
(FPCore (x y z t) :precision binary64 (- x (/ (* (* y 2.0) z) (- (* (* z 2.0) z) (* y t)))))
double code(double x, double y, double z, double t) {
return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)));
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = x - (((y * 2.0d0) * z) / (((z * 2.0d0) * z) - (y * t)))
end function
public static double code(double x, double y, double z, double t) {
return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)));
}
def code(x, y, z, t): return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)))
function code(x, y, z, t) return Float64(x - Float64(Float64(Float64(y * 2.0) * z) / Float64(Float64(Float64(z * 2.0) * z) - Float64(y * t)))) end
function tmp = code(x, y, z, t) tmp = x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t))); end
code[x_, y_, z_, t_] := N[(x - N[(N[(N[(y * 2.0), $MachinePrecision] * z), $MachinePrecision] / N[(N[(N[(z * 2.0), $MachinePrecision] * z), $MachinePrecision] - N[(y * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{\left(y \cdot 2\right) \cdot z}{\left(z \cdot 2\right) \cdot z - y \cdot t}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z t) :precision binary64 (- x (/ (* (* y 2.0) z) (- (* (* z 2.0) z) (* y t)))))
double code(double x, double y, double z, double t) {
return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)));
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = x - (((y * 2.0d0) * z) / (((z * 2.0d0) * z) - (y * t)))
end function
public static double code(double x, double y, double z, double t) {
return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)));
}
def code(x, y, z, t): return x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t)))
function code(x, y, z, t) return Float64(x - Float64(Float64(Float64(y * 2.0) * z) / Float64(Float64(Float64(z * 2.0) * z) - Float64(y * t)))) end
function tmp = code(x, y, z, t) tmp = x - (((y * 2.0) * z) / (((z * 2.0) * z) - (y * t))); end
code[x_, y_, z_, t_] := N[(x - N[(N[(N[(y * 2.0), $MachinePrecision] * z), $MachinePrecision] / N[(N[(N[(z * 2.0), $MachinePrecision] * z), $MachinePrecision] - N[(y * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{\left(y \cdot 2\right) \cdot z}{\left(z \cdot 2\right) \cdot z - y \cdot t}
\end{array}
(FPCore (x y z t) :precision binary64 (- x (/ (* y 2.0) (- (* 2.0 z) (* y (/ t z))))))
double code(double x, double y, double z, double t) {
return x - ((y * 2.0) / ((2.0 * z) - (y * (t / z))));
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = x - ((y * 2.0d0) / ((2.0d0 * z) - (y * (t / z))))
end function
public static double code(double x, double y, double z, double t) {
return x - ((y * 2.0) / ((2.0 * z) - (y * (t / z))));
}
def code(x, y, z, t): return x - ((y * 2.0) / ((2.0 * z) - (y * (t / z))))
function code(x, y, z, t) return Float64(x - Float64(Float64(y * 2.0) / Float64(Float64(2.0 * z) - Float64(y * Float64(t / z))))) end
function tmp = code(x, y, z, t) tmp = x - ((y * 2.0) / ((2.0 * z) - (y * (t / z)))); end
code[x_, y_, z_, t_] := N[(x - N[(N[(y * 2.0), $MachinePrecision] / N[(N[(2.0 * z), $MachinePrecision] - N[(y * N[(t / z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{y \cdot 2}{2 \cdot z - y \cdot \frac{t}{z}}
\end{array}
Initial program 85.3%
associate-/l*92.9%
associate-*l*92.9%
Simplified92.9%
Taylor expanded in z around 0 95.3%
+-commutative95.3%
mul-1-neg95.3%
*-commutative95.3%
associate-*r/98.1%
unsub-neg98.1%
*-commutative98.1%
Simplified98.1%
Final simplification98.1%
(FPCore (x y z t) :precision binary64 (if (or (<= z -3000000.0) (not (<= z 2.6e-32))) (- x (/ y z)) (+ x (* z (/ 2.0 t)))))
double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -3000000.0) || !(z <= 2.6e-32)) {
tmp = x - (y / z);
} else {
tmp = x + (z * (2.0 / t));
}
return tmp;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if ((z <= (-3000000.0d0)) .or. (.not. (z <= 2.6d-32))) then
tmp = x - (y / z)
else
tmp = x + (z * (2.0d0 / t))
end if
code = tmp
end function
public static double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -3000000.0) || !(z <= 2.6e-32)) {
tmp = x - (y / z);
} else {
tmp = x + (z * (2.0 / t));
}
return tmp;
}
def code(x, y, z, t): tmp = 0 if (z <= -3000000.0) or not (z <= 2.6e-32): tmp = x - (y / z) else: tmp = x + (z * (2.0 / t)) return tmp
function code(x, y, z, t) tmp = 0.0 if ((z <= -3000000.0) || !(z <= 2.6e-32)) tmp = Float64(x - Float64(y / z)); else tmp = Float64(x + Float64(z * Float64(2.0 / t))); end return tmp end
function tmp_2 = code(x, y, z, t) tmp = 0.0; if ((z <= -3000000.0) || ~((z <= 2.6e-32))) tmp = x - (y / z); else tmp = x + (z * (2.0 / t)); end tmp_2 = tmp; end
code[x_, y_, z_, t_] := If[Or[LessEqual[z, -3000000.0], N[Not[LessEqual[z, 2.6e-32]], $MachinePrecision]], N[(x - N[(y / z), $MachinePrecision]), $MachinePrecision], N[(x + N[(z * N[(2.0 / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq -3000000 \lor \neg \left(z \leq 2.6 \cdot 10^{-32}\right):\\
\;\;\;\;x - \frac{y}{z}\\
\mathbf{else}:\\
\;\;\;\;x + z \cdot \frac{2}{t}\\
\end{array}
\end{array}
if z < -3e6 or 2.5999999999999997e-32 < z Initial program 74.3%
sub-neg74.3%
associate-/l*92.3%
distribute-neg-frac92.3%
distribute-lft-neg-out92.3%
associate-/r/92.3%
distribute-lft-neg-out92.3%
distribute-rgt-neg-in92.3%
metadata-eval92.3%
*-commutative92.3%
associate-*l*92.3%
fma-neg92.3%
Simplified92.3%
Taylor expanded in y around 0 93.9%
mul-1-neg93.9%
sub-neg93.9%
Simplified93.9%
if -3e6 < z < 2.5999999999999997e-32Initial program 95.4%
sub-neg95.4%
associate-/l*93.4%
distribute-neg-frac93.4%
distribute-lft-neg-out93.4%
associate-/r/96.2%
distribute-lft-neg-out96.2%
distribute-rgt-neg-in96.2%
metadata-eval96.2%
*-commutative96.2%
associate-*l*96.2%
fma-neg96.2%
Simplified96.2%
Taylor expanded in y around inf 94.1%
Final simplification94.0%
(FPCore (x y z t) :precision binary64 (if (or (<= z -2900000.0) (not (<= z 2.6e-32))) (- x (/ y z)) (- x (* (/ z t) -2.0))))
double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2900000.0) || !(z <= 2.6e-32)) {
tmp = x - (y / z);
} else {
tmp = x - ((z / t) * -2.0);
}
return tmp;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if ((z <= (-2900000.0d0)) .or. (.not. (z <= 2.6d-32))) then
tmp = x - (y / z)
else
tmp = x - ((z / t) * (-2.0d0))
end if
code = tmp
end function
public static double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2900000.0) || !(z <= 2.6e-32)) {
tmp = x - (y / z);
} else {
tmp = x - ((z / t) * -2.0);
}
return tmp;
}
def code(x, y, z, t): tmp = 0 if (z <= -2900000.0) or not (z <= 2.6e-32): tmp = x - (y / z) else: tmp = x - ((z / t) * -2.0) return tmp
function code(x, y, z, t) tmp = 0.0 if ((z <= -2900000.0) || !(z <= 2.6e-32)) tmp = Float64(x - Float64(y / z)); else tmp = Float64(x - Float64(Float64(z / t) * -2.0)); end return tmp end
function tmp_2 = code(x, y, z, t) tmp = 0.0; if ((z <= -2900000.0) || ~((z <= 2.6e-32))) tmp = x - (y / z); else tmp = x - ((z / t) * -2.0); end tmp_2 = tmp; end
code[x_, y_, z_, t_] := If[Or[LessEqual[z, -2900000.0], N[Not[LessEqual[z, 2.6e-32]], $MachinePrecision]], N[(x - N[(y / z), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[(z / t), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq -2900000 \lor \neg \left(z \leq 2.6 \cdot 10^{-32}\right):\\
\;\;\;\;x - \frac{y}{z}\\
\mathbf{else}:\\
\;\;\;\;x - \frac{z}{t} \cdot -2\\
\end{array}
\end{array}
if z < -2.9e6 or 2.5999999999999997e-32 < z Initial program 74.3%
sub-neg74.3%
associate-/l*92.3%
distribute-neg-frac92.3%
distribute-lft-neg-out92.3%
associate-/r/92.3%
distribute-lft-neg-out92.3%
distribute-rgt-neg-in92.3%
metadata-eval92.3%
*-commutative92.3%
associate-*l*92.3%
fma-neg92.3%
Simplified92.3%
Taylor expanded in y around 0 93.9%
mul-1-neg93.9%
sub-neg93.9%
Simplified93.9%
if -2.9e6 < z < 2.5999999999999997e-32Initial program 95.4%
associate-/l*93.4%
associate-*l*93.4%
Simplified93.4%
Taylor expanded in y around inf 94.2%
*-commutative94.2%
Simplified94.2%
Final simplification94.0%
(FPCore (x y z t) :precision binary64 (if (or (<= z -2e+64) (not (<= z 4.3e-63))) (- x (/ y z)) x))
double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2e+64) || !(z <= 4.3e-63)) {
tmp = x - (y / z);
} else {
tmp = x;
}
return tmp;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if ((z <= (-2d+64)) .or. (.not. (z <= 4.3d-63))) then
tmp = x - (y / z)
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2e+64) || !(z <= 4.3e-63)) {
tmp = x - (y / z);
} else {
tmp = x;
}
return tmp;
}
def code(x, y, z, t): tmp = 0 if (z <= -2e+64) or not (z <= 4.3e-63): tmp = x - (y / z) else: tmp = x return tmp
function code(x, y, z, t) tmp = 0.0 if ((z <= -2e+64) || !(z <= 4.3e-63)) tmp = Float64(x - Float64(y / z)); else tmp = x; end return tmp end
function tmp_2 = code(x, y, z, t) tmp = 0.0; if ((z <= -2e+64) || ~((z <= 4.3e-63))) tmp = x - (y / z); else tmp = x; end tmp_2 = tmp; end
code[x_, y_, z_, t_] := If[Or[LessEqual[z, -2e+64], N[Not[LessEqual[z, 4.3e-63]], $MachinePrecision]], N[(x - N[(y / z), $MachinePrecision]), $MachinePrecision], x]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq -2 \cdot 10^{+64} \lor \neg \left(z \leq 4.3 \cdot 10^{-63}\right):\\
\;\;\;\;x - \frac{y}{z}\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if z < -2.00000000000000004e64 or 4.2999999999999999e-63 < z Initial program 75.5%
sub-neg75.5%
associate-/l*92.4%
distribute-neg-frac92.4%
distribute-lft-neg-out92.4%
associate-/r/92.4%
distribute-lft-neg-out92.4%
distribute-rgt-neg-in92.4%
metadata-eval92.4%
*-commutative92.4%
associate-*l*92.4%
fma-neg92.4%
Simplified92.4%
Taylor expanded in y around 0 93.5%
mul-1-neg93.5%
sub-neg93.5%
Simplified93.5%
if -2.00000000000000004e64 < z < 4.2999999999999999e-63Initial program 94.7%
sub-neg94.7%
associate-/l*93.3%
distribute-neg-frac93.3%
distribute-lft-neg-out93.3%
associate-/r/96.2%
distribute-lft-neg-out96.2%
distribute-rgt-neg-in96.2%
metadata-eval96.2%
*-commutative96.2%
associate-*l*96.2%
fma-neg96.2%
Simplified96.2%
Taylor expanded in x around inf 80.8%
Final simplification87.0%
(FPCore (x y z t) :precision binary64 x)
double code(double x, double y, double z, double t) {
return x;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = x
end function
public static double code(double x, double y, double z, double t) {
return x;
}
def code(x, y, z, t): return x
function code(x, y, z, t) return x end
function tmp = code(x, y, z, t) tmp = x; end
code[x_, y_, z_, t_] := x
\begin{array}{l}
\\
x
\end{array}
Initial program 85.3%
sub-neg85.3%
associate-/l*92.9%
distribute-neg-frac92.9%
distribute-lft-neg-out92.9%
associate-/r/94.4%
distribute-lft-neg-out94.4%
distribute-rgt-neg-in94.4%
metadata-eval94.4%
*-commutative94.4%
associate-*l*94.4%
fma-neg94.4%
Simplified94.4%
Taylor expanded in x around inf 80.6%
Final simplification80.6%
(FPCore (x y z t) :precision binary64 (- x (/ 1.0 (- (/ z y) (/ (/ t 2.0) z)))))
double code(double x, double y, double z, double t) {
return x - (1.0 / ((z / y) - ((t / 2.0) / z)));
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = x - (1.0d0 / ((z / y) - ((t / 2.0d0) / z)))
end function
public static double code(double x, double y, double z, double t) {
return x - (1.0 / ((z / y) - ((t / 2.0) / z)));
}
def code(x, y, z, t): return x - (1.0 / ((z / y) - ((t / 2.0) / z)))
function code(x, y, z, t) return Float64(x - Float64(1.0 / Float64(Float64(z / y) - Float64(Float64(t / 2.0) / z)))) end
function tmp = code(x, y, z, t) tmp = x - (1.0 / ((z / y) - ((t / 2.0) / z))); end
code[x_, y_, z_, t_] := N[(x - N[(1.0 / N[(N[(z / y), $MachinePrecision] - N[(N[(t / 2.0), $MachinePrecision] / z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x - \frac{1}{\frac{z}{y} - \frac{\frac{t}{2}}{z}}
\end{array}
herbie shell --seed 2023271
(FPCore (x y z t)
:name "Numeric.AD.Rank1.Halley:findZero from ad-4.2.4"
:precision binary64
:herbie-target
(- x (/ 1.0 (- (/ z y) (/ (/ t 2.0) z))))
(- x (/ (* (* y 2.0) z) (- (* (* z 2.0) z) (* y t)))))