
(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 10 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
(if (<= (* x 0.5) -1e-112)
(- (* x 0.5) (* y z))
(if (<= (* x 0.5) 2e-36)
(* y (- (+ 1.0 (log z)) z))
(fma y (- z) (* x 0.5)))))
double code(double x, double y, double z) {
double tmp;
if ((x * 0.5) <= -1e-112) {
tmp = (x * 0.5) - (y * z);
} else if ((x * 0.5) <= 2e-36) {
tmp = y * ((1.0 + log(z)) - z);
} else {
tmp = fma(y, -z, (x * 0.5));
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (Float64(x * 0.5) <= -1e-112) tmp = Float64(Float64(x * 0.5) - Float64(y * z)); elseif (Float64(x * 0.5) <= 2e-36) tmp = Float64(y * Float64(Float64(1.0 + log(z)) - z)); else tmp = fma(y, Float64(-z), Float64(x * 0.5)); end return tmp end
code[x_, y_, z_] := If[LessEqual[N[(x * 0.5), $MachinePrecision], -1e-112], N[(N[(x * 0.5), $MachinePrecision] - N[(y * z), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(x * 0.5), $MachinePrecision], 2e-36], N[(y * N[(N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]), $MachinePrecision], N[(y * (-z) + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \cdot 0.5 \leq -1 \cdot 10^{-112}:\\
\;\;\;\;x \cdot 0.5 - y \cdot z\\
\mathbf{elif}\;x \cdot 0.5 \leq 2 \cdot 10^{-36}:\\
\;\;\;\;y \cdot \left(\left(1 + \log z\right) - z\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y, -z, x \cdot 0.5\right)\\
\end{array}
\end{array}
if (*.f64 x 1/2) < -9.9999999999999995e-113Initial program 99.9%
Taylor expanded in z around inf 85.7%
mul-1-neg85.7%
distribute-rgt-neg-out85.7%
Simplified85.7%
if -9.9999999999999995e-113 < (*.f64 x 1/2) < 1.9999999999999999e-36Initial program 99.9%
fma-def99.9%
+-commutative99.9%
associate-+r-99.9%
+-commutative99.9%
Simplified99.9%
fma-udef99.9%
+-commutative99.9%
associate-+r-99.9%
+-commutative99.9%
distribute-lft-in98.7%
associate-+r+98.7%
Applied egg-rr98.7%
Taylor expanded in y around inf 93.9%
if 1.9999999999999999e-36 < (*.f64 x 1/2) Initial program 100.0%
+-commutative100.0%
fma-def100.0%
Simplified100.0%
Taylor expanded in z around inf 92.9%
neg-mul-192.9%
Simplified92.9%
Final simplification90.7%
(FPCore (x y z) :precision binary64 (if (<= z 1.6e-14) (+ (* 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 <= 1.6e-14) {
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 <= 1.6e-14) 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, 1.6e-14], 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 1.6 \cdot 10^{-14}:\\
\;\;\;\;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 < 1.6000000000000001e-14Initial program 99.8%
Taylor expanded in z around 0 99.8%
if 1.6000000000000001e-14 < z Initial program 100.0%
+-commutative100.0%
fma-def100.0%
Simplified100.0%
Taylor expanded in z around inf 98.5%
neg-mul-198.5%
Simplified98.5%
Final simplification99.0%
(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 (- (+ 1.0 (log z)) z))))
double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 + log(z)) - 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 + log(z)) - z))
end function
public static double code(double x, double y, double z) {
return (x * 0.5) + (y * ((1.0 + Math.log(z)) - z));
}
def code(x, y, z): return (x * 0.5) + (y * ((1.0 + math.log(z)) - z))
function code(x, y, z) return Float64(Float64(x * 0.5) + Float64(y * Float64(Float64(1.0 + log(z)) - z))) end
function tmp = code(x, y, z) tmp = (x * 0.5) + (y * ((1.0 + log(z)) - z)); end
code[x_, y_, z_] := N[(N[(x * 0.5), $MachinePrecision] + N[(y * N[(N[(1.0 + N[Log[z], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 0.5 + y \cdot \left(\left(1 + \log z\right) - z\right)
\end{array}
Initial program 99.9%
Taylor expanded in y around 0 99.9%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (fma y (- z) (* x 0.5)))
double code(double x, double y, double z) {
return fma(y, -z, (x * 0.5));
}
function code(x, y, z) return fma(y, Float64(-z), Float64(x * 0.5)) end
code[x_, y_, z_] := N[(y * (-z) + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y, -z, x \cdot 0.5\right)
\end{array}
Initial program 99.9%
+-commutative99.9%
fma-def99.9%
Simplified99.9%
Taylor expanded in z around inf 82.5%
neg-mul-182.5%
Simplified82.5%
Final simplification82.5%
(FPCore (x y z) :precision binary64 (if (<= z 1.25e+25) (* x 0.5) (* y (- 1.0 z))))
double code(double x, double y, double z) {
double tmp;
if (z <= 1.25e+25) {
tmp = x * 0.5;
} else {
tmp = y * (1.0 - 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 <= 1.25d+25) then
tmp = x * 0.5d0
else
tmp = y * (1.0d0 - z)
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (z <= 1.25e+25) {
tmp = x * 0.5;
} else {
tmp = y * (1.0 - z);
}
return tmp;
}
def code(x, y, z): tmp = 0 if z <= 1.25e+25: tmp = x * 0.5 else: tmp = y * (1.0 - z) return tmp
function code(x, y, z) tmp = 0.0 if (z <= 1.25e+25) tmp = Float64(x * 0.5); else tmp = Float64(y * Float64(1.0 - z)); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (z <= 1.25e+25) tmp = x * 0.5; else tmp = y * (1.0 - z); end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[z, 1.25e+25], N[(x * 0.5), $MachinePrecision], N[(y * N[(1.0 - z), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 1.25 \cdot 10^{+25}:\\
\;\;\;\;x \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;y \cdot \left(1 - z\right)\\
\end{array}
\end{array}
if z < 1.25000000000000006e25Initial program 99.8%
Taylor expanded in x around inf 56.8%
if 1.25000000000000006e25 < z Initial program 100.0%
sub-neg100.0%
associate-+l+100.0%
distribute-rgt-in100.0%
*-lft-identity100.0%
associate-+r+100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
distribute-lft-neg-out100.0%
unsub-neg100.0%
fma-def100.0%
*-commutative100.0%
Simplified100.0%
Taylor expanded in z around inf 100.0%
Taylor expanded in x around 0 71.8%
*-rgt-identity71.8%
distribute-lft-out--71.8%
Simplified71.8%
Final simplification65.2%
(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 82.5%
mul-1-neg82.5%
distribute-rgt-neg-out82.5%
Simplified82.5%
Final simplification82.5%
(FPCore (x y z) :precision binary64 (if (<= z 4e+24) (* x 0.5) (* z (- y))))
double code(double x, double y, double z) {
double tmp;
if (z <= 4e+24) {
tmp = x * 0.5;
} else {
tmp = z * -y;
}
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+24) then
tmp = x * 0.5d0
else
tmp = z * -y
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (z <= 4e+24) {
tmp = x * 0.5;
} else {
tmp = z * -y;
}
return tmp;
}
def code(x, y, z): tmp = 0 if z <= 4e+24: tmp = x * 0.5 else: tmp = z * -y return tmp
function code(x, y, z) tmp = 0.0 if (z <= 4e+24) tmp = Float64(x * 0.5); else tmp = Float64(z * Float64(-y)); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (z <= 4e+24) tmp = x * 0.5; else tmp = z * -y; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[z, 4e+24], N[(x * 0.5), $MachinePrecision], N[(z * (-y)), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq 4 \cdot 10^{+24}:\\
\;\;\;\;x \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;z \cdot \left(-y\right)\\
\end{array}
\end{array}
if z < 3.9999999999999999e24Initial program 99.8%
Taylor expanded in x around inf 56.8%
if 3.9999999999999999e24 < z Initial program 100.0%
fma-def100.0%
+-commutative100.0%
associate-+r-100.0%
+-commutative100.0%
Simplified100.0%
fma-udef100.0%
+-commutative100.0%
associate-+r-100.0%
+-commutative100.0%
distribute-lft-in99.3%
associate-+r+99.3%
Applied egg-rr99.3%
Taylor expanded in z around inf 71.8%
mul-1-neg71.8%
distribute-rgt-neg-out71.8%
Simplified71.8%
Final simplification65.2%
(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 41.7%
Final simplification41.7%
(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 2023274
(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)))))