Using HashMap over QMap

[Kartik Ramesh]

Thanks for the heads up, I'll take care of this.

Kartik

On Thu, 9 Jul 2020, 23:15 Maik Qualmann, <metzpinguin at gmail.com> wrote:

> One more thing about the QMap. Please no longer use insertMulti(). Then
> use a
> QMultiMap. The insertMulti() function is deprecated in QT-5.15. I have
> already
> replaced some, but there are still some. With new code, we have to be
> careful.
>
> Maik
>
> Am Donnerstag, 9. Juli 2020, 19:32:47 CEST schrieb Kartik Ramesh:
> > Thank you for the insight. I wasn't aware that a QMap would perform
> better
> > for smaller entries. Since my map would contain only small number of
> > entries on average (as number of faces in an image will not be very
> large),
> > I think I should stick with the QMap implementation.
> >
> > Thanks
> > Kartik
> >
> > On Thu, 9 Jul 2020, 22:54 Maik Qualmann, <metzpinguin at gmail.com> wrote:
> > > A QHashMap brings a speed advantage for a large number of entries,
> because
> > > access is constant time. A QMap can be faster with a few, say up to 200
> > > entries. With Qt4 there were sometimes problems if the key was a
> string in
> > > a
> > > QHashMap, which was not unique when converted to a hash. That should no
> > > longer
> > > occur with Qt5. So, many thousands of entries with a lot of access ->
> > > QHashMap. Keep in mind that the keys of a QMap are sorted
> automatically.
> > >
> > > Maik
> > >
> > > Am Donnerstag, 9. Juli 2020, 15:24:31 CEST schrieb Kartik Ramesh:
> > > > Hi all,
> > > >
> > > > I was working on categorizing Face Suggestions by Suggested Name.
> This
> > > > would lead to a grouping of similar faces, which would be
> particularly
> > > > helpful in the Unconfirmed Tag View.
> > > >
> > > > To do the categorization, I have been able to implement methods to
> > >
> > > obtain a
> > >
> > > > Map of Face Regions -> Suggested Names for each Image. This would
> have
> > > > multiple elements if an image has multiple faces. I have committed
> the
> > > > implementation already.
> > > >
> > > > Since, I don't have any reason for my keys to be sorted, I was
> wondering
> > >
> > > if
> > >
> > > > I should use a HashMap instead of a QMap?  I have currently used a
> QMap
> > > > because all methods related to Faces use it.
> > > >
> > > > Thanks in advance
> > > > Kartik
>
>
>
>
>
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