
(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 6 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
(*
0.70711
(-
(/
(+ 2.30753 (* x 0.27061))
(+ 1.0 (* x (+ 0.99229 (+ (+ 1.0 (* x 0.04481)) -1.0)))))
x)))
double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + ((1.0 + (x * 0.04481)) + -1.0))))) - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.70711d0 * (((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + (x * (0.99229d0 + ((1.0d0 + (x * 0.04481d0)) + (-1.0d0)))))) - x)
end function
public static double code(double x) {
return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + ((1.0 + (x * 0.04481)) + -1.0))))) - x);
}
def code(x): return 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + ((1.0 + (x * 0.04481)) + -1.0))))) - 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(Float64(1.0 + Float64(x * 0.04481)) + -1.0))))) - x)) end
function tmp = code(x) tmp = 0.70711 * (((2.30753 + (x * 0.27061)) / (1.0 + (x * (0.99229 + ((1.0 + (x * 0.04481)) + -1.0))))) - 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[(N[(1.0 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision] + -1.0), $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 + \left(\left(1 + x \cdot 0.04481\right) + -1\right)\right)} - x\right)
\end{array}
Initial program 99.9%
expm1-log1p-u76.9%
expm1-undefine76.9%
Applied egg-rr76.9%
log1p-undefine76.9%
rem-exp-log99.9%
Applied egg-rr99.9%
Final simplification99.9%
(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}
Initial program 99.9%
Final simplification99.9%
(FPCore (x) :precision binary64 (if (or (<= x -1.06) (not (<= x 1.15))) (* x -0.70711) (+ 1.6316775383 (* x -2.134856267379707))))
double code(double x) {
double tmp;
if ((x <= -1.06) || !(x <= 1.15)) {
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 <= (-1.06d0)) .or. (.not. (x <= 1.15d0))) 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 <= -1.06) || !(x <= 1.15)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383 + (x * -2.134856267379707);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.06) or not (x <= 1.15): tmp = x * -0.70711 else: tmp = 1.6316775383 + (x * -2.134856267379707) return tmp
function code(x) tmp = 0.0 if ((x <= -1.06) || !(x <= 1.15)) 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 <= -1.06) || ~((x <= 1.15))) tmp = x * -0.70711; else tmp = 1.6316775383 + (x * -2.134856267379707); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.06], N[Not[LessEqual[x, 1.15]], $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 -1.06 \lor \neg \left(x \leq 1.15\right):\\
\;\;\;\;x \cdot -0.70711\\
\mathbf{else}:\\
\;\;\;\;1.6316775383 + x \cdot -2.134856267379707\\
\end{array}
\end{array}
if x < -1.0600000000000001 or 1.1499999999999999 < x Initial program 99.8%
Taylor expanded in x around inf 97.9%
*-commutative97.9%
Simplified97.9%
if -1.0600000000000001 < x < 1.1499999999999999Initial program 99.9%
Taylor expanded in x around 0 97.7%
*-commutative97.7%
Simplified97.7%
Final simplification97.8%
(FPCore (x) :precision binary64 (if (<= x -1.06) (* 0.70711 (- (/ 6.039053782637804 x) x)) (if (<= x 1.15) (+ 1.6316775383 (* x -2.134856267379707)) (* x -0.70711))))
double code(double x) {
double tmp;
if (x <= -1.06) {
tmp = 0.70711 * ((6.039053782637804 / x) - x);
} else if (x <= 1.15) {
tmp = 1.6316775383 + (x * -2.134856267379707);
} else {
tmp = x * -0.70711;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= (-1.06d0)) then
tmp = 0.70711d0 * ((6.039053782637804d0 / x) - x)
else if (x <= 1.15d0) then
tmp = 1.6316775383d0 + (x * (-2.134856267379707d0))
else
tmp = x * (-0.70711d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= -1.06) {
tmp = 0.70711 * ((6.039053782637804 / x) - x);
} else if (x <= 1.15) {
tmp = 1.6316775383 + (x * -2.134856267379707);
} else {
tmp = x * -0.70711;
}
return tmp;
}
def code(x): tmp = 0 if x <= -1.06: tmp = 0.70711 * ((6.039053782637804 / x) - x) elif x <= 1.15: tmp = 1.6316775383 + (x * -2.134856267379707) else: tmp = x * -0.70711 return tmp
function code(x) tmp = 0.0 if (x <= -1.06) tmp = Float64(0.70711 * Float64(Float64(6.039053782637804 / x) - x)); elseif (x <= 1.15) tmp = Float64(1.6316775383 + Float64(x * -2.134856267379707)); else tmp = Float64(x * -0.70711); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= -1.06) tmp = 0.70711 * ((6.039053782637804 / x) - x); elseif (x <= 1.15) tmp = 1.6316775383 + (x * -2.134856267379707); else tmp = x * -0.70711; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, -1.06], N[(0.70711 * N[(N[(6.039053782637804 / x), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 1.15], N[(1.6316775383 + N[(x * -2.134856267379707), $MachinePrecision]), $MachinePrecision], N[(x * -0.70711), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.06:\\
\;\;\;\;0.70711 \cdot \left(\frac{6.039053782637804}{x} - x\right)\\
\mathbf{elif}\;x \leq 1.15:\\
\;\;\;\;1.6316775383 + x \cdot -2.134856267379707\\
\mathbf{else}:\\
\;\;\;\;x \cdot -0.70711\\
\end{array}
\end{array}
if x < -1.0600000000000001Initial program 99.8%
Taylor expanded in x around inf 98.3%
if -1.0600000000000001 < x < 1.1499999999999999Initial program 99.9%
Taylor expanded in x around 0 97.7%
*-commutative97.7%
Simplified97.7%
if 1.1499999999999999 < x Initial program 99.7%
Taylor expanded in x around inf 98.3%
*-commutative98.3%
Simplified98.3%
Final simplification97.9%
(FPCore (x) :precision binary64 (if (or (<= x -1.06) (not (<= x 1.15))) (* x -0.70711) 1.6316775383))
double code(double x) {
double tmp;
if ((x <= -1.06) || !(x <= 1.15)) {
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 <= (-1.06d0)) .or. (.not. (x <= 1.15d0))) 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 <= -1.06) || !(x <= 1.15)) {
tmp = x * -0.70711;
} else {
tmp = 1.6316775383;
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.06) or not (x <= 1.15): tmp = x * -0.70711 else: tmp = 1.6316775383 return tmp
function code(x) tmp = 0.0 if ((x <= -1.06) || !(x <= 1.15)) tmp = Float64(x * -0.70711); else tmp = 1.6316775383; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.06) || ~((x <= 1.15))) tmp = x * -0.70711; else tmp = 1.6316775383; end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.06], N[Not[LessEqual[x, 1.15]], $MachinePrecision]], N[(x * -0.70711), $MachinePrecision], 1.6316775383]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.06 \lor \neg \left(x \leq 1.15\right):\\
\;\;\;\;x \cdot -0.70711\\
\mathbf{else}:\\
\;\;\;\;1.6316775383\\
\end{array}
\end{array}
if x < -1.0600000000000001 or 1.1499999999999999 < x Initial program 99.8%
Taylor expanded in x around inf 97.9%
*-commutative97.9%
Simplified97.9%
if -1.0600000000000001 < x < 1.1499999999999999Initial program 99.9%
Taylor expanded in x around 0 96.6%
Final simplification97.2%
(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}
Initial program 99.9%
Taylor expanded in x around 0 55.1%
Final simplification55.1%
herbie shell --seed 2024053
(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)))