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A slight problem I've had with a function defined by a numerical integral. The definition is

f[q_,c_,n_]:=NIntegrate[\[Beta]*BesselJ[0,q*\[Beta]]*(E^(I*c*((\[Beta] BesselK[1,\[Beta]] HypergeometricPFQ[{1},{1+n/2,1+n/2},\[Beta]^2/4]+n BesselK[0,\[Beta]] HypergeometricPFQ[{1},{1+n/2,n/2},\[Beta]^2/4])/n^2))-1),{\[Beta],0,Infinity},Method->"ExtrapolatingOscillatory"]

I can evaluate this at q=0 without problems. But I've been filling out tables of values with the intent of constructing interpolating functions, and getting this error message:

Power::infy: Infinite expression 1/0. encountered. >>

\[Infinity]::indet:Indeterminate expression ComplexInfinity encountered.

NIntegrate::nlim: \beta=Indeterminate is not a valid limit of integration.

Looking at the results this seems to be occuring when q vanishes; I'm getting results like

NIntegrate[\[Beta]*BesselJ[0, 0.*\[Beta]]*(E^(I*7.976042329074821*((\[Beta]*BesselK[1, \[Beta]]*HypergeometricPFQ[{1}, {1 + 3/2, 1 + 3/2}, \[Beta]^2/4] + 3*BesselK[0, \[Beta]]*HypergeometricPFQ[{1}, {1 + 3/2, 3/2}, \[Beta]^2/4])/3^2)) - 1), {\[Beta], 0, Infinity}, Method -> "ExtrapolatingOscillatory"]

Sure enough, evaluating f[0.00,18,4] reproduces these messages, wheras f[0,18,4] gives me a nice answer. Can someone explain to me what's going on here? Is this actually a bug or am I missing something about how Mathematica is handling the decimals?

Thanks in advance.

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# 0 vs 0.0 in numerical integrand- bug?

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