
(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 (<= x -1.38e+59)
(/ (exp (- y)) x)
(if (<= x 2.0)
(/ (pow (exp x) (log (/ x (+ x y)))) x)
(/ (/ 1.0 x) (exp y)))))
double code(double x, double y) {
double tmp;
if (x <= -1.38e+59) {
tmp = exp(-y) / x;
} else if (x <= 2.0) {
tmp = pow(exp(x), log((x / (x + y)))) / x;
} else {
tmp = (1.0 / x) / exp(y);
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-1.38d+59)) then
tmp = exp(-y) / x
else if (x <= 2.0d0) then
tmp = (exp(x) ** log((x / (x + y)))) / x
else
tmp = (1.0d0 / x) / exp(y)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -1.38e+59) {
tmp = Math.exp(-y) / x;
} else if (x <= 2.0) {
tmp = Math.pow(Math.exp(x), Math.log((x / (x + y)))) / x;
} else {
tmp = (1.0 / x) / Math.exp(y);
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.38e+59: tmp = math.exp(-y) / x elif x <= 2.0: tmp = math.pow(math.exp(x), math.log((x / (x + y)))) / x else: tmp = (1.0 / x) / math.exp(y) return tmp
function code(x, y) tmp = 0.0 if (x <= -1.38e+59) tmp = Float64(exp(Float64(-y)) / x); elseif (x <= 2.0) tmp = Float64((exp(x) ^ log(Float64(x / Float64(x + y)))) / x); else tmp = Float64(Float64(1.0 / x) / exp(y)); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.38e+59) tmp = exp(-y) / x; elseif (x <= 2.0) tmp = (exp(x) ^ log((x / (x + y)))) / x; else tmp = (1.0 / x) / exp(y); end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.38e+59], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], If[LessEqual[x, 2.0], N[(N[Power[N[Exp[x], $MachinePrecision], N[Log[N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision], N[(N[(1.0 / x), $MachinePrecision] / N[Exp[y], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.38 \cdot 10^{+59}:\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{elif}\;x \leq 2:\\
\;\;\;\;\frac{{\left(e^{x}\right)}^{\log \left(\frac{x}{x + y}\right)}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{1}{x}}{e^{y}}\\
\end{array}
\end{array}
if x < -1.38e59Initial program 61.0%
*-commutative61.0%
exp-to-pow61.0%
Simplified61.0%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
if -1.38e59 < x < 2Initial program 85.6%
exp-prod99.8%
Simplified99.8%
if 2 < x Initial program 74.9%
*-commutative74.9%
exp-to-pow74.9%
Simplified74.9%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
clear-num100.0%
inv-pow100.0%
exp-neg100.0%
associate-/r/100.0%
/-rgt-identity100.0%
Applied egg-rr100.0%
Taylor expanded in x around 0 100.0%
associate-/r*100.0%
Simplified100.0%
(FPCore (x y) :precision binary64 (if (<= x -31.5) (/ (exp (- y)) x) (if (<= x 0.88) (/ 1.0 x) (/ (/ 1.0 x) (exp y)))))
double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = exp(-y) / x;
} else if (x <= 0.88) {
tmp = 1.0 / x;
} else {
tmp = (1.0 / x) / exp(y);
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-31.5d0)) then
tmp = exp(-y) / x
else if (x <= 0.88d0) then
tmp = 1.0d0 / x
else
tmp = (1.0d0 / x) / exp(y)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = Math.exp(-y) / x;
} else if (x <= 0.88) {
tmp = 1.0 / x;
} else {
tmp = (1.0 / x) / Math.exp(y);
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -31.5: tmp = math.exp(-y) / x elif x <= 0.88: tmp = 1.0 / x else: tmp = (1.0 / x) / math.exp(y) return tmp
function code(x, y) tmp = 0.0 if (x <= -31.5) tmp = Float64(exp(Float64(-y)) / x); elseif (x <= 0.88) tmp = Float64(1.0 / x); else tmp = Float64(Float64(1.0 / x) / exp(y)); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -31.5) tmp = exp(-y) / x; elseif (x <= 0.88) tmp = 1.0 / x; else tmp = (1.0 / x) / exp(y); end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -31.5], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], If[LessEqual[x, 0.88], N[(1.0 / x), $MachinePrecision], N[(N[(1.0 / x), $MachinePrecision] / N[Exp[y], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -31.5:\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{elif}\;x \leq 0.88:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{1}{x}}{e^{y}}\\
\end{array}
\end{array}
if x < -31.5Initial program 66.5%
*-commutative66.5%
exp-to-pow66.5%
Simplified66.5%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
if -31.5 < x < 0.880000000000000004Initial program 84.1%
exp-prod99.8%
Simplified99.8%
Taylor expanded in x around 0 98.7%
if 0.880000000000000004 < x Initial program 74.9%
*-commutative74.9%
exp-to-pow74.9%
Simplified74.9%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
clear-num100.0%
inv-pow100.0%
exp-neg100.0%
associate-/r/100.0%
/-rgt-identity100.0%
Applied egg-rr100.0%
Taylor expanded in x around 0 100.0%
associate-/r*100.0%
Simplified100.0%
(FPCore (x y) :precision binary64 (if (or (<= x -31.5) (not (<= x 0.12))) (/ (exp (- y)) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if ((x <= -31.5) || !(x <= 0.12)) {
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 <= (-31.5d0)) .or. (.not. (x <= 0.12d0))) 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 <= -31.5) || !(x <= 0.12)) {
tmp = Math.exp(-y) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -31.5) or not (x <= 0.12): tmp = math.exp(-y) / x else: tmp = 1.0 / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -31.5) || !(x <= 0.12)) 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 <= -31.5) || ~((x <= 0.12))) tmp = exp(-y) / x; else tmp = 1.0 / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -31.5], N[Not[LessEqual[x, 0.12]], $MachinePrecision]], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -31.5 \lor \neg \left(x \leq 0.12\right):\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -31.5 or 0.12 < x Initial program 70.5%
*-commutative70.5%
exp-to-pow70.5%
Simplified70.5%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
if -31.5 < x < 0.12Initial program 84.1%
exp-prod99.8%
Simplified99.8%
Taylor expanded in x around 0 98.7%
Final simplification99.4%
(FPCore (x y) :precision binary64 (if (<= x -31.5) (/ (+ 1.0 (* y (+ (/ (* y (+ 0.5 (* x 0.5))) x) -1.0))) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = (1.0 + (y * (((y * (0.5 + (x * 0.5))) / x) + -1.0))) / 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 <= (-31.5d0)) then
tmp = (1.0d0 + (y * (((y * (0.5d0 + (x * 0.5d0))) / x) + (-1.0d0)))) / x
else
tmp = 1.0d0 / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = (1.0 + (y * (((y * (0.5 + (x * 0.5))) / x) + -1.0))) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -31.5: tmp = (1.0 + (y * (((y * (0.5 + (x * 0.5))) / x) + -1.0))) / x else: tmp = 1.0 / x return tmp
function code(x, y) tmp = 0.0 if (x <= -31.5) tmp = Float64(Float64(1.0 + Float64(y * Float64(Float64(Float64(y * Float64(0.5 + Float64(x * 0.5))) / x) + -1.0))) / x); else tmp = Float64(1.0 / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -31.5) tmp = (1.0 + (y * (((y * (0.5 + (x * 0.5))) / x) + -1.0))) / x; else tmp = 1.0 / x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -31.5], N[(N[(1.0 + N[(y * N[(N[(N[(y * N[(0.5 + N[(x * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -31.5:\\
\;\;\;\;\frac{1 + y \cdot \left(\frac{y \cdot \left(0.5 + x \cdot 0.5\right)}{x} + -1\right)}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -31.5Initial program 66.5%
exp-prod66.5%
Simplified66.5%
Taylor expanded in y around 0 64.1%
Taylor expanded in x around 0 69.0%
+-commutative69.0%
associate-*r*69.0%
distribute-rgt-out69.0%
*-commutative69.0%
Simplified69.0%
if -31.5 < x Initial program 80.6%
exp-prod90.2%
Simplified90.2%
Taylor expanded in x around 0 81.9%
Final simplification78.0%
(FPCore (x y) :precision binary64 (if (<= x -31.5) (/ (/ (- x (* x y)) x) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = ((x - (x * y)) / x) / 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 <= (-31.5d0)) then
tmp = ((x - (x * y)) / x) / x
else
tmp = 1.0d0 / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -31.5) {
tmp = ((x - (x * y)) / x) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -31.5: tmp = ((x - (x * y)) / x) / x else: tmp = 1.0 / x return tmp
function code(x, y) tmp = 0.0 if (x <= -31.5) tmp = Float64(Float64(Float64(x - Float64(x * y)) / x) / x); else tmp = Float64(1.0 / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -31.5) tmp = ((x - (x * y)) / x) / x; else tmp = 1.0 / x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -31.5], N[(N[(N[(x - N[(x * y), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -31.5:\\
\;\;\;\;\frac{\frac{x - x \cdot y}{x}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -31.5Initial program 66.5%
exp-prod66.5%
Simplified66.5%
Taylor expanded in y around 0 49.5%
+-commutative49.5%
mul-1-neg49.5%
unsub-neg49.5%
Simplified49.5%
frac-sub35.5%
associate-/r*65.4%
*-un-lft-identity65.4%
*-commutative65.4%
Applied egg-rr65.4%
if -31.5 < x Initial program 80.6%
exp-prod90.2%
Simplified90.2%
Taylor expanded in x around 0 81.9%
Final simplification76.9%
(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%
exp-prod83.0%
Simplified83.0%
Taylor expanded in x around 0 71.9%
(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 2024087
(FPCore (x y)
:name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, F"
:precision binary64
:alt
(if (< y -3.7311844206647956e+94) (/ (exp (/ -1.0 y)) x) (if (< y 2.817959242728288e+37) (/ (pow (/ x (+ y x)) x) x) (if (< y 2.347387415166998e+178) (log (exp (/ (pow (/ x (+ y x)) x) x))) (/ (exp (/ -1.0 y)) x))))
(/ (exp (* x (log (/ x (+ x y))))) x))