
(FPCore (x) :precision binary64 (* 0.70711 (- (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* x (+ 0.99229 (* x 0.04481))))) x)))
double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.70711d0 * (((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + (x * (0.99229d0 + (x * 0.04481d0))))) - x)
end function
public static double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
def code(x): return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x)
function code(x) return Float64(0.70711 * Float64(Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(x * Float64(0.99229 + Float64(x * 0.04481))))) - x)) end
function tmp = code(x) tmp = 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x); end
code[x_] := N[(0.70711 * N[(N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * N[(0.99229 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.70711 \cdot \left(\frac{2.30753 + x \cdot 0.27061}{1 + x \cdot \left(0.99229 + x \cdot 0.04481\right)} - x\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (* 0.70711 (- (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* x (+ 0.99229 (* x 0.04481))))) x)))
double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.70711d0 * (((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + (x * (0.99229d0 + (x * 0.04481d0))))) - x)
end function
public static double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
def code(x): return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x)
function code(x) return Float64(0.70711 * Float64(Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(x * Float64(0.99229 + Float64(x * 0.04481))))) - x)) end
function tmp = code(x) tmp = 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x); end
code[x_] := N[(0.70711 * N[(N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * N[(0.99229 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.70711 \cdot \left(\frac{2.30753 + x \cdot 0.27061}{1 + x \cdot \left(0.99229 + x \cdot 0.04481\right)} - x\right)
\end{array}
(FPCore (x) :precision binary64 (fma x -0.70711 (/ (fma x 0.1913510371 1.6316775383) (fma x (fma x 0.04481 0.99229) 1.0))))
double code(double x) {
return fma(x, -0.70711, (fma(x, 0.1913510371, 1.6316775383) / fma(x, fma(x, 0.04481, 0.99229), 1.0)));
}
function code(x) return fma(x, -0.70711, Float64(fma(x, 0.1913510371, 1.6316775383) / fma(x, fma(x, 0.04481, 0.99229), 1.0))) end
code[x_] := N[(x * -0.70711 + N[(N[(x * 0.1913510371 + 1.6316775383), $MachinePrecision] / N[(x * N[(x * 0.04481 + 0.99229), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x, -0.70711, \frac{\mathsf{fma}\left(x, 0.1913510371, 1.6316775383\right)}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.04481, 0.99229\right), 1\right)}\right)
\end{array}
(FPCore (x) :precision binary64 (* 0.70711 (- (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* x (+ 0.99229 (* x 0.04481))))) x)))
double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.70711d0 * (((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + (x * (0.99229d0 + (x * 0.04481d0))))) - x)
end function
public static double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x);
}
def code(x): return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x)
function code(x) return Float64(0.70711 * Float64(Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(x * Float64(0.99229 + Float64(x * 0.04481))))) - x)) end
function tmp = code(x) tmp = 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + (x * 0.04481))))) - x); end
code[x_] := N[(0.70711 * N[(N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * N[(0.99229 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.70711 \cdot \left(\frac{2.30753 + x \cdot 0.27061}{1 + x \cdot \left(0.99229 + x \cdot 0.04481\right)} - x\right)
\end{array}
(FPCore (x) :precision binary64 (* 0.70711 (- (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* x 0.99229))) x)))
double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * 0.99229))) - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.70711d0 * (((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + (x * 0.99229d0))) - x)
end function
public static double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * 0.99229))) - x);
}
def code(x): return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * 0.99229))) - x)
function code(x) return Float64(0.70711 * Float64(Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(x * 0.99229))) - x)) end
function tmp = code(x) tmp = 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * 0.99229))) - x); end
code[x_] := N[(0.70711 * N[(N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * 0.99229), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.70711 \cdot \left(\frac{2.30753 + x \cdot 0.27061}{1 + x \cdot 0.99229} - x\right)
\end{array}
(FPCore (x) :precision binary64 (if (or (<= x -1.05) (not (<= x 0.72))) (* 0.70711 (- (/ 6.039053782637804 x) x)) (+ 1.6316775383 (* x -2.134856267379707))))
double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 0.72)) {
tmp = 0.70711 * ((6.039053782637804 / x) - x);
} else {
tmp = 1.6316775383 + (x * -2.134856267379707);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.05d0)) .or. (.not. (x <= 0.72d0))) then
tmp = 0.70711d0 * ((6.039053782637804d0 / x) - x)
else
tmp = 1.6316775383d0 + (x * (-2.134856267379707d0))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 0.72)) {
tmp = 0.70711 * ((6.039053782637804 / x) - x);
} else {
tmp = 1.6316775383 + (x * -2.134856267379707);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.05) or not (x <= 0.72): tmp = 0.70711 * ((6.039053782637804 / x) - x) else: tmp = 1.6316775383 + (x * -2.134856267379707) return tmp
function code(x) tmp = 0.0 if ((x <= -1.05) || !(x <= 0.72)) tmp = Float64(0.70711 * Float64(Float64(6.039053782637804 / x) - x)); else tmp = Float64(1.6316775383 + Float64(x * -2.134856267379707)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.05) || ~((x <= 0.72))) tmp = 0.70711 * ((6.039053782637804 / x) - x); else tmp = 1.6316775383 + (x * -2.134856267379707); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.05], N[Not[LessEqual[x, 0.72]], $MachinePrecision]], N[(0.70711 * N[(N[(6.039053782637804 / x), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision], N[(1.6316775383 + N[(x * -2.134856267379707), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.05 \lor \neg \left(x \leq 0.72\right):\\
\;\;\;\;0.70711 \cdot \left(\frac{6.039053782637804}{x} - x\right)\\
\mathbf{else}:\\
\;\;\;\;1.6316775383 + x \cdot -2.134856267379707\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 (if (or (<= x -1.05) (not (<= x 1.1))) (* x -0.70711) (+ 1.6316775383 (* x -2.134856267379707))))
double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 1.1)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383 + (x * -2.134856267379707);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.05d0)) .or. (.not. (x <= 1.1d0))) then
tmp = x * (-0.70711d0)
else
tmp = 1.6316775383d0 + (x * (-2.134856267379707d0))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 1.1)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383 + (x * -2.134856267379707);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.05) or not (x <= 1.1): tmp = x * -0.70711 else: tmp = 1.6316775383 + (x * -2.134856267379707) return tmp
function code(x) tmp = 0.0 if ((x <= -1.05) || !(x <= 1.1)) tmp = Float64(x * -0.70711); else tmp = Float64(1.6316775383 + Float64(x * -2.134856267379707)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.05) || ~((x <= 1.1))) tmp = x * -0.70711; else tmp = 1.6316775383 + (x * -2.134856267379707); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.05], N[Not[LessEqual[x, 1.1]], $MachinePrecision]], N[(x * -0.70711), $MachinePrecision], N[(1.6316775383 + N[(x * -2.134856267379707), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.05 \lor \neg \left(x \leq 1.1\right):\\
\;\;\;\;x \cdot -0.70711\\
\mathbf{else}:\\
\;\;\;\;1.6316775383 + x \cdot -2.134856267379707\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 (if (or (<= x -1.05) (not (<= x 1.2))) (* x -0.70711) 1.6316775383))
double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 1.2)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.05d0)) .or. (.not. (x <= 1.2d0))) then
tmp = x * (-0.70711d0)
else
tmp = 1.6316775383d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.05) || !(x <= 1.2)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383;
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.05) or not (x <= 1.2): tmp = x * -0.70711 else: tmp = 1.6316775383 return tmp
function code(x) tmp = 0.0 if ((x <= -1.05) || !(x <= 1.2)) tmp = Float64(x * -0.70711); else tmp = 1.6316775383; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.05) || ~((x <= 1.2))) tmp = x * -0.70711; else tmp = 1.6316775383; end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.05], N[Not[LessEqual[x, 1.2]], $MachinePrecision]], N[(x * -0.70711), $MachinePrecision], 1.6316775383]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.05 \lor \neg \left(x \leq 1.2\right):\\
\;\;\;\;x \cdot -0.70711\\
\mathbf{else}:\\
\;\;\;\;1.6316775383\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 0.1928378166664987)
double code(double x) {
return 0.1928378166664987;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.1928378166664987d0
end function
public static double code(double x) {
return 0.1928378166664987;
}
def code(x): return 0.1928378166664987
function code(x) return 0.1928378166664987 end
function tmp = code(x) tmp = 0.1928378166664987; end
code[x_] := 0.1928378166664987
\begin{array}{l}
\\
0.1928378166664987
\end{array}
(FPCore (x) :precision binary64 1.6316775383)
double code(double x) {
return 1.6316775383;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.6316775383d0
end function
public static double code(double x) {
return 1.6316775383;
}
def code(x): return 1.6316775383
function code(x) return 1.6316775383 end
function tmp = code(x) tmp = 1.6316775383; end
code[x_] := 1.6316775383
\begin{array}{l}
\\
1.6316775383
\end{array}
herbie shell --seed 2024008
(FPCore (x)
:name "Numeric.SpecFunctions:invErfc from math-functions-0.1.5.2, B"
:precision binary64
(* 0.70711 (- (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* x (+ 0.99229 (* x 0.04481))))) x)))