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i0e_asympt

pxfm::bessel::i0e

Function i0e_asympt 

Source 
fn i0e_asympt(x: f64) -> f64
Expand description

I0(x)=R(1/x)*Exp(x)/sqrt(x) Generated in Wolfram:

<<FunctionApproximations`
ClearAll["Global`*"]
f[x_]:=Sqrt[x] Exp[-x] BesselI[0,x]
g[z_]:=f[1/z]
{err,approx, err1}=MiniMaxApproximation[g[z],{z,{1/709.3,1/9.5},11,11},WorkingPrecision->120]
poly=Numerator[approx];
coeffs=CoefficientList[poly,z];
TableForm[Table[Row[{"'",NumberForm[coeffs[[i+1]],{50,50},ExponentFunction->(Null&)],"',"}],{i,0,Length[coeffs]-1}]]
poly=Denominator[approx];
coeffs=CoefficientList[poly,z];
TableForm[Table[Row[{"'",NumberForm[coeffs[[i+1]],{50,50},ExponentFunction->(Null&)],"',"}],{i,0,Length[coeffs]-1}]]]