
(FPCore (alpha beta) :precision binary64 (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))
double code(double alpha, double beta) {
return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
real(8) function code(alpha, beta)
real(8), intent (in) :: alpha
real(8), intent (in) :: beta
code = (((beta - alpha) / ((alpha + beta) + 2.0d0)) + 1.0d0) / 2.0d0
end function
public static double code(double alpha, double beta) {
return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
def code(alpha, beta): return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0
function code(alpha, beta) return Float64(Float64(Float64(Float64(beta - alpha) / Float64(Float64(alpha + beta) + 2.0)) + 1.0) / 2.0) end
function tmp = code(alpha, beta) tmp = (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0; end
code[alpha_, beta_] := N[(N[(N[(N[(beta - alpha), $MachinePrecision] / N[(N[(alpha + beta), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 13 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (alpha beta) :precision binary64 (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))
double code(double alpha, double beta) {
return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
real(8) function code(alpha, beta)
real(8), intent (in) :: alpha
real(8), intent (in) :: beta
code = (((beta - alpha) / ((alpha + beta) + 2.0d0)) + 1.0d0) / 2.0d0
end function
public static double code(double alpha, double beta) {
return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
def code(alpha, beta): return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0
function code(alpha, beta) return Float64(Float64(Float64(Float64(beta - alpha) / Float64(Float64(alpha + beta) + 2.0)) + 1.0) / 2.0) end
function tmp = code(alpha, beta) tmp = (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0; end
code[alpha_, beta_] := N[(N[(N[(N[(beta - alpha), $MachinePrecision] / N[(N[(alpha + beta), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}
\end{array}
(FPCore (alpha beta) :precision binary64 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ alpha beta))))) (if (<= t_0 -1.0) (/ (+ 1.0 beta) alpha) (/ (+ 1.0 t_0) 2.0))))
double code(double alpha, double beta) {
double t_0 = (beta - alpha) / (2.0 + (alpha + beta));
double tmp;
if (t_0 <= -1.0) {
tmp = (1.0 + beta) / alpha;
} else {
tmp = (1.0 + t_0) / 2.0;
}
return tmp;
}
real(8) function code(alpha, beta)
real(8), intent (in) :: alpha
real(8), intent (in) :: beta
real(8) :: t_0
real(8) :: tmp
t_0 = (beta - alpha) / (2.0d0 + (alpha + beta))
if (t_0 <= (-1.0d0)) then
tmp = (1.0d0 + beta) / alpha
else
tmp = (1.0d0 + t_0) / 2.0d0
end if
code = tmp
end function
public static double code(double alpha, double beta) {
double t_0 = (beta - alpha) / (2.0 + (alpha + beta));
double tmp;
if (t_0 <= -1.0) {
tmp = (1.0 + beta) / alpha;
} else {
tmp = (1.0 + t_0) / 2.0;
}
return tmp;
}
def code(alpha, beta): t_0 = (beta - alpha) / (2.0 + (alpha + beta)) tmp = 0 if t_0 <= -1.0: tmp = (1.0 + beta) / alpha else: tmp = (1.0 + t_0) / 2.0 return tmp
function code(alpha, beta) t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(alpha + beta))) tmp = 0.0 if (t_0 <= -1.0) tmp = Float64(Float64(1.0 + beta) / alpha); else tmp = Float64(Float64(1.0 + t_0) / 2.0); end return tmp end
function tmp_2 = code(alpha, beta) t_0 = (beta - alpha) / (2.0 + (alpha + beta)); tmp = 0.0; if (t_0 <= -1.0) tmp = (1.0 + beta) / alpha; else tmp = (1.0 + t_0) / 2.0; end tmp_2 = tmp; end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(alpha + beta), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1.0], N[(N[(1.0 + beta), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(1.0 + t$95$0), $MachinePrecision] / 2.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{\beta - \alpha}{2 + \left(\alpha + \beta\right)}\\
\mathbf{if}\;t\_0 \leq -1:\\
\;\;\;\;\frac{1 + \beta}{\alpha}\\
\mathbf{else}:\\
\;\;\;\;\frac{1 + t\_0}{2}\\
\end{array}
\end{array}
if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -1Initial program 5.1%
Taylor expanded in alpha around inf
associate-*r/N/A
lower-/.f64N/A
+-commutativeN/A
distribute-lft-inN/A
metadata-evalN/A
associate-*r*N/A
metadata-evalN/A
*-lft-identityN/A
lower-+.f64100.0
Applied rewrites100.0%
if -1 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) Initial program 100.0%
Final simplification100.0%
(FPCore (alpha beta)
:precision binary64
(let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ alpha beta)))))
(if (<= t_0 -1.0)
(/ (+ 1.0 beta) alpha)
(if (<= t_0 0.001)
(fma (/ alpha (- -2.0 alpha)) 0.5 0.5)
(fma (+ 1.0 alpha) (/ -1.0 beta) 1.0)))))
double code(double alpha, double beta) {
double t_0 = (beta - alpha) / (2.0 + (alpha + beta));
double tmp;
if (t_0 <= -1.0) {
tmp = (1.0 + beta) / alpha;
} else if (t_0 <= 0.001) {
tmp = fma((alpha / (-2.0 - alpha)), 0.5, 0.5);
} else {
tmp = fma((1.0 + alpha), (-1.0 / beta), 1.0);
}
return tmp;
}
function code(alpha, beta) t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(alpha + beta))) tmp = 0.0 if (t_0 <= -1.0) tmp = Float64(Float64(1.0 + beta) / alpha); elseif (t_0 <= 0.001) tmp = fma(Float64(alpha / Float64(-2.0 - alpha)), 0.5, 0.5); else tmp = fma(Float64(1.0 + alpha), Float64(-1.0 / beta), 1.0); end return tmp end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(alpha + beta), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1.0], N[(N[(1.0 + beta), $MachinePrecision] / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.001], N[(N[(alpha / N[(-2.0 - alpha), $MachinePrecision]), $MachinePrecision] * 0.5 + 0.5), $MachinePrecision], N[(N[(1.0 + alpha), $MachinePrecision] * N[(-1.0 / beta), $MachinePrecision] + 1.0), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{\beta - \alpha}{2 + \left(\alpha + \beta\right)}\\
\mathbf{if}\;t\_0 \leq -1:\\
\;\;\;\;\frac{1 + \beta}{\alpha}\\
\mathbf{elif}\;t\_0 \leq 0.001:\\
\;\;\;\;\mathsf{fma}\left(\frac{\alpha}{-2 - \alpha}, 0.5, 0.5\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(1 + \alpha, \frac{-1}{\beta}, 1\right)\\
\end{array}
\end{array}
if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -1Initial program 5.3%
Taylor expanded in alpha around inf
associate-*r/N/A
lower-/.f64N/A
+-commutativeN/A
distribute-lft-inN/A
metadata-evalN/A
associate-*r*N/A
metadata-evalN/A
*-lft-identityN/A
lower-+.f64100.0
Applied rewrites100.0%
if -1 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < 1e-3Initial program 98.7%
Taylor expanded in alpha around 0
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
lower-fma.f64N/A
lower-/.f64N/A
+-commutativeN/A
metadata-evalN/A
metadata-evalN/A
sub-negN/A
lower--.f64N/A
metadata-eval95.0
Applied rewrites95.0%
Taylor expanded in beta around 0
sub-negN/A
+-commutativeN/A
distribute-rgt-inN/A
metadata-evalN/A
lower-fma.f64N/A
distribute-neg-frac2N/A
lower-/.f64N/A
distribute-neg-inN/A
metadata-evalN/A
unsub-negN/A
lower--.f6496.4
Applied rewrites96.4%
if 1e-3 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) Initial program 100.0%
Taylor expanded in beta around -inf
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-/.f64N/A
+-commutativeN/A
associate--r+N/A
sub-negN/A
*-lft-identityN/A
distribute-rgt-out--N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
lower-fma.f64N/A
metadata-evalN/A
metadata-eval97.2
Applied rewrites97.2%
Taylor expanded in alpha around 0
Applied rewrites97.2%
Final simplification97.6%
herbie shell --seed 2024230
(FPCore (alpha beta)
:name "Octave 3.8, jcobi/1"
:precision binary64
:pre (and (> alpha -1.0) (> beta -1.0))
(/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))