Hi !

I have a bizarre output from the following script:

```
import openturns as ot
u = ot.Uniform(0.0, 1.0)
n = ot.Normal(0.0, 1.0)
z1 = u * n
z1.setDescription(["u * n"])
graph = z1.drawPDF()
z2 = n * u
z2.setDescription(["n * u"])
graph.add(z2.drawPDF())
graph.setColors(["dodgerblue3", "darkorange1"])
graph.setXTitle("X")
```

The script draws the PDF of the random variables:

and

where U \sim \mathcal{U}(0, 1) and N \sim \mathcal{N}(0,1).

This produces:

This is surprising, because both PDFs should match (the variables are independent).

The PDF writes:

and

I guess that there might be an integration issue at 0, but I am not sure if this singularity can be integrated.

In general, should the operators +, -, *, / commute mathematically and numerically?

Regards,

Michaël