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Why does Wolfram|Alpha give inconsistent result for $\int_0^\infty \frac{e^{x-x^2}-e^{-x-x^2}}{x}~dx$? [closed]

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Why Wolfram gives inconsistent result for :

$$I=\int_0^\infty \frac{e^{x-x^2}-e^{-x-x^2}}{x}~dx$$

As shown in the picture below, the analytical integration gives $-i\pi$, but numerical integration gives $1.93193$. The result must be a real number, but why Wolfram gives a complex result for the analytical integration?

What I suspect is Wolfram might treat this integral as Frullani integral, where $f(x)=e^{x-x^2}$, and $f(-x)=e^{-x-x^2}$. We get

$$\int_0^\infty \frac{e^{x-x^2}-e^{-x-x^2}}{x}~dx=\int_0^\infty \frac{f(x)-f(-x)}{x}~dx=(f(\infty)-f(0))\ln\left(\frac1{-1}\right)=-i\pi$$But this is WRONG!

Update: I use Mathematica 10.0 and Wolfram Alpha online, and both of them give the complex result.

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