
(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 -1e+66) (not (<= x 20.0))) (/ (exp (- y)) x) (/ (pow (exp x) (log (/ x (+ x y)))) x)))
double code(double x, double y) {
double tmp;
if ((x <= -1e+66) || !(x <= 20.0)) {
tmp = exp(-y) / x;
} else {
tmp = pow(exp(x), log((x / (x + 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 <= (-1d+66)) .or. (.not. (x <= 20.0d0))) then
tmp = exp(-y) / x
else
tmp = (exp(x) ** log((x / (x + y)))) / x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -1e+66) || !(x <= 20.0)) {
tmp = Math.exp(-y) / x;
} else {
tmp = Math.pow(Math.exp(x), Math.log((x / (x + y)))) / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -1e+66) or not (x <= 20.0): tmp = math.exp(-y) / x else: tmp = math.pow(math.exp(x), math.log((x / (x + y)))) / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -1e+66) || !(x <= 20.0)) tmp = Float64(exp(Float64(-y)) / x); else tmp = Float64((exp(x) ^ log(Float64(x / Float64(x + y)))) / x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -1e+66) || ~((x <= 20.0))) tmp = exp(-y) / x; else tmp = (exp(x) ^ log((x / (x + y)))) / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -1e+66], N[Not[LessEqual[x, 20.0]], $MachinePrecision]], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], N[(N[Power[N[Exp[x], $MachinePrecision], N[Log[N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{+66} \lor \neg \left(x \leq 20\right):\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{{\left(e^{x}\right)}^{\log \left(\frac{x}{x + y}\right)}}{x}\\
\end{array}
\end{array}
if x < -9.99999999999999945e65 or 20 < x Initial program 74.0%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
if -9.99999999999999945e65 < x < 20Initial program 93.7%
exp-prod99.6%
Simplified99.6%
Final simplification99.8%
(FPCore (x y) :precision binary64 (if (or (<= x -14800.0) (not (<= x 0.26))) (/ (exp (- y)) x) (/ 1.0 x)))
double code(double x, double y) {
double tmp;
if ((x <= -14800.0) || !(x <= 0.26)) {
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 <= (-14800.0d0)) .or. (.not. (x <= 0.26d0))) 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 <= -14800.0) || !(x <= 0.26)) {
tmp = Math.exp(-y) / x;
} else {
tmp = 1.0 / x;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -14800.0) or not (x <= 0.26): tmp = math.exp(-y) / x else: tmp = 1.0 / x return tmp
function code(x, y) tmp = 0.0 if ((x <= -14800.0) || !(x <= 0.26)) 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 <= -14800.0) || ~((x <= 0.26))) tmp = exp(-y) / x; else tmp = 1.0 / x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -14800.0], N[Not[LessEqual[x, 0.26]], $MachinePrecision]], N[(N[Exp[(-y)], $MachinePrecision] / x), $MachinePrecision], N[(1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -14800 \lor \neg \left(x \leq 0.26\right):\\
\;\;\;\;\frac{e^{-y}}{x}\\
\mathbf{else}:\\
\;\;\;\;\frac{1}{x}\\
\end{array}
\end{array}
if x < -14800 or 0.26000000000000001 < x Initial program 76.1%
Taylor expanded in x around inf 100.0%
mul-1-neg100.0%
Simplified100.0%
if -14800 < x < 0.26000000000000001Initial program 93.0%
Taylor expanded in x around 0 97.8%
Final simplification99.1%
(FPCore (x y) :precision binary64 (if (<= y -1.35e+154) (/ (/ (- 1.0 (* y y)) x) (+ y 1.0)) (if (<= y 1.5e+54) (/ 1.0 x) 0.0)))
double code(double x, double y) {
double tmp;
if (y <= -1.35e+154) {
tmp = ((1.0 - (y * y)) / x) / (y + 1.0);
} else if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-1.35d+154)) then
tmp = ((1.0d0 - (y * y)) / x) / (y + 1.0d0)
else if (y <= 1.5d+54) then
tmp = 1.0d0 / x
else
tmp = 0.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -1.35e+154) {
tmp = ((1.0 - (y * y)) / x) / (y + 1.0);
} else if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -1.35e+154: tmp = ((1.0 - (y * y)) / x) / (y + 1.0) elif y <= 1.5e+54: tmp = 1.0 / x else: tmp = 0.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -1.35e+154) tmp = Float64(Float64(Float64(1.0 - Float64(y * y)) / x) / Float64(y + 1.0)); elseif (y <= 1.5e+54) tmp = Float64(1.0 / x); else tmp = 0.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -1.35e+154) tmp = ((1.0 - (y * y)) / x) / (y + 1.0); elseif (y <= 1.5e+54) tmp = 1.0 / x; else tmp = 0.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -1.35e+154], N[(N[(N[(1.0 - N[(y * y), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / N[(y + 1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.5e+54], N[(1.0 / x), $MachinePrecision], 0.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.35 \cdot 10^{+154}:\\
\;\;\;\;\frac{\frac{1 - y \cdot y}{x}}{y + 1}\\
\mathbf{elif}\;y \leq 1.5 \cdot 10^{+54}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}
\end{array}
if y < -1.35000000000000003e154Initial program 61.7%
exp-prod76.4%
Simplified76.4%
Taylor expanded in x around inf 4.4%
mul-1-neg4.4%
unsub-neg4.4%
Simplified4.4%
clear-num4.4%
associate-/r/4.4%
Applied egg-rr4.4%
flip--77.6%
associate-*r/77.6%
metadata-eval77.6%
Applied egg-rr77.6%
Taylor expanded in x around 0 77.6%
unpow277.6%
Simplified77.6%
if -1.35000000000000003e154 < y < 1.4999999999999999e54Initial program 90.2%
Taylor expanded in x around 0 88.1%
if 1.4999999999999999e54 < y Initial program 66.2%
exp-prod71.6%
Simplified71.6%
Taylor expanded in x around inf 2.2%
mul-1-neg2.2%
unsub-neg2.2%
Simplified2.2%
clear-num2.2%
associate-/r/2.2%
Applied egg-rr2.2%
expm1-log1p-u1.4%
expm1-udef29.1%
log1p-udef29.1%
add-exp-log29.9%
associate-*l/29.9%
*-un-lft-identity29.9%
Applied egg-rr29.9%
Taylor expanded in x around inf 61.0%
Final simplification82.3%
(FPCore (x y) :precision binary64 (if (<= y -8e+206) (/ (/ (- y) (/ x y)) (+ y 1.0)) (if (<= y 1.5e+54) (/ 1.0 x) 0.0)))
double code(double x, double y) {
double tmp;
if (y <= -8e+206) {
tmp = (-y / (x / y)) / (y + 1.0);
} else if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-8d+206)) then
tmp = (-y / (x / y)) / (y + 1.0d0)
else if (y <= 1.5d+54) then
tmp = 1.0d0 / x
else
tmp = 0.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -8e+206) {
tmp = (-y / (x / y)) / (y + 1.0);
} else if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -8e+206: tmp = (-y / (x / y)) / (y + 1.0) elif y <= 1.5e+54: tmp = 1.0 / x else: tmp = 0.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -8e+206) tmp = Float64(Float64(Float64(-y) / Float64(x / y)) / Float64(y + 1.0)); elseif (y <= 1.5e+54) tmp = Float64(1.0 / x); else tmp = 0.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -8e+206) tmp = (-y / (x / y)) / (y + 1.0); elseif (y <= 1.5e+54) tmp = 1.0 / x; else tmp = 0.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -8e+206], N[(N[((-y) / N[(x / y), $MachinePrecision]), $MachinePrecision] / N[(y + 1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.5e+54], N[(1.0 / x), $MachinePrecision], 0.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -8 \cdot 10^{+206}:\\
\;\;\;\;\frac{\frac{-y}{\frac{x}{y}}}{y + 1}\\
\mathbf{elif}\;y \leq 1.5 \cdot 10^{+54}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}
\end{array}
if y < -8.0000000000000003e206Initial program 73.0%
exp-prod85.9%
Simplified85.9%
Taylor expanded in x around inf 4.8%
mul-1-neg4.8%
unsub-neg4.8%
Simplified4.8%
clear-num4.8%
associate-/r/4.8%
Applied egg-rr4.8%
flip--87.1%
associate-*r/87.1%
metadata-eval87.1%
Applied egg-rr87.1%
Taylor expanded in y around inf 87.1%
mul-1-neg87.1%
unpow287.1%
associate-/l*52.4%
Simplified52.4%
if -8.0000000000000003e206 < y < 1.4999999999999999e54Initial program 87.8%
Taylor expanded in x around 0 85.3%
if 1.4999999999999999e54 < y Initial program 66.2%
exp-prod71.6%
Simplified71.6%
Taylor expanded in x around inf 2.2%
mul-1-neg2.2%
unsub-neg2.2%
Simplified2.2%
clear-num2.2%
associate-/r/2.2%
Applied egg-rr2.2%
expm1-log1p-u1.4%
expm1-udef29.1%
log1p-udef29.1%
add-exp-log29.9%
associate-*l/29.9%
*-un-lft-identity29.9%
Applied egg-rr29.9%
Taylor expanded in x around inf 61.0%
Final simplification79.2%
(FPCore (x y) :precision binary64 (if (<= y 1.5e+54) (/ 1.0 x) 0.0))
double code(double x, double y) {
double tmp;
if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= 1.5d+54) then
tmp = 1.0d0 / x
else
tmp = 0.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= 1.5e+54) {
tmp = 1.0 / x;
} else {
tmp = 0.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= 1.5e+54: tmp = 1.0 / x else: tmp = 0.0 return tmp
function code(x, y) tmp = 0.0 if (y <= 1.5e+54) tmp = Float64(1.0 / x); else tmp = 0.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= 1.5e+54) tmp = 1.0 / x; else tmp = 0.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, 1.5e+54], N[(1.0 / x), $MachinePrecision], 0.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 1.5 \cdot 10^{+54}:\\
\;\;\;\;\frac{1}{x}\\
\mathbf{else}:\\
\;\;\;\;0\\
\end{array}
\end{array}
if y < 1.4999999999999999e54Initial program 86.8%
Taylor expanded in x around 0 80.7%
if 1.4999999999999999e54 < y Initial program 66.2%
exp-prod71.6%
Simplified71.6%
Taylor expanded in x around inf 2.2%
mul-1-neg2.2%
unsub-neg2.2%
Simplified2.2%
clear-num2.2%
associate-/r/2.2%
Applied egg-rr2.2%
expm1-log1p-u1.4%
expm1-udef29.1%
log1p-udef29.1%
add-exp-log29.9%
associate-*l/29.9%
*-un-lft-identity29.9%
Applied egg-rr29.9%
Taylor expanded in x around inf 61.0%
Final simplification77.2%
(FPCore (x y) :precision binary64 0.0)
double code(double x, double y) {
return 0.0;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 0.0d0
end function
public static double code(double x, double y) {
return 0.0;
}
def code(x, y): return 0.0
function code(x, y) return 0.0 end
function tmp = code(x, y) tmp = 0.0; end
code[x_, y_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 83.2%
exp-prod86.0%
Simplified86.0%
Taylor expanded in x around inf 59.6%
mul-1-neg59.6%
unsub-neg59.6%
Simplified59.6%
clear-num59.6%
associate-/r/59.6%
Applied egg-rr59.6%
expm1-log1p-u43.4%
expm1-udef19.3%
log1p-udef19.3%
add-exp-log35.5%
associate-*l/35.5%
*-un-lft-identity35.5%
Applied egg-rr35.5%
Taylor expanded in x around inf 14.6%
Final simplification14.6%
(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 2023271
(FPCore (x y)
:name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, F"
:precision binary64
:herbie-target
(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))