
(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 6 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
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741) t_0)
-0.284496736)
t_0))
(t_2 (/ (- (- 0.254829592) t_1) (pow (* (pow (exp x) x) t_0) 2.0)))
(t_3 (+ 0.254829592 t_1))
(t_4 (fma t_2 t_3 -1.0))
(t_5 (fma (fabs x) 0.3275911 1.0)))
(/
(- (/ (pow (* t_2 t_3) 2.0) t_4) (pow t_4 -1.0))
(fma
(pow (exp x) (- x))
(/
(+
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_5) -1.453152027) t_5) 1.421413741) t_5)
-0.284496736)
t_5)
0.254829592)
t_5)
1.0))))
double code(double x) {
double t_0 = fma(0.3275911, fabs(x), 1.0);
double t_1 = ((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0;
double t_2 = (-0.254829592 - t_1) / pow((pow(exp(x), x) * t_0), 2.0);
double t_3 = 0.254829592 + t_1;
double t_4 = fma(t_2, t_3, -1.0);
double t_5 = fma(fabs(x), 0.3275911, 1.0);
return ((pow((t_2 * t_3), 2.0) / t_4) - pow(t_4, -1.0)) / fma(pow(exp(x), -x), (((((((((1.061405429 / t_5) + -1.453152027) / t_5) + 1.421413741) / t_5) + -0.284496736) / t_5) + 0.254829592) / t_5), 1.0);
}
function code(x) t_0 = fma(0.3275911, abs(x), 1.0) t_1 = Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) t_2 = Float64(Float64(Float64(-0.254829592) - t_1) / (Float64((exp(x) ^ x) * t_0) ^ 2.0)) t_3 = Float64(0.254829592 + t_1) t_4 = fma(t_2, t_3, -1.0) t_5 = fma(abs(x), 0.3275911, 1.0) return Float64(Float64(Float64((Float64(t_2 * t_3) ^ 2.0) / t_4) - (t_4 ^ -1.0)) / fma((exp(x) ^ Float64(-x)), Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_5) + -1.453152027) / t_5) + 1.421413741) / t_5) + -0.284496736) / t_5) + 0.254829592) / t_5), 1.0)) end
code[x_] := Block[{t$95$0 = N[(0.3275911 * N[Abs[x], $MachinePrecision] + 1.0), $MachinePrecision]}, Block[{t$95$1 = 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]}, Block[{t$95$2 = N[(N[((-0.254829592) - t$95$1), $MachinePrecision] / N[Power[N[(N[Power[N[Exp[x], $MachinePrecision], x], $MachinePrecision] * t$95$0), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(0.254829592 + t$95$1), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$2 * t$95$3 + -1.0), $MachinePrecision]}, Block[{t$95$5 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, N[(N[(N[(N[Power[N[(t$95$2 * t$95$3), $MachinePrecision], 2.0], $MachinePrecision] / t$95$4), $MachinePrecision] - N[Power[t$95$4, -1.0], $MachinePrecision]), $MachinePrecision] / N[(N[Power[N[Exp[x], $MachinePrecision], (-x)], $MachinePrecision] * N[(N[(N[(N[(N[(N[(N[(N[(N[(1.061405429 / t$95$5), $MachinePrecision] + -1.453152027), $MachinePrecision] / t$95$5), $MachinePrecision] + 1.421413741), $MachinePrecision] / t$95$5), $MachinePrecision] + -0.284496736), $MachinePrecision] / t$95$5), $MachinePrecision] + 0.254829592), $MachinePrecision] / t$95$5), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]]]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(0.3275911, \left|x\right|, 1\right)\\
t_1 := \frac{\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0}\\
t_2 := \frac{\left(-0.254829592\right) - t\_1}{{\left({\left(e^{x}\right)}^{x} \cdot t\_0\right)}^{2}}\\
t_3 := 0.254829592 + t\_1\\
t_4 := \mathsf{fma}\left(t\_2, t\_3, -1\right)\\
t_5 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
\frac{\frac{{\left(t\_2 \cdot t\_3\right)}^{2}}{t\_4} - {t\_4}^{-1}}{\mathsf{fma}\left({\left(e^{x}\right)}^{\left(-x\right)}, \frac{\frac{\frac{\frac{\frac{1.061405429}{t\_5} + -1.453152027}{t\_5} + 1.421413741}{t\_5} + -0.284496736}{t\_5} + 0.254829592}{t\_5}, 1\right)}
\end{array}
\end{array}
Initial program 77.4%
Applied rewrites77.4%
lift-pow.f64N/A
unpow2N/A
lift-/.f64N/A
lift-/.f64N/A
Applied rewrites77.4%
Applied rewrites77.4%
Applied rewrites85.2%
Final simplification85.2%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0)))
(-
1.0
(*
(*
(/
(+
(/
(+
(/
(+
(/
(fma
1.061405429
(/
(fma (fabs x) 0.3275911 -1.0)
(fma 0.10731592879921 (* x x) -1.0))
-1.453152027)
t_0)
1.421413741)
t_0)
-0.284496736)
t_0)
0.254829592)
(- 1.0 (* 0.10731592879921 (* x x))))
(- 1.0 (* (fabs x) 0.3275911)))
(exp (* (- x) x))))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
return 1.0 - (((((((((fma(1.061405429, (fma(fabs(x), 0.3275911, -1.0) / fma(0.10731592879921, (x * x), -1.0)), -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / (1.0 - (0.10731592879921 * (x * x)))) * (1.0 - (fabs(x) * 0.3275911))) * exp((-x * 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(fma(1.061405429, Float64(fma(abs(x), 0.3275911, -1.0) / fma(0.10731592879921, Float64(x * x), -1.0)), -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / Float64(1.0 - Float64(0.10731592879921 * Float64(x * x)))) * Float64(1.0 - Float64(abs(x) * 0.3275911))) * exp(Float64(Float64(-x) * 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[(1.061405429 * N[(N[(N[Abs[x], $MachinePrecision] * 0.3275911 + -1.0), $MachinePrecision] / N[(0.10731592879921 * N[(x * x), $MachinePrecision] + -1.0), $MachinePrecision]), $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[(0.10731592879921 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 - N[(N[Abs[x], $MachinePrecision] * 0.3275911), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Exp[N[((-x) * x), $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{\mathsf{fma}\left(1.061405429, \frac{\mathsf{fma}\left(\left|x\right|, 0.3275911, -1\right)}{\mathsf{fma}\left(0.10731592879921, x \cdot x, -1\right)}, -1.453152027\right)}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0} + 0.254829592}{1 - 0.10731592879921 \cdot \left(x \cdot x\right)} \cdot \left(1 - \left|x\right| \cdot 0.3275911\right)\right) \cdot e^{\left(-x\right) \cdot x}
\end{array}
\end{array}
Initial program 77.4%
Applied rewrites77.4%
lift-+.f64N/A
lift-/.f64N/A
lift-fma.f64N/A
lift-*.f64N/A
flip-+N/A
associate-/r/N/A
lower-fma.f64N/A
Applied rewrites77.4%
Applied rewrites77.5%
Final simplification77.5%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma 0.3275911 (fabs x) 1.0)))
(-
1.0
(*
(/
(*
(fma -0.3275911 (fabs x) 1.0)
(+
0.254829592
(/
(+
-0.284496736
(/ (+ 1.421413741 (/ (+ -1.453152027 (/ 1.061405429 t_0)) t_0)) t_0))
t_0)))
(fma -0.10731592879921 (* x x) 1.0))
(exp (* (- x) x))))))
double code(double x) {
double t_0 = fma(0.3275911, fabs(x), 1.0);
return 1.0 - (((fma(-0.3275911, fabs(x), 1.0) * (0.254829592 + ((-0.284496736 + ((1.421413741 + ((-1.453152027 + (1.061405429 / t_0)) / t_0)) / t_0)) / t_0))) / fma(-0.10731592879921, (x * x), 1.0)) * exp((-x * x)));
}
function code(x) t_0 = fma(0.3275911, abs(x), 1.0) return Float64(1.0 - Float64(Float64(Float64(fma(-0.3275911, abs(x), 1.0) * 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))) / fma(-0.10731592879921, Float64(x * x), 1.0)) * exp(Float64(Float64(-x) * x)))) end
code[x_] := Block[{t$95$0 = N[(0.3275911 * N[Abs[x], $MachinePrecision] + 1.0), $MachinePrecision]}, N[(1.0 - N[(N[(N[(N[(-0.3275911 * N[Abs[x], $MachinePrecision] + 1.0), $MachinePrecision] * 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]), $MachinePrecision] / N[(-0.10731592879921 * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision] * N[Exp[N[((-x) * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(0.3275911, \left|x\right|, 1\right)\\
1 - \frac{\mathsf{fma}\left(-0.3275911, \left|x\right|, 1\right) \cdot \left(0.254829592 + \frac{-0.284496736 + \frac{1.421413741 + \frac{-1.453152027 + \frac{1.061405429}{t\_0}}{t\_0}}{t\_0}}{t\_0}\right)}{\mathsf{fma}\left(-0.10731592879921, x \cdot x, 1\right)} \cdot e^{\left(-x\right) \cdot x}
\end{array}
\end{array}
Initial program 77.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6477.4
Applied rewrites77.4%
Applied rewrites77.4%
Final simplification77.4%
(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)
(fma 0.10731592879921 (* x x) -1.0))
(fma (fabs x) 0.3275911 -1.0))
(exp (* (- x) 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) / fma(0.10731592879921, (x * x), -1.0)) * fma(fabs(x), 0.3275911, -1.0)) * exp((-x * 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) / fma(0.10731592879921, Float64(x * x), -1.0)) * fma(abs(x), 0.3275911, -1.0)) * exp(Float64(Float64(-x) * 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[(0.10731592879921 * N[(x * x), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision] * N[(N[Abs[x], $MachinePrecision] * 0.3275911 + -1.0), $MachinePrecision]), $MachinePrecision] * N[Exp[N[((-x) * x), $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}{\mathsf{fma}\left(0.10731592879921, x \cdot x, -1\right)} \cdot \mathsf{fma}\left(\left|x\right|, 0.3275911, -1\right)\right) \cdot e^{\left(-x\right) \cdot x}
\end{array}
\end{array}
Initial program 77.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6477.4
Applied rewrites77.4%
lift-*.f64N/A
lift-fabs.f64N/A
lift-fabs.f64N/A
sqr-absN/A
lift-*.f6477.4
Applied rewrites77.4%
Applied rewrites77.4%
Final simplification77.4%
(FPCore (x)
:precision binary64
(let* ((t_0 (fma (fabs x) 0.3275911 1.0)))
(+
1.0
(*
(*
(/ -1.0 (+ 1.0 (* 0.3275911 (fabs x))))
(+
0.254829592
(/
(+
(/ (+ (/ (+ (/ 1.061405429 t_0) -1.453152027) t_0) 1.421413741) t_0)
-0.284496736)
t_0)))
(exp (* (- x) x))))))
double code(double x) {
double t_0 = fma(fabs(x), 0.3275911, 1.0);
return 1.0 + (((-1.0 / (1.0 + (0.3275911 * fabs(x)))) * (0.254829592 + (((((((1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0))) * exp((-x * x)));
}
function code(x) t_0 = fma(abs(x), 0.3275911, 1.0) return Float64(1.0 + Float64(Float64(Float64(-1.0 / Float64(1.0 + Float64(0.3275911 * abs(x)))) * Float64(0.254829592 + Float64(Float64(Float64(Float64(Float64(Float64(Float64(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0))) * exp(Float64(Float64(-x) * x)))) end
code[x_] := Block[{t$95$0 = N[(N[Abs[x], $MachinePrecision] * 0.3275911 + 1.0), $MachinePrecision]}, N[(1.0 + N[(N[(N[(-1.0 / N[(1.0 + N[(0.3275911 * N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(0.254829592 + 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]), $MachinePrecision]), $MachinePrecision] * N[Exp[N[((-x) * x), $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{-1}{1 + 0.3275911 \cdot \left|x\right|} \cdot \left(0.254829592 + \frac{\frac{\frac{\frac{1.061405429}{t\_0} + -1.453152027}{t\_0} + 1.421413741}{t\_0} + -0.284496736}{t\_0}\right)\right) \cdot e^{\left(-x\right) \cdot x}
\end{array}
\end{array}
Initial program 77.4%
lift-*.f64N/A
lift-/.f64N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites77.4%
lift-*.f64N/A
lift-fabs.f64N/A
lift-fabs.f64N/A
sqr-absN/A
lower-*.f6477.4
Applied rewrites77.4%
Final simplification77.4%
(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)
t_0)
(exp (* (- x) 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) / t_0) * exp((-x * 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(1.061405429 / t_0) + -1.453152027) / t_0) + 1.421413741) / t_0) + -0.284496736) / t_0) + 0.254829592) / t_0) * exp(Float64(Float64(-x) * 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[(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] * N[Exp[N[((-x) * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\left|x\right|, 0.3275911, 1\right)\\
1 - \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} \cdot e^{\left(-x\right) \cdot x}
\end{array}
\end{array}
Initial program 77.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6477.4
Applied rewrites77.4%
lift-*.f64N/A
lift-fabs.f64N/A
lift-fabs.f64N/A
sqr-absN/A
lift-*.f6477.4
Applied rewrites77.4%
Final simplification77.4%
herbie shell --seed 2024302
(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)))))))