[texhax] Centring \ddot above \widehat.

[Enrico Schumann]

On Sat, 10 Mar 2018, Rolf Turner writes:

> Putting a "double dot" above a wide hat seems to centre the dots over
> the underlying symbol, and thus puts them somewhat to the left of the
> peak of the wide hat --- which looks wrong to me.
>
> A Google search turned up only information about a single dot and hat;
> the posting
>
>> https://tex.stackexchange.com/questions/317603/how-to-put-a-dot-accent-above-a-hat-accent-in-math-mode
>
> indicated that using amsmath would get things right --- and indeed it
> does in this instance.  However using amsmath seems to have no impact
> upon the "double wide" case.  Is there any remedy?
>
> I have attached the LaTeX source and the pdf output of a minimal
> reproducible example.
>
> Thanks for any advice.
>
> cheers,
>
> Rolf Turner

In Plain TeX, there is a command \skew. You could try

  \[
  \textrm{whatever} = \skew3\ddot{\widehat{Q}}
  \]

Instead of skew3, you may use skew1, skew2,...
It's described in the TeXBook, Chapter 16. Quote:
"The idea is to fiddle with the amount of skew
 until you find what pleases you best."

-- 
Enrico Schumann
Lucerne, Switzerland
http://enricoschumann.net