
(FPCore (x y z) :precision binary64 (- (+ (- x (* (+ y 0.5) (log y))) y) z))
double code(double x, double y, double z) {
return ((x - ((y + 0.5) * log(y))) + 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 - ((y + 0.5d0) * log(y))) + y) - z
end function
public static double code(double x, double y, double z) {
return ((x - ((y + 0.5) * Math.log(y))) + y) - z;
}
def code(x, y, z): return ((x - ((y + 0.5) * math.log(y))) + y) - z
function code(x, y, z) return Float64(Float64(Float64(x - Float64(Float64(y + 0.5) * log(y))) + y) - z) end
function tmp = code(x, y, z) tmp = ((x - ((y + 0.5) * log(y))) + y) - z; end
code[x_, y_, z_] := N[(N[(N[(x - N[(N[(y + 0.5), $MachinePrecision] * N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(x - \left(y + 0.5\right) \cdot \log y\right) + y\right) - z
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z) :precision binary64 (- (+ (- x (* (+ y 0.5) (log y))) y) z))
double code(double x, double y, double z) {
return ((x - ((y + 0.5) * log(y))) + 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 - ((y + 0.5d0) * log(y))) + y) - z
end function
public static double code(double x, double y, double z) {
return ((x - ((y + 0.5) * Math.log(y))) + y) - z;
}
def code(x, y, z): return ((x - ((y + 0.5) * math.log(y))) + y) - z
function code(x, y, z) return Float64(Float64(Float64(x - Float64(Float64(y + 0.5) * log(y))) + y) - z) end
function tmp = code(x, y, z) tmp = ((x - ((y + 0.5) * log(y))) + y) - z; end
code[x_, y_, z_] := N[(N[(N[(x - N[(N[(y + 0.5), $MachinePrecision] * N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(x - \left(y + 0.5\right) \cdot \log y\right) + y\right) - z
\end{array}
(FPCore (x y z) :precision binary64 (fma (- -0.5 y) (log y) (+ (- y z) x)))
double code(double x, double y, double z) {
return fma((-0.5 - y), log(y), ((y - z) + x));
}
function code(x, y, z) return fma(Float64(-0.5 - y), log(y), Float64(Float64(y - z) + x)) end
code[x_, y_, z_] := N[(N[(-0.5 - y), $MachinePrecision] * N[Log[y], $MachinePrecision] + N[(N[(y - z), $MachinePrecision] + x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-0.5 - y, \log y, \left(y - z\right) + x\right)
\end{array}
Initial program 99.8%
lift--.f64N/A
lift-+.f64N/A
associate--l+N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
associate-+l+N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
lift-+.f64N/A
+-commutativeN/A
distribute-neg-inN/A
unsub-negN/A
lower--.f64N/A
metadata-evalN/A
lower-+.f64N/A
lower--.f6499.9
Applied rewrites99.9%
Final simplification99.9%
(FPCore (x y z) :precision binary64 (if (<= y 5.2e-5) (- (fma -0.5 (log y) x) z) (- (+ (- x (* (log y) y)) y) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= 5.2e-5) {
tmp = fma(-0.5, log(y), x) - z;
} else {
tmp = ((x - (log(y) * y)) + y) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= 5.2e-5) tmp = Float64(fma(-0.5, log(y), x) - z); else tmp = Float64(Float64(Float64(x - Float64(log(y) * y)) + y) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, 5.2e-5], N[(N[(-0.5 * N[Log[y], $MachinePrecision] + x), $MachinePrecision] - z), $MachinePrecision], N[(N[(N[(x - N[(N[Log[y], $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 5.2 \cdot 10^{-5}:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log y, x\right) - z\\
\mathbf{else}:\\
\;\;\;\;\left(\left(x - \log y \cdot y\right) + y\right) - z\\
\end{array}
\end{array}
if y < 5.19999999999999968e-5Initial program 100.0%
Taylor expanded in y around 0
+-commutativeN/A
associate--r+N/A
lower--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-log.f6499.6
Applied rewrites99.6%
if 5.19999999999999968e-5 < y Initial program 99.7%
Taylor expanded in y around inf
*-commutativeN/A
associate-*r*N/A
mul-1-negN/A
log-recN/A
remove-double-negN/A
lower-*.f64N/A
lower-log.f6498.5
Applied rewrites98.5%
(FPCore (x y z) :precision binary64 (if (<= y 52.0) (- (fma -0.5 (log y) x) z) (- (fma (- -0.5 y) (log y) y) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= 52.0) {
tmp = fma(-0.5, log(y), x) - z;
} else {
tmp = fma((-0.5 - y), log(y), y) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= 52.0) tmp = Float64(fma(-0.5, log(y), x) - z); else tmp = Float64(fma(Float64(-0.5 - y), log(y), y) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, 52.0], N[(N[(-0.5 * N[Log[y], $MachinePrecision] + x), $MachinePrecision] - z), $MachinePrecision], N[(N[(N[(-0.5 - y), $MachinePrecision] * N[Log[y], $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 52:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log y, x\right) - z\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-0.5 - y, \log y, y\right) - z\\
\end{array}
\end{array}
if y < 52Initial program 100.0%
Taylor expanded in y around 0
+-commutativeN/A
associate--r+N/A
lower--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-log.f6499.6
Applied rewrites99.6%
if 52 < y Initial program 99.7%
Taylor expanded in x around 0
sub-negN/A
+-commutativeN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-neg-inN/A
metadata-evalN/A
unsub-negN/A
lower--.f64N/A
lower-log.f6483.3
Applied rewrites83.3%
(FPCore (x y z) :precision binary64 (if (<= y 52.0) (- (fma -0.5 (log y) x) z) (- y (fma (+ 0.5 y) (log y) z))))
double code(double x, double y, double z) {
double tmp;
if (y <= 52.0) {
tmp = fma(-0.5, log(y), x) - z;
} else {
tmp = y - fma((0.5 + y), log(y), z);
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= 52.0) tmp = Float64(fma(-0.5, log(y), x) - z); else tmp = Float64(y - fma(Float64(0.5 + y), log(y), z)); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, 52.0], N[(N[(-0.5 * N[Log[y], $MachinePrecision] + x), $MachinePrecision] - z), $MachinePrecision], N[(y - N[(N[(0.5 + y), $MachinePrecision] * N[Log[y], $MachinePrecision] + z), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 52:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log y, x\right) - z\\
\mathbf{else}:\\
\;\;\;\;y - \mathsf{fma}\left(0.5 + y, \log y, z\right)\\
\end{array}
\end{array}
if y < 52Initial program 100.0%
Taylor expanded in y around 0
+-commutativeN/A
associate--r+N/A
lower--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-log.f6499.6
Applied rewrites99.6%
if 52 < y Initial program 99.7%
Taylor expanded in x around 0
lower--.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-+.f64N/A
lower-log.f6483.2
Applied rewrites83.2%
(FPCore (x y z) :precision binary64 (if (<= y 3e+27) (- (fma -0.5 (log y) x) z) (- (fma (- y) (log y) y) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= 3e+27) {
tmp = fma(-0.5, log(y), x) - z;
} else {
tmp = fma(-y, log(y), y) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= 3e+27) tmp = Float64(fma(-0.5, log(y), x) - z); else tmp = Float64(fma(Float64(-y), log(y), y) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, 3e+27], N[(N[(-0.5 * N[Log[y], $MachinePrecision] + x), $MachinePrecision] - z), $MachinePrecision], N[(N[((-y) * N[Log[y], $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 3 \cdot 10^{+27}:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log y, x\right) - z\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-y, \log y, y\right) - z\\
\end{array}
\end{array}
if y < 2.99999999999999976e27Initial program 100.0%
Taylor expanded in y around 0
+-commutativeN/A
associate--r+N/A
lower--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-log.f6496.7
Applied rewrites96.7%
if 2.99999999999999976e27 < y Initial program 99.7%
Taylor expanded in x around 0
sub-negN/A
+-commutativeN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
distribute-neg-inN/A
metadata-evalN/A
unsub-negN/A
lower--.f64N/A
lower-log.f6485.2
Applied rewrites85.2%
Taylor expanded in y around inf
Applied rewrites85.2%
(FPCore (x y z) :precision binary64 (if (<= y 1.85e+90) (- (fma -0.5 (log y) x) z) (* (- 1.0 (log y)) y)))
double code(double x, double y, double z) {
double tmp;
if (y <= 1.85e+90) {
tmp = fma(-0.5, log(y), x) - z;
} else {
tmp = (1.0 - log(y)) * y;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= 1.85e+90) tmp = Float64(fma(-0.5, log(y), x) - z); else tmp = Float64(Float64(1.0 - log(y)) * y); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, 1.85e+90], N[(N[(-0.5 * N[Log[y], $MachinePrecision] + x), $MachinePrecision] - z), $MachinePrecision], N[(N[(1.0 - N[Log[y], $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 1.85 \cdot 10^{+90}:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log y, x\right) - z\\
\mathbf{else}:\\
\;\;\;\;\left(1 - \log y\right) \cdot y\\
\end{array}
\end{array}
if y < 1.85e90Initial program 99.9%
Taylor expanded in y around 0
+-commutativeN/A
associate--r+N/A
lower--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-log.f6493.3
Applied rewrites93.3%
if 1.85e90 < y Initial program 99.7%
Taylor expanded in y around inf
*-commutativeN/A
mul-1-negN/A
log-recN/A
remove-double-negN/A
lower-*.f64N/A
lower--.f64N/A
lower-log.f6472.2
Applied rewrites72.2%
(FPCore (x y z) :precision binary64 (if (<= y 1.85e+86) (- (+ (/ 1.0 (/ 1.0 x)) y) z) (* (- 1.0 (log y)) y)))
double code(double x, double y, double z) {
double tmp;
if (y <= 1.85e+86) {
tmp = ((1.0 / (1.0 / x)) + y) - z;
} else {
tmp = (1.0 - log(y)) * 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 (y <= 1.85d+86) then
tmp = ((1.0d0 / (1.0d0 / x)) + y) - z
else
tmp = (1.0d0 - log(y)) * y
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= 1.85e+86) {
tmp = ((1.0 / (1.0 / x)) + y) - z;
} else {
tmp = (1.0 - Math.log(y)) * y;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= 1.85e+86: tmp = ((1.0 / (1.0 / x)) + y) - z else: tmp = (1.0 - math.log(y)) * y return tmp
function code(x, y, z) tmp = 0.0 if (y <= 1.85e+86) tmp = Float64(Float64(Float64(1.0 / Float64(1.0 / x)) + y) - z); else tmp = Float64(Float64(1.0 - log(y)) * y); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= 1.85e+86) tmp = ((1.0 / (1.0 / x)) + y) - z; else tmp = (1.0 - log(y)) * y; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, 1.85e+86], N[(N[(N[(1.0 / N[(1.0 / x), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision], N[(N[(1.0 - N[Log[y], $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 1.85 \cdot 10^{+86}:\\
\;\;\;\;\left(\frac{1}{\frac{1}{x}} + y\right) - z\\
\mathbf{else}:\\
\;\;\;\;\left(1 - \log y\right) \cdot y\\
\end{array}
\end{array}
if y < 1.84999999999999996e86Initial program 99.9%
lift--.f64N/A
flip--N/A
clear-numN/A
lower-/.f64N/A
clear-numN/A
flip--N/A
lift--.f64N/A
lower-/.f6499.8
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
Applied rewrites99.8%
Taylor expanded in x around inf
lower-/.f6477.6
Applied rewrites77.6%
if 1.84999999999999996e86 < y Initial program 99.7%
Taylor expanded in y around inf
*-commutativeN/A
mul-1-negN/A
log-recN/A
remove-double-negN/A
lower-*.f64N/A
lower--.f64N/A
lower-log.f6472.2
Applied rewrites72.2%
(FPCore (x y z) :precision binary64 (let* ((t_0 (/ 1.0 (/ 1.0 x)))) (if (<= x -5.8e+19) t_0 (if (<= x 3.1e+41) (- z) t_0))))
double code(double x, double y, double z) {
double t_0 = 1.0 / (1.0 / x);
double tmp;
if (x <= -5.8e+19) {
tmp = t_0;
} else if (x <= 3.1e+41) {
tmp = -z;
} else {
tmp = t_0;
}
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) :: tmp
t_0 = 1.0d0 / (1.0d0 / x)
if (x <= (-5.8d+19)) then
tmp = t_0
else if (x <= 3.1d+41) then
tmp = -z
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double t_0 = 1.0 / (1.0 / x);
double tmp;
if (x <= -5.8e+19) {
tmp = t_0;
} else if (x <= 3.1e+41) {
tmp = -z;
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y, z): t_0 = 1.0 / (1.0 / x) tmp = 0 if x <= -5.8e+19: tmp = t_0 elif x <= 3.1e+41: tmp = -z else: tmp = t_0 return tmp
function code(x, y, z) t_0 = Float64(1.0 / Float64(1.0 / x)) tmp = 0.0 if (x <= -5.8e+19) tmp = t_0; elseif (x <= 3.1e+41) tmp = Float64(-z); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y, z) t_0 = 1.0 / (1.0 / x); tmp = 0.0; if (x <= -5.8e+19) tmp = t_0; elseif (x <= 3.1e+41) tmp = -z; else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_, z_] := Block[{t$95$0 = N[(1.0 / N[(1.0 / x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -5.8e+19], t$95$0, If[LessEqual[x, 3.1e+41], (-z), t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{\frac{1}{x}}\\
\mathbf{if}\;x \leq -5.8 \cdot 10^{+19}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;x \leq 3.1 \cdot 10^{+41}:\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if x < -5.8e19 or 3.1e41 < x Initial program 99.9%
lift--.f64N/A
flip--N/A
clear-numN/A
lower-/.f64N/A
clear-numN/A
flip--N/A
lift--.f64N/A
lower-/.f6499.7
lift--.f64N/A
lift-+.f64N/A
Applied rewrites99.7%
Taylor expanded in x around inf
lower-/.f6464.7
Applied rewrites64.7%
if -5.8e19 < x < 3.1e41Initial program 99.8%
Taylor expanded in z around inf
mul-1-negN/A
lower-neg.f6440.5
Applied rewrites40.5%
(FPCore (x y z) :precision binary64 (- (+ (/ 1.0 (/ 1.0 x)) y) z))
double code(double x, double y, double z) {
return ((1.0 / (1.0 / x)) + 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 = ((1.0d0 / (1.0d0 / x)) + y) - z
end function
public static double code(double x, double y, double z) {
return ((1.0 / (1.0 / x)) + y) - z;
}
def code(x, y, z): return ((1.0 / (1.0 / x)) + y) - z
function code(x, y, z) return Float64(Float64(Float64(1.0 / Float64(1.0 / x)) + y) - z) end
function tmp = code(x, y, z) tmp = ((1.0 / (1.0 / x)) + y) - z; end
code[x_, y_, z_] := N[(N[(N[(1.0 / N[(1.0 / x), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{\frac{1}{x}} + y\right) - z
\end{array}
Initial program 99.8%
lift--.f64N/A
flip--N/A
clear-numN/A
lower-/.f64N/A
clear-numN/A
flip--N/A
lift--.f64N/A
lower-/.f6499.7
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
Applied rewrites99.7%
Taylor expanded in x around inf
lower-/.f6459.5
Applied rewrites59.5%
(FPCore (x y z) :precision binary64 (- z))
double code(double x, double y, double z) {
return -z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = -z
end function
public static double code(double x, double y, double z) {
return -z;
}
def code(x, y, z): return -z
function code(x, y, z) return Float64(-z) end
function tmp = code(x, y, z) tmp = -z; end
code[x_, y_, z_] := (-z)
\begin{array}{l}
\\
-z
\end{array}
Initial program 99.8%
Taylor expanded in z around inf
mul-1-negN/A
lower-neg.f6429.8
Applied rewrites29.8%
(FPCore (x y z) :precision binary64 (- (- (+ y x) z) (* (+ y 0.5) (log y))))
double code(double x, double y, double z) {
return ((y + x) - z) - ((y + 0.5) * log(y));
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = ((y + x) - z) - ((y + 0.5d0) * log(y))
end function
public static double code(double x, double y, double z) {
return ((y + x) - z) - ((y + 0.5) * Math.log(y));
}
def code(x, y, z): return ((y + x) - z) - ((y + 0.5) * math.log(y))
function code(x, y, z) return Float64(Float64(Float64(y + x) - z) - Float64(Float64(y + 0.5) * log(y))) end
function tmp = code(x, y, z) tmp = ((y + x) - z) - ((y + 0.5) * log(y)); end
code[x_, y_, z_] := N[(N[(N[(y + x), $MachinePrecision] - z), $MachinePrecision] - N[(N[(y + 0.5), $MachinePrecision] * N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(y + x\right) - z\right) - \left(y + 0.5\right) \cdot \log y
\end{array}
herbie shell --seed 2024332
(FPCore (x y z)
:name "Numeric.SpecFunctions:stirlingError from math-functions-0.1.5.2"
:precision binary64
:alt
(! :herbie-platform default (- (- (+ y x) z) (* (+ y 1/2) (log y))))
(- (+ (- x (* (+ y 0.5) (log y))) y) z))