
(FPCore (x y z) :precision binary64 (+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))
double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + log(z)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * 0.5d0) + (y * ((1.0d0 - z) + log(z)))
end function
public static double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + Math.log(z)));
}
def code(x, y, z): return (x * 0.5) + (y * ((1.0 - z) + math.log(z)))
function code(x, y, z) return Float64(Float64(x * 0.5) + Float64(y * Float64(Float64(1.0 - z) + log(z)))) end
function tmp = code(x, y, z) tmp = (x * 0.5) + (y * ((1.0 - z) + log(z))); end
code[x_, y_, z_] := N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(N[(1.0 - z), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5 + y \cdot \left(\left(1 - z\right) + \log z\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z) :precision binary64 (+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))
double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + log(z)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * 0.5d0) + (y * ((1.0d0 - z) + log(z)))
end function
public static double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + Math.log(z)));
}
def code(x, y, z): return (x * 0.5) + (y * ((1.0 - z) + math.log(z)))
function code(x, y, z) return Float64(Float64(x * 0.5) + Float64(y * Float64(Float64(1.0 - z) + log(z)))) end
function tmp = code(x, y, z) tmp = (x * 0.5) + (y * ((1.0 - z) + log(z))); end
code[x_, y_, z_] := N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(N[(1.0 - z), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5 + y \cdot \left(\left(1 - z\right) + \log z\right)
\end{array}
(FPCore (x y z) :precision binary64 (fma y (+ (- 1.0 z) (log z)) (* x 0.5)))
double code(double x, double y, double z) {
return fma(y, ((1.0 - z) + log(z)), (x * 0.5));
}
function code(x, y, z) return fma(y, Float64(Float64(1.0 - z) + log(z)), Float64(x * 0.5)) end
code[x_, y_, z_] := N[(y * N[(N[(1.0 - z), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y, \left(1 - z\right) + \log z, x \cdot 0.5\right)
\end{array}
Initial program 99.9%
+-commutative99.9%
fma-def99.9%
Simplified99.9%
Final simplification99.9%
(FPCore (x y z)
:precision binary64
(let* ((t_0 (* y (+ 1.0 (log z)))) (t_1 (- (* x 0.5) (* y z))))
(if (<= z 7.6e-172)
t_1
(if (<= z 2.25e-88)
t_0
(if (<= z 1e-39)
t_1
(if (<= z 4.5e-12) t_0 (fma y (- z) (* x 0.5))))))))
double code(double x, double y, double z) {
double t_0 = y * (1.0 + log(z));
double t_1 = (x * 0.5) - (y * z);
double tmp;
if (z <= 7.6e-172) {
tmp = t_1;
} else if (z <= 2.25e-88) {
tmp = t_0;
} else if (z <= 1e-39) {
tmp = t_1;
} else if (z <= 4.5e-12) {
tmp = t_0;
} else {
tmp = fma(y, -z, (x * 0.5));
}
return tmp;
}
function code(x, y, z) t_0 = Float64(y * Float64(1.0 + log(z))) t_1 = Float64(Float64(x * 0.5) - Float64(y * z)) tmp = 0.0 if (z <= 7.6e-172) tmp = t_1; elseif (z <= 2.25e-88) tmp = t_0; elseif (z <= 1e-39) tmp = t_1; elseif (z <= 4.5e-12) tmp = t_0; else tmp = fma(y, Float64(-z), Float64(x * 0.5)); end return tmp end
code[x_, y_, z_] := Block[{t$95$0 = N[(y * N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[z, 7.6e-172], t$95$1, If[LessEqual[z, 2.25e-88], t$95$0, If[LessEqual[z, 1e-39], t$95$1, If[LessEqual[z, 4.5e-12], t$95$0, N[(y * (-z) + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := y \cdot \left(1 + \log z\right)\\
t_1 := x \cdot 0.5 - y \cdot z\\
\mathbf{if}\;z \leq 7.6 \cdot 10^{-172}:\\
\;\;\;\;t\_1\\
\mathbf{elif}\;z \leq 2.25 \cdot 10^{-88}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;z \leq 10^{-39}:\\
\;\;\;\;t\_1\\
\mathbf{elif}\;z \leq 4.5 \cdot 10^{-12}:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y, -z, x \cdot 0.5\right)\\
\end{array}
\end{array}
if z < 7.59999999999999974e-172 or 2.24999999999999996e-88 < z < 9.99999999999999929e-40Initial program 99.8%
Taylor expanded in z around inf 68.1%
mul-1-neg68.1%
*-commutative68.1%
distribute-rgt-neg-in68.1%
Simplified68.1%
distribute-rgt-neg-out68.1%
unsub-neg68.1%
Applied egg-rr68.1%
if 7.59999999999999974e-172 < z < 2.24999999999999996e-88 or 9.99999999999999929e-40 < z < 4.49999999999999981e-12Initial program 99.7%
Taylor expanded in z around 0 99.2%
Taylor expanded in x around 0 73.6%
if 4.49999999999999981e-12 < z Initial program 100.0%
+-commutative100.0%
fma-def100.0%
Simplified100.0%
Taylor expanded in z around inf 97.6%
mul-1-neg97.6%
Simplified97.6%
Final simplification84.1%
(FPCore (x y z)
:precision binary64
(if (or (<= z 4e-167)
(and (not (<= z 1.35e-88)) (or (<= z 4.5e-39) (not (<= z 4.5e-12)))))
(- (* x 0.5) (* y z))
(* y (+ 1.0 (log z)))))
double code(double x, double y, double z) {
double tmp;
if ((z <= 4e-167) || (!(z <= 1.35e-88) && ((z <= 4.5e-39) || !(z <= 4.5e-12)))) {
tmp = (x * 0.5) - (y * z);
} else {
tmp = y * (1.0 + log(z));
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if ((z <= 4d-167) .or. (.not. (z <= 1.35d-88)) .and. (z <= 4.5d-39) .or. (.not. (z <= 4.5d-12))) then
tmp = (x * 0.5d0) - (y * z)
else
tmp = y * (1.0d0 + log(z))
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if ((z <= 4e-167) || (!(z <= 1.35e-88) && ((z <= 4.5e-39) || !(z <= 4.5e-12)))) {
tmp = (x * 0.5) - (y * z);
} else {
tmp = y * (1.0 + Math.log(z));
}
return tmp;
}
def code(x, y, z): tmp = 0 if (z <= 4e-167) or (not (z <= 1.35e-88) and ((z <= 4.5e-39) or not (z <= 4.5e-12))): tmp = (x * 0.5) - (y * z) else: tmp = y * (1.0 + math.log(z)) return tmp
function code(x, y, z) tmp = 0.0 if ((z <= 4e-167) || (!(z <= 1.35e-88) && ((z <= 4.5e-39) || !(z <= 4.5e-12)))) tmp = Float64(Float64(x * 0.5) - Float64(y * z)); else tmp = Float64(y * Float64(1.0 + log(z))); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if ((z <= 4e-167) || (~((z <= 1.35e-88)) && ((z <= 4.5e-39) || ~((z <= 4.5e-12))))) tmp = (x * 0.5) - (y * z); else tmp = y * (1.0 + log(z)); end tmp_2 = tmp; end
code[x_, y_, z_] := If[Or[LessEqual[z, 4e-167], And[N[Not[LessEqual[z, 1.35e-88]], $MachinePrecision], Or[LessEqual[z, 4.5e-39], N[Not[LessEqual[z, 4.5e-12]], $MachinePrecision]]]], N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision], N[(y * N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 4 \cdot 10^{-167} \lor \neg \left(z \leq 1.35 \cdot 10^{-88}\right) \land \left(z \leq 4.5 \cdot 10^{-39} \lor \neg \left(z \leq 4.5 \cdot 10^{-12}\right)\right):\\
\;\;\;\;x \cdot 0.5 - y \cdot z\\
\mathbf{else}:\\
\;\;\;\;y \cdot \left(1 + \log z\right)\\
\end{array}
\end{array}
if z < 4.00000000000000001e-167 or 1.34999999999999997e-88 < z < 4.5000000000000001e-39 or 4.49999999999999981e-12 < z Initial program 99.9%
Taylor expanded in z around inf 86.2%
mul-1-neg86.2%
*-commutative86.2%
distribute-rgt-neg-in86.2%
Simplified86.2%
distribute-rgt-neg-out86.2%
unsub-neg86.2%
Applied egg-rr86.2%
if 4.00000000000000001e-167 < z < 1.34999999999999997e-88 or 4.5000000000000001e-39 < z < 4.49999999999999981e-12Initial program 99.7%
Taylor expanded in z around 0 99.2%
Taylor expanded in x around 0 73.6%
Final simplification84.1%
(FPCore (x y z) :precision binary64 (if (<= z 0.00075) (+ (* x 0.5) (* y (+ 1.0 (log z)))) (fma y (- z) (* x 0.5))))
double code(double x, double y, double z) {
double tmp;
if (z <= 0.00075) {
tmp = (x * 0.5) + (y * (1.0 + log(z)));
} else {
tmp = fma(y, -z, (x * 0.5));
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (z <= 0.00075) tmp = Float64(Float64(x * 0.5) + Float64(y * Float64(1.0 + log(z)))); else tmp = fma(y, Float64(-z), Float64(x * 0.5)); end return tmp end
code[x_, y_, z_] := If[LessEqual[z, 0.00075], N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(y * (-z) + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 0.00075:\\
\;\;\;\;x \cdot 0.5 + y \cdot \left(1 + \log z\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y, -z, x \cdot 0.5\right)\\
\end{array}
\end{array}
if z < 7.5000000000000002e-4Initial program 99.8%
Taylor expanded in z around 0 99.3%
if 7.5000000000000002e-4 < z Initial program 100.0%
+-commutative100.0%
fma-def100.0%
Simplified100.0%
Taylor expanded in z around inf 98.2%
mul-1-neg98.2%
Simplified98.2%
Final simplification98.8%
(FPCore (x y z) :precision binary64 (+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))
double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + log(z)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * 0.5d0) + (y * ((1.0d0 - z) + log(z)))
end function
public static double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 - z) + Math.log(z)));
}
def code(x, y, z): return (x * 0.5) + (y * ((1.0 - z) + math.log(z)))
function code(x, y, z) return Float64(Float64(x * 0.5) + Float64(y * Float64(Float64(1.0 - z) + log(z)))) end
function tmp = code(x, y, z) tmp = (x * 0.5) + (y * ((1.0 - z) + log(z))); end
code[x_, y_, z_] := N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(N[(1.0 - z), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5 + y \cdot \left(\left(1 - z\right) + \log z\right)
\end{array}
Initial program 99.9%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (- (* x 0.5) (* y z)))
double code(double x, double y, double z) {
return (x * 0.5) - (y * z);
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * 0.5d0) - (y * z)
end function
public static double code(double x, double y, double z) {
return (x * 0.5) - (y * z);
}
def code(x, y, z): return (x * 0.5) - (y * z)
function code(x, y, z) return Float64(Float64(x * 0.5) - Float64(y * z)) end
function tmp = code(x, y, z) tmp = (x * 0.5) - (y * z); end
code[x_, y_, z_] := N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5 - y \cdot z
\end{array}
Initial program 99.9%
Taylor expanded in z around inf 76.7%
mul-1-neg76.7%
*-commutative76.7%
distribute-rgt-neg-in76.7%
Simplified76.7%
distribute-rgt-neg-out76.7%
unsub-neg76.7%
Applied egg-rr76.7%
Final simplification76.7%
(FPCore (x y z) :precision binary64 (* x 0.5))
double code(double x, double y, double z) {
return x * 0.5;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = x * 0.5d0
end function
public static double code(double x, double y, double z) {
return x * 0.5;
}
def code(x, y, z): return x * 0.5
function code(x, y, z) return Float64(x * 0.5) end
function tmp = code(x, y, z) tmp = x * 0.5; end
code[x_, y_, z_] := N[(x * 0.5), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5
\end{array}
Initial program 99.9%
Taylor expanded in x around inf 42.8%
Final simplification42.8%
(FPCore (x y z) :precision binary64 (- (+ y (* 0.5 x)) (* y (- z (log z)))))
double code(double x, double y, double z) {
return (y + (0.5 * x)) - (y * (z - log(z)));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (y + (0.5d0 * x)) - (y * (z - log(z)))
end function
public static double code(double x, double y, double z) {
return (y + (0.5 * x)) - (y * (z - Math.log(z)));
}
def code(x, y, z): return (y + (0.5 * x)) - (y * (z - math.log(z)))
function code(x, y, z) return Float64(Float64(y + Float64(0.5 * x)) - Float64(y * Float64(z - log(z)))) end
function tmp = code(x, y, z) tmp = (y + (0.5 * x)) - (y * (z - log(z))); end
code[x_, y_, z_] := N[(N[(y + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - N[(y * N[(z - N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(y + 0.5 \cdot x\right) - y \cdot \left(z - \log z\right)
\end{array}
herbie shell --seed 2024027
(FPCore (x y z)
:name "System.Random.MWC.Distributions:gamma from mwc-random-0.13.3.2"
:precision binary64
:herbie-target
(- (+ y (* 0.5 x)) (* y (- z (log z))))
(+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))