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GalAster

9:39 AM

```
class[data_Association][f_Symbo]
```
HoldAll seem can't be set to `class` and acts on `f`?

6 hours later…

C. E.

3:33 PM

@GalAster True, this has been discussed e.g. here.

2 hours later…

Michael E2

5:21 PM

From the files of GIGO:

Assuming[x > 0 && y > 1,
 Integrate[Exp[(-x)*x - y*y], {x, -Infinity, 0}, {y, -Infinity, Infinity}]]
Assuming[x > 0 && y > 1,
 Integrate[Exp[(-x)*x - y*y], {x, -Infinity, -1}, {y, -Infinity, Infinity}]]
Assuming[x > 0, Integrate[Exp[(-x)*x], {x, -Infinity, -1}]]
(*
  Pi/2
  Integrate[1, {x, -Infinity, -1}, {y, -Infinity, Infinity}]
  (1/2)*Sqrt[Pi]*Erfc[1]
*)

The second integral is claimed to diverge (well, the resulting output does diverge).

It's hard to claim it's a bug, but rewriting the integrand as 1 seems wrong.

2 hours later…

Meta

7:07 PM

Q: Always wrong about distributions

There is a certain user, let's call them A., that has the tendency to comment on every post that mentions Schwartz distributions, usually accompanied by a downvote. These comments are completely unhelpful (they do not serve the purposes outlined in the help centre). In fact, they are always of th...