
(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 5 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 (let* ((t_0 (/ (exp (- y)) x))) (if (<= x -1.25) t_0 (if (<= x 0.5) (/ 1.0 x) t_0))))
double code(double x, double y) {
double t_0 = exp(-y) / x;
double tmp;
if (x <= -1.25) {
tmp = t_0;
} else if (x <= 0.5) {
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 <= (-1.25d0)) then
tmp = t_0
else if (x <= 0.5d0) 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 <= -1.25) {
tmp = t_0;
} else if (x <= 0.5) {
tmp = 1.0 / x;
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = math.exp(-y) / x tmp = 0 if x <= -1.25: tmp = t_0 elif x <= 0.5: 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 <= -1.25) tmp = t_0; elseif (x <= 0.5) 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 <= -1.25) tmp = t_0; elseif (x <= 0.5) 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, -1.25], t$95$0, If[LessEqual[x, 0.5], N[(1.0 / x), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{e^{-y}}{x}\\
\mathbf{if}\;x \leq -1.25:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;x \leq 0.5:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if x < -1.25 or 0.5 < x Initial program 71.6%
Taylor expanded in x around inf
exp-lowering-exp.f64N/A
mul-1-negN/A
neg-lowering-neg.f6499.3
Simplified99.3%
if -1.25 < x < 0.5Initial program 82.3%
Taylor expanded in x around 0
Simplified99.3%
(FPCore (x y) :precision binary64 (if (<= x -1.25) (/ (fma y (fma y (fma y -0.16666666666666666 0.5) -1.0) 1.0) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (x <= -1.25) {
tmp = fma(y, fma(y, fma(y, -0.16666666666666666, 0.5), -1.0), 1.0) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (x <= -1.25) tmp = Float64(fma(y, fma(y, fma(y, -0.16666666666666666, 0.5), -1.0), 1.0) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[x, -1.25], N[(N[(y * N[(y * N[(y * -0.16666666666666666 + 0.5), $MachinePrecision] + -1.0), $MachinePrecision] + 1.0), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.25:\\
\;\;\;\;\frac{\mathsf{fma}\left(y, \mathsf{fma}\left(y, \mathsf{fma}\left(y, -0.16666666666666666, 0.5\right), -1\right), 1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -1.25Initial program 65.8%
Taylor expanded in x around inf
exp-lowering-exp.f64N/A
mul-1-negN/A
neg-lowering-neg.f64100.0
Simplified100.0%
Taylor expanded in y around 0
+-commutativeN/A
metadata-evalN/A
cancel-sign-sub-invN/A
accelerator-lowering-fma.f64N/A
sub-negN/A
cancel-sign-sub-invN/A
metadata-evalN/A
metadata-evalN/A
accelerator-lowering-fma.f64N/A
+-commutativeN/A
*-commutativeN/A
accelerator-lowering-fma.f6473.9
Simplified73.9%
if -1.25 < x Initial program 81.3%
Taylor expanded in x around 0
Simplified86.3%
(FPCore (x y) :precision binary64 (if (<= x -0.85) (/ (fma y (fma y 0.5 -1.0) 1.0) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (x <= -0.85) {
tmp = fma(y, fma(y, 0.5, -1.0), 1.0) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
function code(x, y) tmp = 0.0 if (x <= -0.85) tmp = Float64(fma(y, fma(y, 0.5, -1.0), 1.0) / x); else tmp = Float64(1.0 / x); end return tmp end
code[x_, y_] := If[LessEqual[x, -0.85], N[(N[(y * N[(y * 0.5 + -1.0), $MachinePrecision] + 1.0), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -0.85:\\
\;\;\;\;\frac{\mathsf{fma}\left(y, \mathsf{fma}\left(y, 0.5, -1\right), 1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -0.849999999999999978Initial program 65.8%
Taylor expanded in x around inf
exp-lowering-exp.f64N/A
mul-1-negN/A
neg-lowering-neg.f64100.0
Simplified100.0%
Taylor expanded in y around 0
+-commutativeN/A
accelerator-lowering-fma.f64N/A
sub-negN/A
*-commutativeN/A
metadata-evalN/A
accelerator-lowering-fma.f6470.4
Simplified70.4%
if -0.849999999999999978 < x Initial program 81.3%
Taylor expanded in x around 0
Simplified86.3%
(FPCore (x y) :precision binary64 (if (<= y 3.5e+35) (/ 1.0 x) (/ x (* x x))))
double code(double x, double y) {
double tmp;
if (y <= 3.5e+35) {
tmp = 1.0 / x;
} else {
tmp = x / (x * x);
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= 3.5d+35) then
tmp = 1.0d0 / x
else
tmp = x / (x * x)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= 3.5e+35) {
tmp = 1.0 / x;
} else {
tmp = x / (x * x);
}
return tmp;
}
def code(x, y): tmp = 0 if y <= 3.5e+35: tmp = 1.0 / x else: tmp = x / (x * x) return tmp
function code(x, y) tmp = 0.0 if (y <= 3.5e+35) tmp = Float64(1.0 / x); else tmp = Float64(x / Float64(x * x)); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= 3.5e+35) tmp = 1.0 / x; else tmp = x / (x * x); end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, 3.5e+35], N[(1.0 / x), $MachinePrecision], N[(x / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 3.5 \cdot 10^{+35}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{x}{x \cdot x}\\
\end{array}
\end{array}
if y < 3.5000000000000001e35Initial program 83.2%
Taylor expanded in x around 0
Simplified82.0%
if 3.5000000000000001e35 < y Initial program 42.5%
Taylor expanded in y around 0
+-commutativeN/A
mul-1-negN/A
unsub-negN/A
--lowering--.f64N/A
/-lowering-/.f64N/A
/-lowering-/.f642.3
Simplified2.3%
frac-subN/A
/-lowering-/.f64N/A
*-lft-identityN/A
--lowering--.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-lowering-*.f647.8
Applied egg-rr7.8%
Taylor expanded in y around 0
Simplified58.5%
(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 76.3%
Taylor expanded in x around 0
Simplified74.8%
(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 2024204
(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))