intg: results differ substantially from those from Wolfram Alpha, which are correct?

[Ginters Bušs]

Dear all,

Let's integrate:

function y=f(x, a,
sigma),y=(1/sqrt(2*%pi))*log(abs(a+sigma*x))*exp(-(x^2)/2),endfunction

out=intg(-1e+2,1e+2,list(f,1,.1))

out=8.605D-49

but Wolfram Alpha gives out= -0.111

which is a totally different answer.

I've noticed that intg and integrate incline to give values close to zero
when boundaries tend to infinity.   So, I trust Wolfram Alpha more.  How to
get around the apparent mistakes in intg, integrate (particularly, I'm
interested in indefinite integrals)?

Gin.
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