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i0e_7p5_to_9p5_hard

pxfm::bessel::i0e

Function i0e_7p5_to_9p5_hard 

Source 
fn i0e_7p5_to_9p5_hard(x: f64) -> f64
Expand description

Mid-interval [7.5;9.5] generated by Wolfram Mathematica: I0(x)=R(1/x)/sqrt(x)*Exp(x) Polynomial generated by Wolfram Mathematica:

<<FunctionApproximations`
ClearAll["Global`*"]
f[x_]:=Sqrt[x] Exp[-x] BesselI[0,x]
g[z_]:=f[1/z]
{err,approx}=MiniMaxApproximation[g[z],{z,{1/9.5,1/7.5},13,13},WorkingPrecision->120]
poly=Numerator[approx][[1]];
coeffs=CoefficientList[poly,z];
TableForm[Table[Row[{"'",NumberForm[coeffs[[i+1]],{50,50},ExponentFunction->(Null&)],"',"}],{i,0,Length[coeffs]-1}]]
poly=Denominator[approx][[1]];
coeffs=CoefficientList[poly,z];
TableForm[Table[Row[{"'",NumberForm[coeffs[[i+1]],{50,50},ExponentFunction->(Null&)],"',"}],{i,0,Length[coeffs]-1}]]