0) / (2.0 * a)));
}
return tmp;
}
def code(a, b, c): t_0 = math.sqrt(((b * b) - ((4.0 * a) * c))) tmp = 0 if b < 0.0: tmp = (-b + t_0) / (2.0 * a) else: tmp = c / (a * ((-b - t_0) / (2.0 * a))) return tmp
function code(a, b, c) t_0 = sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c))) tmp = 0.0 if (b < 0.0) tmp = Float64(Float64(Float64(-b) + t_0) / Float64(2.0 * a)); else tmp = Float64(c / Float64(a * Float64(Float64(Float64(-b) - t_0) / Float64(2.0 * a)))); end return tmp end
function tmp_2 = code(a, b, c) t_0 = sqrt(((b * b) - ((4.0 * a) * c))); tmp = 0.0; if (b < 0.0) tmp = (-b + t_0) / (2.0 * a); else tmp = c / (a * ((-b - t_0) / (2.0 * a))); end tmp_2 = tmp; end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[Less[b, 0.0], N[(N[((-b) + t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision], N[(c / N[(a * N[(N[((-b) - t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}\\
\mathbf{if}\;b < 0:\\
\;\;\;\;\frac{\left(-b\right) + t\_0}{2 \cdot a}\\
\mathbf{else}:\\
\;\;\;\;\frac{c}{a \cdot \frac{\left(-b\right) - t\_0}{2 \cdot a}}\\
\end{array}
\end{array}
herbie shell --seed 2024100
(FPCore (a b c)
:name "The quadratic formula (r1)"
:precision binary64
:alt
(if (< b 0.0) (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)) (/ c (* a (/ (- (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))))
(/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))