
(FPCore (x y) :precision binary64 (/ (exp (* x (log (/ x (+ x y))))) x))
double code(double x, double y) {
return exp((x * log((x / (x + y))))) / x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = exp((x * log((x / (x + y))))) / x
end function
public static double code(double x, double y) {
return Math.exp((x * Math.log((x / (x + y))))) / x;
}
def code(x, y): return math.exp((x * math.log((x / (x + y))))) / x
function code(x, y) return Float64(exp(Float64(x * log(Float64(x / Float64(x + y))))) / x) end
function tmp = code(x, y) tmp = exp((x * log((x / (x + y))))) / x; end
code[x_, y_] := N[(N[Exp[N[(x * N[Log[N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{e^{x \cdot \log \left(\frac{x}{x + y}\right)}}{x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (/ (exp (* x (log (/ x (+ x y))))) x))
double code(double x, double y) {
return exp((x * log((x / (x + y))))) / x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = exp((x * log((x / (x + y))))) / x
end function
public static double code(double x, double y) {
return Math.exp((x * Math.log((x / (x + y))))) / x;
}
def code(x, y): return math.exp((x * math.log((x / (x + y))))) / x
function code(x, y) return Float64(exp(Float64(x * log(Float64(x / Float64(x + y))))) / x) end
function tmp = code(x, y) tmp = exp((x * log((x / (x + y))))) / x; end
code[x_, y_] := N[(N[Exp[N[(x * N[Log[N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{e^{x \cdot \log \left(\frac{x}{x + y}\right)}}{x}
\end{array}
(FPCore (x y) :precision binary64 (if (or (<= x -16.5) (not (<= x 1.3))) (/ (exp (- y)) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if ((x <= -16.5) || !(x <= 1.3)) {
tmp = exp(-y) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-16.5d0)) .or. (.not. (x <= 1.3d0))) then
tmp = exp(-y) / x
else
tmp = 1.0d0 / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -16.5) || !(x <= 1.3)) {
tmp = Math.exp(-y) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -16.5) or not (x <= 1.3): tmp = math.exp(-y) / x else: tmp = 1.0 / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -16.5) || !(x <= 1.3)) tmp = Float64(exp(Float64(-y)) / x); else tmp = Float64(1.0 / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -16.5) || ~((x <= 1.3))) tmp = exp(-y) / x; else tmp = 1.0 / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -16.5], N[Not[LessEqual[x, 1.3]], $MachinePrecision]], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -16.5 \lor \neg \left(x \leq 1.3\right):\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -16.5 or 1.30000000000000004 < x Initial program 72.6%
Taylor expanded in x around inf
mul-1-negN/A
lower-neg.f64100.0
Applied rewrites100.0%
if -16.5 < x < 1.30000000000000004Initial program 84.9%
Taylor expanded in x around 0
Applied rewrites98.6%
Final simplification99.5%
(FPCore (x y)
:precision binary64
(if (<= y -22.0)
(/
(fma
(-
(*
(*
(/ (- (* (- (* -0.16666666666666666 x) 0.5) x) 0.3333333333333333) x)
(/ y x))
y)
1.0)
y
1.0)
x)
(/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (y <= -22.0) {
tmp = fma(((((((((-0.16666666666666666 * x) - 0.5) * x) - 0.3333333333333333) / x) * (y / x)) * y) - 1.0), y, 1.0) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (y <= -22.0) tmp = Float64(fma(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(-0.16666666666666666 * x) - 0.5) * x) - 0.3333333333333333) / x) * Float64(y / x)) * y) - 1.0), y, 1.0) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[y, -22.0], N[(N[(N[(N[(N[(N[(N[(N[(N[(N[(-0.16666666666666666 * x), $MachinePrecision] - 0.5), $MachinePrecision] * x), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] / x), $MachinePrecision] * N[(y / x), $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision] - 1.0), $MachinePrecision] * y + 1.0), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -22:\\
\;\;\;\;\frac{\mathsf{fma}\left(\left(\frac{\left(-0.16666666666666666 \cdot x - 0.5\right) \cdot x - 0.3333333333333333}{x} \cdot \frac{y}{x}\right) \cdot y - 1, y, 1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if y < -22Initial program 39.2%
Taylor expanded in y around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites51.1%
Taylor expanded in x around 0
Applied rewrites18.0%
Taylor expanded in y around inf
Applied rewrites66.9%
if -22 < y Initial program 84.5%
Taylor expanded in x around 0
Applied rewrites81.1%
(FPCore (x y) :precision binary64 (if (<= y -8e+64) (/ (/ (* (* (fma 0.5 x 0.5) y) y) x) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (y <= -8e+64) {
tmp = (((fma(0.5, x, 0.5) * y) * y) / x) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (y <= -8e+64) tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 0.5) * y) * y) / x) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[y, -8e+64], N[(N[(N[(N[(N[(0.5 * x + 0.5), $MachinePrecision] * y), $MachinePrecision] * y), $MachinePrecision] / x), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -8 \cdot 10^{+64}:\\
\;\;\;\;\frac{\frac{\left(\mathsf{fma}\left(0.5, x, 0.5\right) \cdot y\right) \cdot y}{x}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if y < -8.00000000000000017e64Initial program 45.5%
Taylor expanded in y around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower--.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
lower-+.f64N/A
associate-*r/N/A
metadata-evalN/A
lower-/.f6457.4
Applied rewrites57.4%
Taylor expanded in x around 0
Applied rewrites44.1%
Taylor expanded in y around inf
Applied rewrites78.5%
if -8.00000000000000017e64 < y Initial program 81.4%
Taylor expanded in x around 0
Applied rewrites77.7%
(FPCore (x y) :precision binary64 (if (<= y -1.3e+111) (/ (fma (* -0.16666666666666666 (* y y)) y 1.0) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (y <= -1.3e+111) {
tmp = fma((-0.16666666666666666 * (y * y)), y, 1.0) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (y <= -1.3e+111) tmp = Float64(fma(Float64(-0.16666666666666666 * Float64(y * y)), y, 1.0) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[y, -1.3e+111], N[(N[(N[(-0.16666666666666666 * N[(y * y), $MachinePrecision]), $MachinePrecision] * y + 1.0), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.3 \cdot 10^{+111}:\\
\;\;\;\;\frac{\mathsf{fma}\left(-0.16666666666666666 \cdot \left(y \cdot y\right), y, 1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if y < -1.2999999999999999e111Initial program 55.4%
Taylor expanded in y around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites82.0%
Taylor expanded in x around inf
Applied rewrites82.0%
Taylor expanded in y around inf
Applied rewrites82.0%
Taylor expanded in x around inf
Applied rewrites82.0%
if -1.2999999999999999e111 < y Initial program 79.4%
Taylor expanded in x around 0
Applied rewrites76.2%
(FPCore (x y) :precision binary64 (if (<= y -1e+113) (/ (fma (- (* 0.5 y) 1.0) y 1.0) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (y <= -1e+113) {
tmp = fma(((0.5 * y) - 1.0), y, 1.0) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (y <= -1e+113) tmp = Float64(fma(Float64(Float64(0.5 * y) - 1.0), y, 1.0) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[y, -1e+113], N[(N[(N[(N[(0.5 * y), $MachinePrecision] - 1.0), $MachinePrecision] * y + 1.0), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1 \cdot 10^{+113}:\\
\;\;\;\;\frac{\mathsf{fma}\left(0.5 \cdot y - 1, y, 1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if y < -1e113Initial program 55.4%
Taylor expanded in y around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower--.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
lower-+.f64N/A
associate-*r/N/A
metadata-evalN/A
lower-/.f6470.1
Applied rewrites70.1%
Taylor expanded in x around inf
Applied rewrites71.2%
if -1e113 < y Initial program 79.4%
Taylor expanded in x around 0
Applied rewrites76.2%
(FPCore (x y) :precision binary64 (/ 1.0 x))
double code(double x, double y) {
return 1.0 / x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 / x
end function
public static double code(double x, double y) {
return 1.0 / x;
}
def code(x, y): return 1.0 / x
function code(x, y) return Float64(1.0 / x) end
function tmp = code(x, y) tmp = 1.0 / x; end
code[x_, y_] := N[(1.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x}
\end{array}
Initial program 76.9%
Taylor expanded in x around 0
Applied rewrites70.4%
(FPCore (x y)
:precision binary64
(let* ((t_0 (/ (exp (/ -1.0 y)) x)) (t_1 (/ (pow (/ x (+ y x)) x) x)))
(if (< y -3.7311844206647956e+94)
t_0
(if (< y 2.817959242728288e+37)
t_1
(if (< y 2.347387415166998e+178) (log (exp t_1)) t_0)))))
double code(double x, double y) {
double t_0 = exp((-1.0 / y)) / x;
double t_1 = pow((x / (y + x)), x) / x;
double tmp;
if (y < -3.7311844206647956e+94) {
tmp = t_0;
} else if (y < 2.817959242728288e+37) {
tmp = t_1;
} else if (y < 2.347387415166998e+178) {
tmp = log(exp(t_1));
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: t_1
real(8) :: tmp
t_0 = exp(((-1.0d0) / y)) / x
t_1 = ((x / (y + x)) ** x) / x
if (y < (-3.7311844206647956d+94)) then
tmp = t_0
else if (y < 2.817959242728288d+37) then
tmp = t_1
else if (y < 2.347387415166998d+178) then
tmp = log(exp(t_1))
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = Math.exp((-1.0 / y)) / x;
double t_1 = Math.pow((x / (y + x)), x) / x;
double tmp;
if (y < -3.7311844206647956e+94) {
tmp = t_0;
} else if (y < 2.817959242728288e+37) {
tmp = t_1;
} else if (y < 2.347387415166998e+178) {
tmp = Math.log(Math.exp(t_1));
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = math.exp((-1.0 / y)) / x t_1 = math.pow((x / (y + x)), x) / x tmp = 0 if y < -3.7311844206647956e+94: tmp = t_0 elif y < 2.817959242728288e+37: tmp = t_1 elif y < 2.347387415166998e+178: tmp = math.log(math.exp(t_1)) else: tmp = t_0 return tmp
function code(x, y) t_0 = Float64(exp(Float64(-1.0 / y)) / x) t_1 = Float64((Float64(x / Float64(y + x)) ^ x) / x) tmp = 0.0 if (y < -3.7311844206647956e+94) tmp = t_0; elseif (y < 2.817959242728288e+37) tmp = t_1; elseif (y < 2.347387415166998e+178) tmp = log(exp(t_1)); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y) t_0 = exp((-1.0 / y)) / x; t_1 = ((x / (y + x)) ^ x) / x; tmp = 0.0; if (y < -3.7311844206647956e+94) tmp = t_0; elseif (y < 2.817959242728288e+37) tmp = t_1; elseif (y < 2.347387415166998e+178) tmp = log(exp(t_1)); else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(N[Exp[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]}, Block[{t$95$1 = N[(N[Power[N[(x / N[(y + x), $MachinePrecision]), $MachinePrecision], x], $MachinePrecision] / x), $MachinePrecision]}, If[Less[y, -3.7311844206647956e+94], t$95$0, If[Less[y, 2.817959242728288e+37], t$95$1, If[Less[y, 2.347387415166998e+178], N[Log[N[Exp[t$95$1], $MachinePrecision]], $MachinePrecision], t$95$0]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{e^{\frac{-1}{y}}}{x}\\
t_1 := \frac{{\left(\frac{x}{y + x}\right)}^{x}}{x}\\
\mathbf{if}\;y < -3.7311844206647956 \cdot 10^{+94}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;y < 2.817959242728288 \cdot 10^{+37}:\\
\;\;\;\;t\_1\\
\mathbf{elif}\;y < 2.347387415166998 \cdot 10^{+178}:\\
\;\;\;\;\log \left(e^{t\_1}\right)\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
herbie shell --seed 2024329
(FPCore (x y)
:name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, F"
:precision binary64
:alt
(! :herbie-platform default (if (< y -37311844206647956000000000000000000000000000000000000000000000000000000000000000000000000000000) (/ (exp (/ -1 y)) x) (if (< y 28179592427282880000000000000000000000) (/ (pow (/ x (+ y x)) x) x) (if (< y 23473874151669980000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000) (log (exp (/ (pow (/ x (+ y x)) x) x))) (/ (exp (/ -1 y)) x)))))
(/ (exp (* x (log (/ x (+ x y))))) x))