
(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-define99.9%
Simplified99.9%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (if (or (<= (* x 0.5) -2e+24) (not (<= (* x 0.5) 2e-47))) (- (* x 0.5) (* y z)) (* y (+ (- 1.0 z) (log z)))))
double code(double x, double y, double z) {
double tmp;
if (((x * 0.5) <= -2e+24) || !((x * 0.5) <= 2e-47)) {
tmp = (x * 0.5) - (y * z);
} else {
tmp = y * ((1.0 - z) + 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 (((x * 0.5d0) <= (-2d+24)) .or. (.not. ((x * 0.5d0) <= 2d-47))) then
tmp = (x * 0.5d0) - (y * z)
else
tmp = y * ((1.0d0 - z) + log(z))
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (((x * 0.5) <= -2e+24) || !((x * 0.5) <= 2e-47)) {
tmp = (x * 0.5) - (y * z);
} else {
tmp = y * ((1.0 - z) + Math.log(z));
}
return tmp;
}
def code(x, y, z): tmp = 0 if ((x * 0.5) <= -2e+24) or not ((x * 0.5) <= 2e-47): tmp = (x * 0.5) - (y * z) else: tmp = y * ((1.0 - z) + math.log(z)) return tmp
function code(x, y, z) tmp = 0.0 if ((Float64(x * 0.5) <= -2e+24) || !(Float64(x * 0.5) <= 2e-47)) tmp = Float64(Float64(x * 0.5) - Float64(y * z)); else tmp = Float64(y * Float64(Float64(1.0 - z) + log(z))); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (((x * 0.5) <= -2e+24) || ~(((x * 0.5) <= 2e-47))) tmp = (x * 0.5) - (y * z); else tmp = y * ((1.0 - z) + log(z)); end tmp_2 = tmp; end
code[x_, y_, z_] := If[Or[LessEqual[N[(x * 0.5), $MachinePrecision], -2e+24], N[Not[LessEqual[N[(x * 0.5), $MachinePrecision], 2e-47]], $MachinePrecision]], N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision], N[(y * N[(N[(1.0 - z), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \cdot 0.5 \leq -2 \cdot 10^{+24} \lor \neg \left(x \cdot 0.5 \leq 2 \cdot 10^{-47}\right):\\
\;\;\;\;x \cdot 0.5 - y \cdot z\\
\mathbf{else}:\\
\;\;\;\;y \cdot \left(\left(1 - z\right) + \log z\right)\\
\end{array}
\end{array}
if (*.f64 x #s(literal 1/2 binary64)) < -2e24 or 1.9999999999999999e-47 < (*.f64 x #s(literal 1/2 binary64)) Initial program 100.0%
Taylor expanded in z around inf 90.2%
associate-*r*90.2%
mul-1-neg90.2%
Simplified90.2%
if -2e24 < (*.f64 x #s(literal 1/2 binary64)) < 1.9999999999999999e-47Initial program 99.9%
distribute-lft-in99.0%
Applied egg-rr99.0%
Taylor expanded in x around 0 84.9%
distribute-lft-out85.8%
Applied egg-rr85.8%
Final simplification88.0%
(FPCore (x y z) :precision binary64 (if (<= z 0.28) (+ (* x 0.5) (* y (+ 1.0 (log z)))) (- (* x 0.5) (* y z))))
double code(double x, double y, double z) {
double tmp;
if (z <= 0.28) {
tmp = (x * 0.5) + (y * (1.0 + log(z)));
} else {
tmp = (x * 0.5) - (y * 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 <= 0.28d0) then
tmp = (x * 0.5d0) + (y * (1.0d0 + log(z)))
else
tmp = (x * 0.5d0) - (y * z)
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (z <= 0.28) {
tmp = (x * 0.5) + (y * (1.0 + Math.log(z)));
} else {
tmp = (x * 0.5) - (y * z);
}
return tmp;
}
def code(x, y, z): tmp = 0 if z <= 0.28: tmp = (x * 0.5) + (y * (1.0 + math.log(z))) else: tmp = (x * 0.5) - (y * z) return tmp
function code(x, y, z) tmp = 0.0 if (z <= 0.28) tmp = Float64(Float64(x * 0.5) + Float64(y * Float64(1.0 + log(z)))); else tmp = Float64(Float64(x * 0.5) - Float64(y * z)); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (z <= 0.28) tmp = (x * 0.5) + (y * (1.0 + log(z))); else tmp = (x * 0.5) - (y * z); end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[z, 0.28], N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 0.28:\\
\;\;\;\;x \cdot 0.5 + y \cdot \left(1 + \log z\right)\\
\mathbf{else}:\\
\;\;\;\;x \cdot 0.5 - y \cdot z\\
\end{array}
\end{array}
if z < 0.28000000000000003Initial program 99.8%
Taylor expanded in z around 0 99.2%
if 0.28000000000000003 < z Initial program 100.0%
Taylor expanded in z around inf 97.9%
associate-*r*97.9%
mul-1-neg97.9%
Simplified97.9%
Final simplification98.5%
(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 (if (<= z 2.7e+38) (* x 0.5) (* y (- z))))
double code(double x, double y, double z) {
double tmp;
if (z <= 2.7e+38) {
tmp = x * 0.5;
} else {
tmp = y * -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 <= 2.7d+38) then
tmp = x * 0.5d0
else
tmp = y * -z
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (z <= 2.7e+38) {
tmp = x * 0.5;
} else {
tmp = y * -z;
}
return tmp;
}
def code(x, y, z): tmp = 0 if z <= 2.7e+38: tmp = x * 0.5 else: tmp = y * -z return tmp
function code(x, y, z) tmp = 0.0 if (z <= 2.7e+38) tmp = Float64(x * 0.5); else tmp = Float64(y * Float64(-z)); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (z <= 2.7e+38) tmp = x * 0.5; else tmp = y * -z; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[z, 2.7e+38], N[(x * 0.5), $MachinePrecision], N[(y * (-z)), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 2.7 \cdot 10^{+38}:\\
\;\;\;\;x \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;y \cdot \left(-z\right)\\
\end{array}
\end{array}
if z < 2.69999999999999996e38Initial program 99.8%
Taylor expanded in x around inf 49.6%
if 2.69999999999999996e38 < z Initial program 100.0%
Taylor expanded in z around inf 100.0%
associate-*r*100.0%
mul-1-neg100.0%
Simplified100.0%
Taylor expanded in x around inf 89.1%
mul-1-neg89.1%
unsub-neg89.1%
associate-/l*80.5%
Simplified80.5%
Taylor expanded in x around 0 76.6%
mul-1-neg76.6%
distribute-rgt-neg-out76.6%
Simplified76.6%
Final simplification61.5%
(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 75.3%
associate-*r*75.3%
mul-1-neg75.3%
Simplified75.3%
Final simplification75.3%
(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 38.7%
Final simplification38.7%
(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 2024067
(FPCore (x y z)
:name "System.Random.MWC.Distributions:gamma from mwc-random-0.13.3.2"
:precision binary64
:alt
(- (+ y (* 0.5 x)) (* y (- z (log z))))
(+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))