
(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 (- (log z) z) (fma 0.5 x y)))
double code(double x, double y, double z) {
return fma(y, (log(z) - z), fma(0.5, x, y));
}
function code(x, y, z) return fma(y, Float64(log(z) - z), fma(0.5, x, y)) end
code[x_, y_, z_] := N[(y * N[(N[Log[z], $MachinePrecision] - z), $MachinePrecision] + N[(0.5 * x + y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y, \log z - z, \mathsf{fma}\left(0.5, x, y\right)\right)
\end{array}
Initial program 99.9%
Taylor expanded in x around 0
sub-negN/A
associate-+r+N/A
mul-1-negN/A
distribute-lft-inN/A
*-rgt-identityN/A
associate-+r+N/A
+-commutativeN/A
lower-fma.f64N/A
mul-1-negN/A
sub-negN/A
lower--.f64N/A
lower-log.f64N/A
lower-fma.f6499.9
Applied rewrites99.9%
(FPCore (x y z) :precision binary64 (let* ((t_0 (* y (+ (log z) (- 1.0 z)))) (t_1 (- (* y z)))) (if (<= t_0 -5e+69) t_1 (if (<= t_0 5e+62) (* 0.5 x) t_1))))
double code(double x, double y, double z) {
double t_0 = y * (log(z) + (1.0 - z));
double t_1 = -(y * z);
double tmp;
if (t_0 <= -5e+69) {
tmp = t_1;
} else if (t_0 <= 5e+62) {
tmp = 0.5 * x;
} else {
tmp = t_1;
}
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) :: t_0
real(8) :: t_1
real(8) :: tmp
t_0 = y * (log(z) + (1.0d0 - z))
t_1 = -(y * z)
if (t_0 <= (-5d+69)) then
tmp = t_1
else if (t_0 <= 5d+62) then
tmp = 0.5d0 * x
else
tmp = t_1
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double t_0 = y * (Math.log(z) + (1.0 - z));
double t_1 = -(y * z);
double tmp;
if (t_0 <= -5e+69) {
tmp = t_1;
} else if (t_0 <= 5e+62) {
tmp = 0.5 * x;
} else {
tmp = t_1;
}
return tmp;
}
def code(x, y, z): t_0 = y * (math.log(z) + (1.0 - z)) t_1 = -(y * z) tmp = 0 if t_0 <= -5e+69: tmp = t_1 elif t_0 <= 5e+62: tmp = 0.5 * x else: tmp = t_1 return tmp
function code(x, y, z) t_0 = Float64(y * Float64(log(z) + Float64(1.0 - z))) t_1 = Float64(-Float64(y * z)) tmp = 0.0 if (t_0 <= -5e+69) tmp = t_1; elseif (t_0 <= 5e+62) tmp = Float64(0.5 * x); else tmp = t_1; end return tmp end
function tmp_2 = code(x, y, z) t_0 = y * (log(z) + (1.0 - z)); t_1 = -(y * z); tmp = 0.0; if (t_0 <= -5e+69) tmp = t_1; elseif (t_0 <= 5e+62) tmp = 0.5 * x; else tmp = t_1; end tmp_2 = tmp; end
code[x_, y_, z_] := Block[{t$95$0 = N[(y * N[(N[Log[z], $MachinePrecision] + N[(1.0 - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = (-N[(y * z), $MachinePrecision])}, If[LessEqual[t$95$0, -5e+69], t$95$1, If[LessEqual[t$95$0, 5e+62], N[(0.5 * x), $MachinePrecision], t$95$1]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := y \cdot \left(\log z + \left(1 - z\right)\right)\\
t_1 := -y \cdot z\\
\mathbf{if}\;t\_0 \leq -5 \cdot 10^{+69}:\\
\;\;\;\;t\_1\\
\mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+62}:\\
\;\;\;\;0.5 \cdot x\\
\mathbf{else}:\\
\;\;\;\;t\_1\\
\end{array}
\end{array}
if (*.f64 y (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z))) < -5.00000000000000036e69 or 5.00000000000000029e62 < (*.f64 y (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z))) Initial program 99.9%
Taylor expanded in z around inf
mul-1-negN/A
distribute-rgt-neg-inN/A
lower-*.f64N/A
lower-neg.f6462.2
Applied rewrites62.2%
if -5.00000000000000036e69 < (*.f64 y (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z))) < 5.00000000000000029e62Initial program 99.9%
Taylor expanded in x around inf
lower-*.f6467.7
Applied rewrites67.7%
Final simplification64.8%
(FPCore (x y z) :precision binary64 (if (<= (+ (log z) (- 1.0 z)) -2000.0) (fma z (- (/ y z) y) (* 0.5 x)) (fma y (log z) (fma 0.5 x y))))
double code(double x, double y, double z) {
double tmp;
if ((log(z) + (1.0 - z)) <= -2000.0) {
tmp = fma(z, ((y / z) - y), (0.5 * x));
} else {
tmp = fma(y, log(z), fma(0.5, x, y));
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (Float64(log(z) + Float64(1.0 - z)) <= -2000.0) tmp = fma(z, Float64(Float64(y / z) - y), Float64(0.5 * x)); else tmp = fma(y, log(z), fma(0.5, x, y)); end return tmp end
code[x_, y_, z_] := If[LessEqual[N[(N[Log[z], $MachinePrecision] + N[(1.0 - z), $MachinePrecision]), $MachinePrecision], -2000.0], N[(z * N[(N[(y / z), $MachinePrecision] - y), $MachinePrecision] + N[(0.5 * x), $MachinePrecision]), $MachinePrecision], N[(y * N[Log[z], $MachinePrecision] + N[(0.5 * x + y), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\log z + \left(1 - z\right) \leq -2000:\\
\;\;\;\;\mathsf{fma}\left(z, \frac{y}{z} - y, 0.5 \cdot x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y, \log z, \mathsf{fma}\left(0.5, x, y\right)\right)\\
\end{array}
\end{array}
if (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z)) < -2e3Initial program 100.0%
lift-*.f64N/A
lift--.f64N/A
lift-log.f64N/A
lift-+.f64N/A
lift-*.f64N/A
+-commutativeN/A
lift-*.f64N/A
lift-+.f64N/A
distribute-rgt-inN/A
associate-+l+N/A
lower-fma.f64N/A
*-commutativeN/A
lower-fma.f64100.0
Applied rewrites100.0%
Taylor expanded in y around 0
lower-*.f6497.8
Applied rewrites97.8%
Taylor expanded in z around inf
+-commutativeN/A
associate-+r+N/A
distribute-lft-inN/A
*-commutativeN/A
associate-*r/N/A
associate-*l/N/A
associate-/l*N/A
*-rgt-identityN/A
associate-*r/N/A
rgt-mult-inverseN/A
*-rgt-identityN/A
lower-fma.f64N/A
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
lower--.f64N/A
lower-/.f64N/A
lower-*.f6497.8
Applied rewrites97.8%
if -2e3 < (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z)) Initial program 99.8%
Taylor expanded in z around 0
distribute-lft-inN/A
*-rgt-identityN/A
associate-+r+N/A
+-commutativeN/A
lower-fma.f64N/A
lower-log.f64N/A
lower-fma.f6499.0
Applied rewrites99.0%
Final simplification98.3%
(FPCore (x y z) :precision binary64 (if (<= (+ (log z) (- 1.0 z)) -150.0) (fma (- z) y (* 0.5 x)) (fma y (log z) y)))
double code(double x, double y, double z) {
double tmp;
if ((log(z) + (1.0 - z)) <= -150.0) {
tmp = fma(-z, y, (0.5 * x));
} else {
tmp = fma(y, log(z), y);
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (Float64(log(z) + Float64(1.0 - z)) <= -150.0) tmp = fma(Float64(-z), y, Float64(0.5 * x)); else tmp = fma(y, log(z), y); end return tmp end
code[x_, y_, z_] := If[LessEqual[N[(N[Log[z], $MachinePrecision] + N[(1.0 - z), $MachinePrecision]), $MachinePrecision], -150.0], N[((-z) * y + N[(0.5 * x), $MachinePrecision]), $MachinePrecision], N[(y * N[Log[z], $MachinePrecision] + y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\log z + \left(1 - z\right) \leq -150:\\
\;\;\;\;\mathsf{fma}\left(-z, y, 0.5 \cdot x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y, \log z, y\right)\\
\end{array}
\end{array}
if (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z)) < -150Initial program 99.9%
lift--.f64N/A
lift-log.f64N/A
flip-+N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
clear-numN/A
flip-+N/A
lift-+.f64N/A
lower-/.f6499.7
Applied rewrites99.7%
Taylor expanded in z around inf
lower-/.f6481.2
Applied rewrites81.2%
lift-*.f64N/A
lift-/.f64N/A
lift-/.f64N/A
+-commutativeN/A
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lift-/.f64N/A
frac-2negN/A
metadata-evalN/A
remove-double-divN/A
lower-fma.f64N/A
lower-neg.f6481.4
Applied rewrites81.4%
if -150 < (+.f64 (-.f64 #s(literal 1 binary64) z) (log.f64 z)) Initial program 99.7%
Taylor expanded in z around 0
distribute-lft-inN/A
*-rgt-identityN/A
associate-+r+N/A
+-commutativeN/A
lower-fma.f64N/A
lower-log.f64N/A
lower-fma.f6496.3
Applied rewrites96.3%
Taylor expanded in y around inf
+-commutativeN/A
distribute-lft-inN/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-log.f6465.0
Applied rewrites65.0%
Final simplification79.8%
(FPCore (x y z)
:precision binary64
(let* ((t_0 (fma y (- (log z) z) y)))
(if (<= y -3.5e+87)
t_0
(if (<= y 520000000000.0) (fma (- z) y (* 0.5 x)) t_0))))
double code(double x, double y, double z) {
double t_0 = fma(y, (log(z) - z), y);
double tmp;
if (y <= -3.5e+87) {
tmp = t_0;
} else if (y <= 520000000000.0) {
tmp = fma(-z, y, (0.5 * x));
} else {
tmp = t_0;
}
return tmp;
}
function code(x, y, z) t_0 = fma(y, Float64(log(z) - z), y) tmp = 0.0 if (y <= -3.5e+87) tmp = t_0; elseif (y <= 520000000000.0) tmp = fma(Float64(-z), y, Float64(0.5 * x)); else tmp = t_0; end return tmp end
code[x_, y_, z_] := Block[{t$95$0 = N[(y * N[(N[Log[z], $MachinePrecision] - z), $MachinePrecision] + y), $MachinePrecision]}, If[LessEqual[y, -3.5e+87], t$95$0, If[LessEqual[y, 520000000000.0], N[((-z) * y + N[(0.5 * x), $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(y, \log z - z, y\right)\\
\mathbf{if}\;y \leq -3.5 \cdot 10^{+87}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;y \leq 520000000000:\\
\;\;\;\;\mathsf{fma}\left(-z, y, 0.5 \cdot x\right)\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if y < -3.49999999999999986e87 or 5.2e11 < y Initial program 99.8%
Taylor expanded in x around 0
sub-negN/A
associate-+r+N/A
mul-1-negN/A
+-commutativeN/A
distribute-lft-inN/A
*-rgt-identityN/A
lower-fma.f64N/A
mul-1-negN/A
sub-negN/A
lower--.f64N/A
lower-log.f6487.3
Applied rewrites87.3%
if -3.49999999999999986e87 < y < 5.2e11Initial program 99.9%
lift--.f64N/A
lift-log.f64N/A
flip-+N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
clear-numN/A
flip-+N/A
lift-+.f64N/A
lower-/.f6499.8
Applied rewrites99.8%
Taylor expanded in z around inf
lower-/.f6489.2
Applied rewrites89.2%
lift-*.f64N/A
lift-/.f64N/A
lift-/.f64N/A
+-commutativeN/A
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lift-/.f64N/A
frac-2negN/A
metadata-evalN/A
remove-double-divN/A
lower-fma.f64N/A
lower-neg.f6489.4
Applied rewrites89.4%
Final simplification88.5%
(FPCore (x y z) :precision binary64 (fma (- z) y (* 0.5 x)))
double code(double x, double y, double z) {
return fma(-z, y, (0.5 * x));
}
function code(x, y, z) return fma(Float64(-z), y, Float64(0.5 * x)) end
code[x_, y_, z_] := N[((-z) * y + N[(0.5 * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-z, y, 0.5 \cdot x\right)
\end{array}
Initial program 99.9%
lift--.f64N/A
lift-log.f64N/A
flip-+N/A
clear-numN/A
un-div-invN/A
lower-/.f64N/A
clear-numN/A
flip-+N/A
lift-+.f64N/A
lower-/.f6499.7
Applied rewrites99.7%
Taylor expanded in z around inf
lower-/.f6476.8
Applied rewrites76.8%
lift-*.f64N/A
lift-/.f64N/A
lift-/.f64N/A
+-commutativeN/A
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
lift-/.f64N/A
frac-2negN/A
metadata-evalN/A
remove-double-divN/A
lower-fma.f64N/A
lower-neg.f6476.9
Applied rewrites76.9%
Final simplification76.9%
(FPCore (x y z) :precision binary64 (* 0.5 x))
double code(double x, double y, double z) {
return 0.5 * x;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = 0.5d0 * x
end function
public static double code(double x, double y, double z) {
return 0.5 * x;
}
def code(x, y, z): return 0.5 * x
function code(x, y, z) return Float64(0.5 * x) end
function tmp = code(x, y, z) tmp = 0.5 * x; end
code[x_, y_, z_] := N[(0.5 * x), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot x
\end{array}
Initial program 99.9%
Taylor expanded in x around inf
lower-*.f6438.7
Applied rewrites38.7%
(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 2024219
(FPCore (x y z)
:name "System.Random.MWC.Distributions:gamma from mwc-random-0.13.3.2"
:precision binary64
:alt
(! :herbie-platform default (- (+ y (* 1/2 x)) (* y (- z (log z)))))
(+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))