
(FPCore (x)
:precision binary64
(let* ((t_0 (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x))))))
(-
1.0
(*
(*
t_0
(+
0.254829592
(*
t_0
(+
-0.284496736
(*
t_0
(+ 1.421413741 (* t_0 (+ -1.453152027 (* t_0 1.061405429)))))))))
(exp (- (* (fabs x) (fabs x))))))))
double code(double x) {
double t_0 = 1.0 / (1.0 + (0.3275911 * fabs(x)));
return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * exp(-(fabs(x) * fabs(x))));
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = 1.0d0 / (1.0d0 + (0.3275911d0 * abs(x)))
code = 1.0d0 - ((t_0 * (0.254829592d0 + (t_0 * ((-0.284496736d0) + (t_0 * (1.421413741d0 + (t_0 * ((-1.453152027d0) + (t_0 * 1.061405429d0))))))))) * exp(-(abs(x) * abs(x))))
end function
public static double code(double x) {
double t_0 = 1.0 / (1.0 + (0.3275911 * Math.abs(x)));
return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * Math.exp(-(Math.abs(x) * Math.abs(x))));
}
def code(x): t_0 = 1.0 / (1.0 + (0.3275911 * math.fabs(x))) return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * math.exp(-(math.fabs(x) * math.fabs(x))))
function code(x) t_0 = Float64(1.0 / Float64(1.0 + Float64(0.3275911 * abs(x)))) return Float64(1.0 - Float64(Float64(t_0 * Float64(0.254829592 + Float64(t_0 * Float64(-0.284496736 + Float64(t_0 * Float64(1.421413741 + Float64(t_0 * Float64(-1.453152027 + Float64(t_0 * 1.061405429))))))))) * exp(Float64(-Float64(abs(x) * abs(x)))))) end
function tmp = code(x) t_0 = 1.0 / (1.0 + (0.3275911 * abs(x))); tmp = 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * exp(-(abs(x) * abs(x)))); end
code[x_] := Block[{t$95$0 = N[(1.0 / N[(1.0 + N[(0.3275911 * N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(1.0 - N[(N[(t$95$0 * N[(0.254829592 + N[(t$95$0 * N[(-0.284496736 + N[(t$95$0 * N[(1.421413741 + N[(t$95$0 * N[(-1.453152027 + N[(t$95$0 * 1.061405429), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Exp[(-N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision])], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{1 + 0.3275911 \cdot \left|x\right|}\\
1 - \left(t\_0 \cdot \left(0.254829592 + t\_0 \cdot \left(-0.284496736 + t\_0 \cdot \left(1.421413741 + t\_0 \cdot \left(-1.453152027 + t\_0 \cdot 1.061405429\right)\right)\right)\right)\right) \cdot e^{-\left|x\right| \cdot \left|x\right|}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x)
:precision binary64
(let* ((t_0 (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x))))))
(-
1.0
(*
(*
t_0
(+
0.254829592
(*
t_0
(+
-0.284496736
(*
t_0
(+ 1.421413741 (* t_0 (+ -1.453152027 (* t_0 1.061405429)))))))))
(exp (- (* (fabs x) (fabs x))))))))
double code(double x) {
double t_0 = 1.0 / (1.0 + (0.3275911 * fabs(x)));
return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * exp(-(fabs(x) * fabs(x))));
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = 1.0d0 / (1.0d0 + (0.3275911d0 * abs(x)))
code = 1.0d0 - ((t_0 * (0.254829592d0 + (t_0 * ((-0.284496736d0) + (t_0 * (1.421413741d0 + (t_0 * ((-1.453152027d0) + (t_0 * 1.061405429d0))))))))) * exp(-(abs(x) * abs(x))))
end function
public static double code(double x) {
double t_0 = 1.0 / (1.0 + (0.3275911 * Math.abs(x)));
return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * Math.exp(-(Math.abs(x) * Math.abs(x))));
}
def code(x): t_0 = 1.0 / (1.0 + (0.3275911 * math.fabs(x))) return 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * math.exp(-(math.fabs(x) * math.fabs(x))))
function code(x) t_0 = Float64(1.0 / Float64(1.0 + Float64(0.3275911 * abs(x)))) return Float64(1.0 - Float64(Float64(t_0 * Float64(0.254829592 + Float64(t_0 * Float64(-0.284496736 + Float64(t_0 * Float64(1.421413741 + Float64(t_0 * Float64(-1.453152027 + Float64(t_0 * 1.061405429))))))))) * exp(Float64(-Float64(abs(x) * abs(x)))))) end
function tmp = code(x) t_0 = 1.0 / (1.0 + (0.3275911 * abs(x))); tmp = 1.0 - ((t_0 * (0.254829592 + (t_0 * (-0.284496736 + (t_0 * (1.421413741 + (t_0 * (-1.453152027 + (t_0 * 1.061405429))))))))) * exp(-(abs(x) * abs(x)))); end
code[x_] := Block[{t$95$0 = N[(1.0 / N[(1.0 + N[(0.3275911 * N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(1.0 - N[(N[(t$95$0 * N[(0.254829592 + N[(t$95$0 * N[(-0.284496736 + N[(t$95$0 * N[(1.421413741 + N[(t$95$0 * N[(-1.453152027 + N[(t$95$0 * 1.061405429), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Exp[(-N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision])], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{1 + 0.3275911 \cdot \left|x\right|}\\
1 - \left(t\_0 \cdot \left(0.254829592 + t\_0 \cdot \left(-0.284496736 + t\_0 \cdot \left(1.421413741 + t\_0 \cdot \left(-1.453152027 + t\_0 \cdot 1.061405429\right)\right)\right)\right)\right) \cdot e^{-\left|x\right| \cdot \left|x\right|}
\end{array}
\end{array}
(FPCore (x)
:precision binary64
(let* ((t_0 (fma 0.3275911 (fabs x) 1.0))
(t_1 (pow (exp x) x))
(t_2 (fma (fabs x) 0.3275911 1.0))
(t_3
(/
(+
0.254829592
(/
(+
-0.284496736
(/
(+ 1.421413741 (/ (+ -1.453152027 (/ 1.061405429 t_0)) t_0))
t_0))
t_0))
(* t_1 t_0)))
(t_4 (pow t_3 2.0)))
(*
(/
-1.0
(-
-1.0
(/
(+
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_2) -1.453152027) t_2) 1.421413741) t_2)
-0.284496736)
t_2)
0.254829592)
(* t_2 t_1))))
(- (/ -1.0 (- -1.0 t_4)) (/ (pow t_3 4.0) (- t_4 -1.0))))))
double code(double x) {
double t_0 = fma(0.3275911, fabs(x), 1.0);
double t_1 = pow(exp(x), x);
double t_2 = fma(fabs(x), 0.3275911, 1.0);
double t_3 = (0.254829592 + ((-0.284496736 + ((1.421413741 + ((-1.453152027 + (1.061405429 / t_0)) / t_0)) / t_0)) / t_0)) / (t_1 * t_0);
double t_4 = pow(t_3, 2.0);
return (-1.0 / (-1.0 - (((((((((1.061405429 / t_2) + -1.453152027) / t_2) + 1.421413741) / t_2) + -0.284496736) / t_2) + 0.254829592) / (t_2 * t_1)))) * ((-1.0 / (-1.0 - t_4)) - (pow(t_3, 4.0) / (t_4 - -1.0)));
}
function code(x) t_0 = fma(0.3275911, abs(x), 1.0) t_1 = exp(x) ^ x t_2 = fma(abs(x), 0.3275911, 1.0) t_3 = Float64(Float64(0.254829592 + Float64(Float64(-0.284496736 + Float64(Float64(1.421413741 + Float64(Float64(-1.453152027 + Float64(1.061405429 / t_0)) / t_0)) / t_0)) / t_0)) / Float64(t_1 * t_0)) t_4 = t_3 ^ 2.0 return Float64(Float64(-1.0 / Float64(-1.0 - Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_2) + -1.453152027) / t_2) + 1.421413741) / t_2) + -0.284496736) / t_2) + 0.254829592) / Float64(t_2 * t_1)))) * Float64(Float64(-1.0 / Float64(-1.0 - t_4)) - Float64((t_3 ^ 4.0) / Float64(t_4 - -1.0)))) end
code[x_] := Block[{t$95$0 = N[(0.3275911 * N[Abs[x], $MachinePrecision] + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Exp[x], $MachinePrecision], x], $MachinePrecision]}, Block[{t$95$2 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, Block[{t$95$3 = N[(N[(0.254829592 + N[(N[(-0.284496736 + N[(N[(1.421413741 + N[(N[(-1.453152027 + N[(1.061405429 / t$95$0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / N[(t$95$1 * t$95$0), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[Power[t$95$3, 2.0], $MachinePrecision]}, N[(N[(-1.0 / N[(-1.0 - N[(N[(N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$2), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$2), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$2), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$2), $MachinePrecision] + 0.254829592), $MachinePrecision] / N[(t$95$2 * t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(-1.0 / N[(-1.0 - t$95$4), $MachinePrecision]), $MachinePrecision] - N[(N[Power[t$95$3, 4.0], $MachinePrecision] / N[(t$95$4 - -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(0.3275911, \left|x\right|, 1\right)\\
t_1 := {\left(e^{x}\right)}^{x}\\
t_2 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
t_3 := \frac{0.254829592 + \frac{-0.284496736 + \frac{1.421413741 + \frac{-1.453152027 + \frac{1.061405429}{t\_0}}{t\_0}}{t\_0}}{t\_0}}{t\_1 \cdot t\_0}\\
t_4 := {t\_3}^{2}\\
\frac{-1}{-1 - \frac{\frac{\frac{\frac{\frac{1.061405429}{t\_2} + -1.453152027}{t\_2} + 1.421413741}{t\_2} + -0.284496736}{t\_2} + 0.254829592}{t\_2 \cdot t\_1}} \cdot \left(\frac{-1}{-1 - t\_4} - \frac{{t\_3}^{4}}{t\_4 - -1}\right)
\end{array}
\end{array}
Initial program 80.3%
Applied rewrites80.3%
Applied rewrites87.2%
Applied rewrites87.2%
Final simplification87.2%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0))
(t_1
(+
(/
(+
(/
(+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741)
t_0)
-0.284496736)
t_0)
0.254829592))
(t_2 (* t_0 (pow (exp x) x))))
(/
(- 1.0 (/ 1.0 (/ (pow t_2 3.0) (pow t_1 3.0))))
(fma (/ t_1 t_2) (fma (pow (exp x) (- x)) (/ t_1 t_0) 1.0) 1.0))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
double t_1 = (((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592;
double t_2 = t_0 * pow(exp(x), x);
return (1.0 - (1.0 / (pow(t_2, 3.0) / pow(t_1, 3.0)))) / fma((t_1 / t_2), fma(pow(exp(x), -x), (t_1 / t_0), 1.0), 1.0);
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) t_1 = Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) t_2 = Float64(t_0 * (exp(x) ^ x)) return Float64(Float64(1.0 - Float64(1.0 / Float64((t_2 ^ 3.0) / (t_1 ^ 3.0)))) / fma(Float64(t_1 / t_2), fma((exp(x) ^ Float64(-x)), Float64(t_1 / t_0), 1.0), 1.0)) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$0), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$0), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$0), $MachinePrecision] + 0.254829592), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$0 * N[Power[N[Exp[x], $MachinePrecision], x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - N[(1.0 / N[(N[Power[t$95$2, 3.0], $MachinePrecision] / N[Power[t$95$1, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(t$95$1 / t$95$2), $MachinePrecision] * N[(N[Power[N[Exp[x], $MachinePrecision], (-x)], $MachinePrecision] * N[(t$95$1 / t$95$0), $MachinePrecision] + 1.0), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
t_1 := \frac{\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0} + 0.254829592\\
t_2 := t\_0 \cdot {\left(e^{x}\right)}^{x}\\
\frac{1 - \frac{1}{\frac{{t\_2}^{3}}{{t\_1}^{3}}}}{\mathsf{fma}\left(\frac{t\_1}{t\_2}, \mathsf{fma}\left({\left(e^{x}\right)}^{\left(-x\right)}, \frac{t\_1}{t\_0}, 1\right), 1\right)}
\end{array}
\end{array}
Initial program 80.3%
Applied rewrites80.3%
Applied rewrites81.4%
Final simplification81.4%
(FPCore (x)
:precision binary64
(let* ((t_0 (* (fabs x) 0.3275911)) (t_1 (- -1.0 t_0)) (t_2 (/ 1.0 t_1)))
(-
1.0
(*
(exp (* (- (fabs x)) (fabs x)))
(*
(-
(*
(-
(*
t_2
(-
1.421413741
(*
t_2
(fma
(/ 1.061405429 (- 1.0 (* (* x x) 0.10731592879921)))
(- 1.0 t_0)
-1.453152027))))
-0.284496736)
(/ -1.0 t_1))
0.254829592)
t_2)))))
double code(double x) {
double t_0 = fabs(x) * 0.3275911;
double t_1 = -1.0 - t_0;
double t_2 = 1.0 / t_1;
return 1.0 - (exp((-fabs(x) * fabs(x))) * (((((t_2 * (1.421413741 - (t_2 * fma((1.061405429 / (1.0 - ((x * x) * 0.10731592879921))), (1.0 - t_0), -1.453152027)))) - -0.284496736) * (-1.0 / t_1)) - 0.254829592) * t_2));
}
function code(x) t_0 = Float64(abs(x) * 0.3275911) t_1 = Float64(-1.0 - t_0) t_2 = Float64(1.0 / t_1) return Float64(1.0 - Float64(exp(Float64(Float64(-abs(x)) * abs(x))) * Float64(Float64(Float64(Float64(Float64(t_2 * Float64(1.421413741 - Float64(t_2 * fma(Float64(1.061405429 / Float64(1.0 - Float64(Float64(x * x) * 0.10731592879921))), Float64(1.0 - t_0), -1.453152027)))) - -0.284496736) * Float64(-1.0 / t_1)) - 0.254829592) * t_2))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911), $MachinePrecision]}, Block[{t$95$1 = N[(-1.0 - t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / t$95$1), $MachinePrecision]}, N[(1.0 - N[(N[Exp[N[((-N[Abs[x], $MachinePrecision]) * N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(N[(N[(t$95$2 * N[(1.421413741 - N[(t$95$2 * N[(N[(1.061405429 / N[(1.0 - N[(N[(x * x), $MachinePrecision] * 0.10731592879921), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 - t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - -0.284496736), $MachinePrecision] * N[(-1.0 / t$95$1), $MachinePrecision]), $MachinePrecision] - 0.254829592), $MachinePrecision] * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left|x\right| \cdot 0.3275911\\
t_1 := -1 - t\_0\\
t_2 := \frac{1}{t\_1}\\
1 - e^{\left(-\left|x\right|\right) \cdot \left|x\right|} \cdot \left(\left(\left(t\_2 \cdot \left(1.421413741 - t\_2 \cdot \mathsf{fma}\left(\frac{1.061405429}{1 - \left(x \cdot x\right) \cdot 0.10731592879921}, 1 - t\_0, -1.453152027\right)\right) - -0.284496736\right) \cdot \frac{-1}{t\_1} - 0.254829592\right) \cdot t\_2\right)
\end{array}
\end{array}
Initial program 80.3%
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lift-/.f64N/A
associate-*l/N/A
metadata-evalN/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
lower-fma.f64N/A
Applied rewrites80.4%
Final simplification80.4%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0))
(t_1 (* (fabs x) 0.3275911))
(t_2 (/ 1.0 (- -1.0 t_1))))
(-
1.0
(*
(*
(-
(*
t_2
(+
(*
(/
(+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741)
(- 1.0 (* (* x x) 0.10731592879921)))
(- 1.0 t_1))
-0.284496736))
0.254829592)
t_2)
(exp (* (- (fabs x)) (fabs x)))))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
double t_1 = fabs(x) * 0.3275911;
double t_2 = 1.0 / (-1.0 - t_1);
return 1.0 - ((((t_2 * (((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / (1.0 - ((x * x) * 0.10731592879921))) * (1.0 - t_1)) + -0.284496736)) - 0.254829592) * t_2) * exp((-fabs(x) * fabs(x))));
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) t_1 = Float64(abs(x) * 0.3275911) t_2 = Float64(1.0 / Float64(-1.0 - t_1)) return Float64(1.0 - Float64(Float64(Float64(Float64(t_2 * Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / Float64(1.0 - Float64(Float64(x * x) * 0.10731592879921))) * Float64(1.0 - t_1)) + -0.284496736)) - 0.254829592) * t_2) * exp(Float64(Float64(-abs(x)) * abs(x))))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[Abs[x], $MachinePrecision] * 0.3275911), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / N[(-1.0 - t$95$1), $MachinePrecision]), $MachinePrecision]}, N[(1.0 - N[(N[(N[(N[(t$95$2 * N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$0), $MachinePrecision] + 1.421413741), $MachinePrecision] / N[(1.0 - N[(N[(x * x), $MachinePrecision] * 0.10731592879921), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 - t$95$1), $MachinePrecision]), $MachinePrecision] + -0.284496736), $MachinePrecision]), $MachinePrecision] - 0.254829592), $MachinePrecision] * t$95$2), $MachinePrecision] * N[Exp[N[((-N[Abs[x], $MachinePrecision]) * N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
t_1 := \left|x\right| \cdot 0.3275911\\
t_2 := \frac{1}{-1 - t\_1}\\
1 - \left(\left(t\_2 \cdot \left(\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{1 - \left(x \cdot x\right) \cdot 0.10731592879921} \cdot \left(1 - t\_1\right) + -0.284496736\right) - 0.254829592\right) \cdot t\_2\right) \cdot e^{\left(-\left|x\right|\right) \cdot \left|x\right|}
\end{array}
\end{array}
Initial program 80.3%
lift-*.f64N/A
lift-/.f64N/A
associate-*l/N/A
lift-+.f64N/A
flip-+N/A
associate-/r/N/A
lower-*.f64N/A
Applied rewrites80.3%
Final simplification80.3%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0)))
(-
1.0
(*
(*
(/
(+
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741) t_0)
-0.284496736)
t_0)
0.254829592)
(- 1.0 (* (* x x) 0.10731592879921)))
(- 1.0 (* (fabs x) 0.3275911)))
(exp (* (- (fabs x)) (fabs x)))))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
return 1.0 - (((((((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / (1.0 - ((x * x) * 0.10731592879921))) * (1.0 - (fabs(x) * 0.3275911))) * exp((-fabs(x) * fabs(x))));
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) return Float64(1.0 - Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / Float64(1.0 - Float64(Float64(x * x) * 0.10731592879921))) * Float64(1.0 - Float64(abs(x) * 0.3275911))) * exp(Float64(Float64(-abs(x)) * abs(x))))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, N[(1.0 - N[(N[(N[(N[(N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$0), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$0), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$0), $MachinePrecision] + 0.254829592), $MachinePrecision] / N[(1.0 - N[(N[(x * x), $MachinePrecision] * 0.10731592879921), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 - N[(N[Abs[x], $MachinePrecision] * 0.3275911), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Exp[N[((-N[Abs[x], $MachinePrecision]) * N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
1 - \left(\frac{\frac{\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0} + 0.254829592}{1 - \left(x \cdot x\right) \cdot 0.10731592879921} \cdot \left(1 - \left|x\right| \cdot 0.3275911\right)\right) \cdot e^{\left(-\left|x\right|\right) \cdot \left|x\right|}
\end{array}
\end{array}
Initial program 80.3%
Applied rewrites80.3%
Final simplification80.3%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0)))
(-
1.0
(*
(exp (* (- x) x))
(/
(+
(/
(+
(/
(+ (/ (fma -1.061405429 (/ -1.0 t_0) -1.453152027) t_0) 1.421413741)
t_0)
-0.284496736)
t_0)
0.254829592)
t_0)))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
return 1.0 - (exp((-x * x)) * (((((((fma(-1.061405429, (-1.0 / t_0), -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / t_0));
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) return Float64(1.0 - Float64(exp(Float64(Float64(-x) * x)) * Float64(Float64(Float64(Float64(Float64(Float64(Float64(fma(-1.061405429, Float64(-1.0 / t_0), -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / t_0))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, N[(1.0 - N[(N[Exp[N[((-x) * x), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(N[(N[(N[(N[(N[(-1.061405429 * N[(-1.0 / t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$0), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$0), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$0), $MachinePrecision] + 0.254829592), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
1 - e^{\left(-x\right) \cdot x} \cdot \frac{\frac{\frac{\frac{\mathsf{fma}\left(-1.061405429, \frac{-1}{t\_0}, -1.453152027\right)}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0} + 0.254829592}{t\_0}
\end{array}
\end{array}
Initial program 80.3%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6480.3
Applied rewrites80.3%
lift-*.f64N/A
lift-fabs.f64N/A
lift-fabs.f64N/A
sqr-absN/A
lift-*.f6480.3
Applied rewrites80.3%
lift-+.f64N/A
lift-/.f64N/A
frac-2negN/A
lift-fma.f64N/A
*-commutativeN/A
lift-fma.f64N/A
div-invN/A
metadata-evalN/A
frac-2negN/A
lift-/.f64N/A
lower-fma.f64N/A
metadata-eval80.3
lift-fma.f64N/A
*-commutativeN/A
lift-fma.f6480.3
Applied rewrites80.3%
Final simplification80.3%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0)))
(-
1.0
(*
(exp (* (- x) x))
(/
(+
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741) t_0)
-0.284496736)
t_0)
0.254829592)
t_0)))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
return 1.0 - (exp((-x * x)) * (((((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / t_0));
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) return Float64(1.0 - Float64(exp(Float64(Float64(-x) * x)) * Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / t_0))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, N[(1.0 - N[(N[Exp[N[((-x) * x), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$0), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$0), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$0), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$0), $MachinePrecision] + 0.254829592), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
1 - e^{\left(-x\right) \cdot x} \cdot \frac{\frac{\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0} + 0.254829592}{t\_0}
\end{array}
\end{array}
Initial program 80.3%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6480.3
Applied rewrites80.3%
lift-*.f64N/A
lift-fabs.f64N/A
lift-fabs.f64N/A
sqr-absN/A
lift-*.f6480.3
Applied rewrites80.3%
Final simplification80.3%
herbie shell --seed 2024243
(FPCore (x)
:name "Jmat.Real.erf"
:precision binary64
(- 1.0 (* (* (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x)))) (+ 0.254829592 (* (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x)))) (+ -0.284496736 (* (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x)))) (+ 1.421413741 (* (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x)))) (+ -1.453152027 (* (/ 1.0 (+ 1.0 (* 0.3275911 (fabs x)))) 1.061405429))))))))) (exp (- (* (fabs x) (fabs x)))))))