
(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}
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(let* ((t_0 (+ 1.0 (* x_m 0.3275911))) (t_1 (/ 1.0 t_0)))
(if (<= (fabs x_m) 5e-16)
(+ 1e-9 (* x_m 1.128386358070218))
(+
1.0
(*
t_1
(*
(exp (- (* x_m x_m)))
(-
(*
t_1
(-
(*
(+
1.421413741
(+
(/ 1.061405429 (pow (fma 0.3275911 x_m 1.0) 2.0))
(/ -1.453152027 (fma 0.3275911 x_m 1.0))))
(/ -1.0 t_0))
-0.284496736))
0.254829592)))))))x_m = fabs(x);
double code(double x_m) {
double t_0 = 1.0 + (x_m * 0.3275911);
double t_1 = 1.0 / t_0;
double tmp;
if (fabs(x_m) <= 5e-16) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0 + (t_1 * (exp(-(x_m * x_m)) * ((t_1 * (((1.421413741 + ((1.061405429 / pow(fma(0.3275911, x_m, 1.0), 2.0)) + (-1.453152027 / fma(0.3275911, x_m, 1.0)))) * (-1.0 / t_0)) - -0.284496736)) - 0.254829592)));
}
return tmp;
}
x_m = abs(x) function code(x_m) t_0 = Float64(1.0 + Float64(x_m * 0.3275911)) t_1 = Float64(1.0 / t_0) tmp = 0.0 if (abs(x_m) <= 5e-16) tmp = Float64(1e-9 + Float64(x_m * 1.128386358070218)); else tmp = Float64(1.0 + Float64(t_1 * Float64(exp(Float64(-Float64(x_m * x_m))) * Float64(Float64(t_1 * Float64(Float64(Float64(1.421413741 + Float64(Float64(1.061405429 / (fma(0.3275911, x_m, 1.0) ^ 2.0)) + Float64(-1.453152027 / fma(0.3275911, x_m, 1.0)))) * Float64(-1.0 / t_0)) - -0.284496736)) - 0.254829592)))); end return tmp end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := Block[{t$95$0 = N[(1.0 + N[(x$95$m * 0.3275911), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(1.0 / t$95$0), $MachinePrecision]}, If[LessEqual[N[Abs[x$95$m], $MachinePrecision], 5e-16], N[(1e-9 + N[(x$95$m * 1.128386358070218), $MachinePrecision]), $MachinePrecision], N[(1.0 + N[(t$95$1 * N[(N[Exp[(-N[(x$95$m * x$95$m), $MachinePrecision])], $MachinePrecision] * N[(N[(t$95$1 * N[(N[(N[(1.421413741 + N[(N[(1.061405429 / N[Power[N[(0.3275911 * x$95$m + 1.0), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] + N[(-1.453152027 / N[(0.3275911 * x$95$m + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / t$95$0), $MachinePrecision]), $MachinePrecision] - -0.284496736), $MachinePrecision]), $MachinePrecision] - 0.254829592), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
t_0 := 1 + x_m \cdot 0.3275911\\
t_1 := \frac{1}{t_0}\\
\mathbf{if}\;\left|x_m\right| \leq 5 \cdot 10^{-16}:\\
\;\;\;\;10^{-9} + x_m \cdot 1.128386358070218\\
\mathbf{else}:\\
\;\;\;\;1 + t_1 \cdot \left(e^{-x_m \cdot x_m} \cdot \left(t_1 \cdot \left(\left(1.421413741 + \left(\frac{1.061405429}{{\left(\mathsf{fma}\left(0.3275911, x_m, 1\right)\right)}^{2}} + \frac{-1.453152027}{\mathsf{fma}\left(0.3275911, x_m, 1\right)}\right)\right) \cdot \frac{-1}{t_0} - -0.284496736\right) - 0.254829592\right)\right)\\
\end{array}
\end{array}
if (fabs.f64 x) < 5.0000000000000004e-16Initial program 57.7%
Simplified57.7%
Applied egg-rr57.7%
associate-*l/57.7%
associate-/l*57.7%
Simplified57.7%
Taylor expanded in x around 0 99.9%
*-commutative99.9%
Simplified99.9%
if 5.0000000000000004e-16 < (fabs.f64 x) Initial program 99.8%
Simplified99.8%
Taylor expanded in x around 0 99.8%
associate--l+99.8%
sub-neg99.8%
associate-*r/99.8%
metadata-eval99.8%
+-commutative99.8%
fma-def99.8%
unpow199.8%
sqr-pow54.1%
fabs-sqr54.1%
sqr-pow99.2%
unpow199.2%
associate-*r/99.2%
metadata-eval99.2%
distribute-neg-frac99.2%
metadata-eval99.2%
+-commutative99.2%
fma-def99.2%
Simplified99.3%
expm1-log1p-u99.3%
expm1-udef99.3%
log1p-udef99.3%
+-commutative99.3%
add-exp-log99.3%
fma-def99.3%
add-sqr-sqrt54.1%
fabs-sqr54.1%
add-sqr-sqrt99.3%
Applied egg-rr99.3%
fma-udef99.3%
associate--l+99.3%
metadata-eval99.3%
+-rgt-identity99.3%
Simplified99.3%
expm1-log1p-u99.3%
expm1-udef99.3%
log1p-udef99.3%
+-commutative99.3%
add-exp-log99.3%
fma-def99.3%
add-sqr-sqrt54.1%
fabs-sqr54.1%
add-sqr-sqrt99.3%
Applied egg-rr99.2%
fma-udef99.3%
associate--l+99.3%
metadata-eval99.3%
+-rgt-identity99.3%
Simplified99.2%
expm1-log1p-u99.3%
expm1-udef99.3%
log1p-udef99.3%
+-commutative99.3%
add-exp-log99.3%
fma-def99.3%
add-sqr-sqrt54.1%
fabs-sqr54.1%
add-sqr-sqrt99.3%
Applied egg-rr99.2%
fma-udef99.3%
associate--l+99.3%
metadata-eval99.3%
+-rgt-identity99.3%
Simplified99.2%
Final simplification99.5%
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(let* ((t_0 (+ 1.0 (* x_m 0.3275911)))
(t_1 (/ 1.0 (+ 1.0 (* (fabs x_m) 0.3275911)))))
(if (<= x_m 1.25e-6)
(+ 1e-9 (* x_m 1.128386358070218))
(+
1.0
(*
t_1
(*
(exp (- (* x_m x_m)))
(-
(*
t_1
(-
(*
(/ 1.0 t_0)
(-
(* (+ -1.453152027 (/ 1.061405429 t_0)) (/ -1.0 t_0))
1.421413741))
-0.284496736))
0.254829592)))))))x_m = fabs(x);
double code(double x_m) {
double t_0 = 1.0 + (x_m * 0.3275911);
double t_1 = 1.0 / (1.0 + (fabs(x_m) * 0.3275911));
double tmp;
if (x_m <= 1.25e-6) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0 + (t_1 * (exp(-(x_m * x_m)) * ((t_1 * (((1.0 / t_0) * (((-1.453152027 + (1.061405429 / t_0)) * (-1.0 / t_0)) - 1.421413741)) - -0.284496736)) - 0.254829592)));
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: t_0
real(8) :: t_1
real(8) :: tmp
t_0 = 1.0d0 + (x_m * 0.3275911d0)
t_1 = 1.0d0 / (1.0d0 + (abs(x_m) * 0.3275911d0))
if (x_m <= 1.25d-6) then
tmp = 1d-9 + (x_m * 1.128386358070218d0)
else
tmp = 1.0d0 + (t_1 * (exp(-(x_m * x_m)) * ((t_1 * (((1.0d0 / t_0) * ((((-1.453152027d0) + (1.061405429d0 / t_0)) * ((-1.0d0) / t_0)) - 1.421413741d0)) - (-0.284496736d0))) - 0.254829592d0)))
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double t_0 = 1.0 + (x_m * 0.3275911);
double t_1 = 1.0 / (1.0 + (Math.abs(x_m) * 0.3275911));
double tmp;
if (x_m <= 1.25e-6) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0 + (t_1 * (Math.exp(-(x_m * x_m)) * ((t_1 * (((1.0 / t_0) * (((-1.453152027 + (1.061405429 / t_0)) * (-1.0 / t_0)) - 1.421413741)) - -0.284496736)) - 0.254829592)));
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): t_0 = 1.0 + (x_m * 0.3275911) t_1 = 1.0 / (1.0 + (math.fabs(x_m) * 0.3275911)) tmp = 0 if x_m <= 1.25e-6: tmp = 1e-9 + (x_m * 1.128386358070218) else: tmp = 1.0 + (t_1 * (math.exp(-(x_m * x_m)) * ((t_1 * (((1.0 / t_0) * (((-1.453152027 + (1.061405429 / t_0)) * (-1.0 / t_0)) - 1.421413741)) - -0.284496736)) - 0.254829592))) return tmp
x_m = abs(x) function code(x_m) t_0 = Float64(1.0 + Float64(x_m * 0.3275911)) t_1 = Float64(1.0 / Float64(1.0 + Float64(abs(x_m) * 0.3275911))) tmp = 0.0 if (x_m <= 1.25e-6) tmp = Float64(1e-9 + Float64(x_m * 1.128386358070218)); else tmp = Float64(1.0 + Float64(t_1 * Float64(exp(Float64(-Float64(x_m * x_m))) * Float64(Float64(t_1 * Float64(Float64(Float64(1.0 / t_0) * Float64(Float64(Float64(-1.453152027 + Float64(1.061405429 / t_0)) * Float64(-1.0 / t_0)) - 1.421413741)) - -0.284496736)) - 0.254829592)))); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) t_0 = 1.0 + (x_m * 0.3275911); t_1 = 1.0 / (1.0 + (abs(x_m) * 0.3275911)); tmp = 0.0; if (x_m <= 1.25e-6) tmp = 1e-9 + (x_m * 1.128386358070218); else tmp = 1.0 + (t_1 * (exp(-(x_m * x_m)) * ((t_1 * (((1.0 / t_0) * (((-1.453152027 + (1.061405429 / t_0)) * (-1.0 / t_0)) - 1.421413741)) - -0.284496736)) - 0.254829592))); end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := Block[{t$95$0 = N[(1.0 + N[(x$95$m * 0.3275911), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(1.0 / N[(1.0 + N[(N[Abs[x$95$m], $MachinePrecision] * 0.3275911), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x$95$m, 1.25e-6], N[(1e-9 + N[(x$95$m * 1.128386358070218), $MachinePrecision]), $MachinePrecision], N[(1.0 + N[(t$95$1 * N[(N[Exp[(-N[(x$95$m * x$95$m), $MachinePrecision])], $MachinePrecision] * N[(N[(t$95$1 * N[(N[(N[(1.0 / t$95$0), $MachinePrecision] * N[(N[(N[(-1.453152027 + N[(1.061405429 / t$95$0), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / t$95$0), $MachinePrecision]), $MachinePrecision] - 1.421413741), $MachinePrecision]), $MachinePrecision] - -0.284496736), $MachinePrecision]), $MachinePrecision] - 0.254829592), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
t_0 := 1 + x_m \cdot 0.3275911\\
t_1 := \frac{1}{1 + \left|x_m\right| \cdot 0.3275911}\\
\mathbf{if}\;x_m \leq 1.25 \cdot 10^{-6}:\\
\;\;\;\;10^{-9} + x_m \cdot 1.128386358070218\\
\mathbf{else}:\\
\;\;\;\;1 + t_1 \cdot \left(e^{-x_m \cdot x_m} \cdot \left(t_1 \cdot \left(\frac{1}{t_0} \cdot \left(\left(-1.453152027 + \frac{1.061405429}{t_0}\right) \cdot \frac{-1}{t_0} - 1.421413741\right) - -0.284496736\right) - 0.254829592\right)\right)\\
\end{array}
\end{array}
if x < 1.2500000000000001e-6Initial program 70.1%
Simplified70.1%
Applied egg-rr41.6%
associate-*l/41.6%
associate-/l*41.6%
Simplified41.6%
Taylor expanded in x around 0 70.8%
*-commutative70.8%
Simplified70.8%
if 1.2500000000000001e-6 < x Initial program 100.0%
Simplified100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
log1p-udef100.0%
+-commutative100.0%
add-exp-log100.0%
fma-def100.0%
add-sqr-sqrt100.0%
fabs-sqr100.0%
add-sqr-sqrt100.0%
Applied egg-rr100.0%
fma-udef100.0%
associate--l+100.0%
metadata-eval100.0%
+-rgt-identity100.0%
Simplified100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
log1p-udef100.0%
+-commutative100.0%
add-exp-log100.0%
fma-def100.0%
add-sqr-sqrt100.0%
fabs-sqr100.0%
add-sqr-sqrt100.0%
Applied egg-rr100.0%
fma-udef100.0%
associate--l+100.0%
metadata-eval100.0%
+-rgt-identity100.0%
Simplified100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
log1p-udef100.0%
+-commutative100.0%
add-exp-log100.0%
fma-def100.0%
add-sqr-sqrt100.0%
fabs-sqr100.0%
add-sqr-sqrt100.0%
Applied egg-rr100.0%
fma-udef100.0%
associate--l+100.0%
metadata-eval100.0%
+-rgt-identity100.0%
Simplified100.0%
Final simplification78.3%
x_m = (fabs.f64 x)
(FPCore (x_m)
:precision binary64
(let* ((t_0 (+ 1.0 (* x_m 0.3275911))))
(if (<= x_m 0.5)
(+ 1e-9 (* x_m 1.128386358070218))
(+
1.0
(*
(/ 1.0 (+ 1.0 (* (fabs x_m) 0.3275911)))
(*
(exp (- (* x_m x_m)))
(-
(* (/ 1.0 t_0) (- (* 1.029667143 (/ -1.0 t_0)) -0.284496736))
0.254829592)))))))x_m = fabs(x);
double code(double x_m) {
double t_0 = 1.0 + (x_m * 0.3275911);
double tmp;
if (x_m <= 0.5) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0 + ((1.0 / (1.0 + (fabs(x_m) * 0.3275911))) * (exp(-(x_m * x_m)) * (((1.0 / t_0) * ((1.029667143 * (-1.0 / t_0)) - -0.284496736)) - 0.254829592)));
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: t_0
real(8) :: tmp
t_0 = 1.0d0 + (x_m * 0.3275911d0)
if (x_m <= 0.5d0) then
tmp = 1d-9 + (x_m * 1.128386358070218d0)
else
tmp = 1.0d0 + ((1.0d0 / (1.0d0 + (abs(x_m) * 0.3275911d0))) * (exp(-(x_m * x_m)) * (((1.0d0 / t_0) * ((1.029667143d0 * ((-1.0d0) / t_0)) - (-0.284496736d0))) - 0.254829592d0)))
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double t_0 = 1.0 + (x_m * 0.3275911);
double tmp;
if (x_m <= 0.5) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0 + ((1.0 / (1.0 + (Math.abs(x_m) * 0.3275911))) * (Math.exp(-(x_m * x_m)) * (((1.0 / t_0) * ((1.029667143 * (-1.0 / t_0)) - -0.284496736)) - 0.254829592)));
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): t_0 = 1.0 + (x_m * 0.3275911) tmp = 0 if x_m <= 0.5: tmp = 1e-9 + (x_m * 1.128386358070218) else: tmp = 1.0 + ((1.0 / (1.0 + (math.fabs(x_m) * 0.3275911))) * (math.exp(-(x_m * x_m)) * (((1.0 / t_0) * ((1.029667143 * (-1.0 / t_0)) - -0.284496736)) - 0.254829592))) return tmp
x_m = abs(x) function code(x_m) t_0 = Float64(1.0 + Float64(x_m * 0.3275911)) tmp = 0.0 if (x_m <= 0.5) tmp = Float64(1e-9 + Float64(x_m * 1.128386358070218)); else tmp = Float64(1.0 + Float64(Float64(1.0 / Float64(1.0 + Float64(abs(x_m) * 0.3275911))) * Float64(exp(Float64(-Float64(x_m * x_m))) * Float64(Float64(Float64(1.0 / t_0) * Float64(Float64(1.029667143 * Float64(-1.0 / t_0)) - -0.284496736)) - 0.254829592)))); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) t_0 = 1.0 + (x_m * 0.3275911); tmp = 0.0; if (x_m <= 0.5) tmp = 1e-9 + (x_m * 1.128386358070218); else tmp = 1.0 + ((1.0 / (1.0 + (abs(x_m) * 0.3275911))) * (exp(-(x_m * x_m)) * (((1.0 / t_0) * ((1.029667143 * (-1.0 / t_0)) - -0.284496736)) - 0.254829592))); end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision]
code[x$95$m_] := Block[{t$95$0 = N[(1.0 + N[(x$95$m * 0.3275911), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x$95$m, 0.5], N[(1e-9 + N[(x$95$m * 1.128386358070218), $MachinePrecision]), $MachinePrecision], N[(1.0 + N[(N[(1.0 / N[(1.0 + N[(N[Abs[x$95$m], $MachinePrecision] * 0.3275911), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Exp[(-N[(x$95$m * x$95$m), $MachinePrecision])], $MachinePrecision] * N[(N[(N[(1.0 / t$95$0), $MachinePrecision] * N[(N[(1.029667143 * N[(-1.0 / t$95$0), $MachinePrecision]), $MachinePrecision] - -0.284496736), $MachinePrecision]), $MachinePrecision] - 0.254829592), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
t_0 := 1 + x_m \cdot 0.3275911\\
\mathbf{if}\;x_m \leq 0.5:\\
\;\;\;\;10^{-9} + x_m \cdot 1.128386358070218\\
\mathbf{else}:\\
\;\;\;\;1 + \frac{1}{1 + \left|x_m\right| \cdot 0.3275911} \cdot \left(e^{-x_m \cdot x_m} \cdot \left(\frac{1}{t_0} \cdot \left(1.029667143 \cdot \frac{-1}{t_0} - -0.284496736\right) - 0.254829592\right)\right)\\
\end{array}
\end{array}
if x < 0.5Initial program 70.1%
Simplified70.1%
Applied egg-rr41.6%
associate-*l/41.6%
associate-/l*41.6%
Simplified41.6%
Taylor expanded in x around 0 70.8%
*-commutative70.8%
Simplified70.8%
if 0.5 < x Initial program 100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
associate--l+100.0%
sub-neg100.0%
associate-*r/100.0%
metadata-eval100.0%
+-commutative100.0%
fma-def100.0%
unpow1100.0%
sqr-pow100.0%
fabs-sqr100.0%
sqr-pow100.0%
unpow1100.0%
associate-*r/100.0%
metadata-eval100.0%
distribute-neg-frac100.0%
metadata-eval100.0%
+-commutative100.0%
fma-def100.0%
Simplified100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
log1p-udef100.0%
+-commutative100.0%
add-exp-log100.0%
fma-def100.0%
add-sqr-sqrt100.0%
fabs-sqr100.0%
add-sqr-sqrt100.0%
Applied egg-rr100.0%
fma-udef100.0%
associate--l+100.0%
metadata-eval100.0%
+-rgt-identity100.0%
Simplified100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
log1p-udef100.0%
+-commutative100.0%
add-exp-log100.0%
fma-def100.0%
add-sqr-sqrt100.0%
fabs-sqr100.0%
add-sqr-sqrt100.0%
Applied egg-rr100.0%
fma-udef100.0%
associate--l+100.0%
metadata-eval100.0%
+-rgt-identity100.0%
Simplified100.0%
Taylor expanded in x around 0 99.4%
Final simplification78.1%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 0.88) (+ 1e-9 (* x_m 1.128386358070218)) 1.0))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 0.88) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 0.88d0) then
tmp = 1d-9 + (x_m * 1.128386358070218d0)
else
tmp = 1.0d0
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 0.88) {
tmp = 1e-9 + (x_m * 1.128386358070218);
} else {
tmp = 1.0;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 0.88: tmp = 1e-9 + (x_m * 1.128386358070218) else: tmp = 1.0 return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 0.88) tmp = Float64(1e-9 + Float64(x_m * 1.128386358070218)); else tmp = 1.0; end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 0.88) tmp = 1e-9 + (x_m * 1.128386358070218); else tmp = 1.0; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 0.88], N[(1e-9 + N[(x$95$m * 1.128386358070218), $MachinePrecision]), $MachinePrecision], 1.0]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x_m \leq 0.88:\\
\;\;\;\;10^{-9} + x_m \cdot 1.128386358070218\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < 0.880000000000000004Initial program 70.1%
Simplified70.1%
Applied egg-rr41.6%
associate-*l/41.6%
associate-/l*41.6%
Simplified41.6%
Taylor expanded in x around 0 70.8%
*-commutative70.8%
Simplified70.8%
if 0.880000000000000004 < x Initial program 100.0%
Simplified100.0%
Applied egg-rr0.0%
associate-*l/0.0%
associate-/l*0.0%
Simplified0.0%
Taylor expanded in x around inf 99.3%
Final simplification78.1%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 2.8e-5) 1e-9 1.0))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 2.8e-5) {
tmp = 1e-9;
} else {
tmp = 1.0;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 2.8d-5) then
tmp = 1d-9
else
tmp = 1.0d0
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 2.8e-5) {
tmp = 1e-9;
} else {
tmp = 1.0;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 2.8e-5: tmp = 1e-9 else: tmp = 1.0 return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 2.8e-5) tmp = 1e-9; else tmp = 1.0; end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 2.8e-5) tmp = 1e-9; else tmp = 1.0; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 2.8e-5], 1e-9, 1.0]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x_m \leq 2.8 \cdot 10^{-5}:\\
\;\;\;\;10^{-9}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < 2.79999999999999996e-5Initial program 70.1%
Simplified70.1%
Applied egg-rr41.6%
associate-*l/41.6%
associate-/l*41.6%
Simplified41.6%
Taylor expanded in x around 0 73.2%
if 2.79999999999999996e-5 < x Initial program 100.0%
Simplified100.0%
Applied egg-rr0.0%
associate-*l/0.0%
associate-/l*0.0%
Simplified0.0%
Taylor expanded in x around inf 99.3%
Final simplification79.9%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 1e-9)
x_m = fabs(x);
double code(double x_m) {
return 1e-9;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = 1d-9
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return 1e-9;
}
x_m = math.fabs(x) def code(x_m): return 1e-9
x_m = abs(x) function code(x_m) return 1e-9 end
x_m = abs(x); function tmp = code(x_m) tmp = 1e-9; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := 1e-9
\begin{array}{l}
x_m = \left|x\right|
\\
10^{-9}
\end{array}
Initial program 77.8%
Simplified77.8%
Applied egg-rr30.9%
associate-*l/30.9%
associate-/l*30.9%
Simplified30.9%
Taylor expanded in x around 0 57.2%
Final simplification57.2%
herbie shell --seed 2023339
(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)))))))