
(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 11 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 (<= x -1550.0) (/ 1.0 (* (exp (- (- y))) x)) (if (<= x 1.25e-35) (/ 1.0 x) (/ (exp (- y)) x))))
double code(double x, double y) {
double tmp;
if (x <= -1550.0) {
tmp = 1.0 / (exp(-(-y)) * x);
} else if (x <= 1.25e-35) {
tmp = 1.0 / x;
} else {
tmp = exp(-y) / x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-1550.0d0)) then
tmp = 1.0d0 / (exp(-(-y)) * x)
else if (x <= 1.25d-35) then
tmp = 1.0d0 / x
else
tmp = exp(-y) / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -1550.0) {
tmp = 1.0 / (Math.exp(-(-y)) * x);
} else if (x <= 1.25e-35) {
tmp = 1.0 / x;
} else {
tmp = Math.exp(-y) / x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1550.0: tmp = 1.0 / (math.exp(-(-y)) * x) elif x <= 1.25e-35: tmp = 1.0 / x else: tmp = math.exp(-y) / x return tmp
function code(x, y) tmp = 0.0 if (x <= -1550.0) tmp = Float64(1.0 / Float64(exp(Float64(-Float64(-y))) * x)); elseif (x <= 1.25e-35) tmp = Float64(1.0 / x); else tmp = Float64(exp(Float64(-y)) / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1550.0) tmp = 1.0 / (exp(-(-y)) * x); elseif (x <= 1.25e-35) tmp = 1.0 / x; else tmp = exp(-y) / x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1550.0], N[(1.0 / N[(N[Exp[(-(-y))], $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 1.25e-35], N[(1.0 / x), $MachinePrecision], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1550:\\
\;\;\;\;\frac{1}{e^{-\left(-y\right)} \cdot x}\\
\mathbf{elif}\;x \leq 1.25 \cdot 10^{-35}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{e^{-y}}{x}\\
\end{array}
\end{array}
if x < -1550Initial program 76.7%
Taylor expanded in x around inf
mul-1-negN/A
lower-neg.f64100.0
Applied rewrites100.0%
lift-/.f64N/A
clear-numN/A
lower-/.f64N/A
div-invN/A
lower-*.f64N/A
lift-exp.f64N/A
rec-expN/A
lower-exp.f64N/A
lower-neg.f64100.0
Applied rewrites100.0%
if -1550 < x < 1.24999999999999991e-35Initial program 83.1%
Taylor expanded in x around 0
Applied rewrites97.2%
if 1.24999999999999991e-35 < x Initial program 80.9%
Taylor expanded in x around inf
mul-1-negN/A
lower-neg.f64100.0
Applied rewrites100.0%
Final simplification98.8%
(FPCore (x y) :precision binary64 (let* ((t_0 (/ (exp (- y)) x))) (if (<= x -1550.0) t_0 (if (<= x 1.25e-35) (/ 1.0 x) t_0))))
double code(double x, double y) {
double t_0 = exp(-y) / x;
double tmp;
if (x <= -1550.0) {
tmp = t_0;
} else if (x <= 1.25e-35) {
tmp = 1.0 / x;
} 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) :: tmp
t_0 = exp(-y) / x
if (x <= (-1550.0d0)) then
tmp = t_0
else if (x <= 1.25d-35) then
tmp = 1.0d0 / x
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = Math.exp(-y) / x;
double tmp;
if (x <= -1550.0) {
tmp = t_0;
} else if (x <= 1.25e-35) {
tmp = 1.0 / x;
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = math.exp(-y) / x tmp = 0 if x <= -1550.0: tmp = t_0 elif x <= 1.25e-35: tmp = 1.0 / x else: tmp = t_0 return tmp
function code(x, y) t_0 = Float64(exp(Float64(-y)) / x) tmp = 0.0 if (x <= -1550.0) tmp = t_0; elseif (x <= 1.25e-35) tmp = Float64(1.0 / x); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y) t_0 = exp(-y) / x; tmp = 0.0; if (x <= -1550.0) tmp = t_0; elseif (x <= 1.25e-35) tmp = 1.0 / x; else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision]}, If[LessEqual[x, -1550.0], t$95$0, If[LessEqual[x, 1.25e-35], N[(1.0 / x), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{e^{-y}}{x}\\
\mathbf{if}\;x \leq -1550:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;x \leq 1.25 \cdot 10^{-35}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if x < -1550 or 1.24999999999999991e-35 < x Initial program 74.7%
Taylor expanded in x around inf
mul-1-negN/A
lower-neg.f6498.5
Applied rewrites98.5%
if -1550 < x < 1.24999999999999991e-35Initial program 82.5%
Taylor expanded in x around 0
Applied rewrites99.1%
(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 2024230
(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))