- #1

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I am trying to evaluate the following integral numerically in MATLAB

[tex]\int_0^{\infty}\frac{e^{-jt}E_1^2(-jt)}{t}\,dt[/tex]

where ##j=\sqrt{-1}##, and ##E_1(x)## is the exponential integral.

My code is

Code:

```
fun = @(x) (exp(-1i*x).*(expint(-1i*x)).^2)./x;
q = integral(fun,0,Inf)
```

but I get the following warning message

Warning: Reached the limit on the maximum number of intervals in use. Approximate bound on error is 3.2e+04. The integral may not exist, or it may be difficult to approximate numerically to the requested accuracy.

What does this mean? Does it mean that the integral doesn't exist? Or I need to increase the precision?

Thanks