I'd recommend using https://doc.qt.io/qt-5.10/qxyseries.html#replace-5

Replacing points one by one destroys a cpu. The metrics for me was just not even worth measuring - it was just an immediate hell no - forget that - I need faster updates. I like declarative QML for gui as a preference but calling replace on a single point fires way too many signals and takes way too long.

I throw my QML LineSeries to a QXYSeries and call replace in c++

In the future I'll probably just declare my series in C++. I wish I could have a better supported hybrid of c++ and QML charts but I have this working very fast using useOpenGL : true; (you can also c++ setUseOpenGL(true) )

@DrakeM said in Gaps in QLineSeries:

When using line series, we've had severe performance problems. We end up with thousands of series to handle all of the gaps and have to create parallel scatter series because we want icons for each point that aren't part of the standard icon set.

We pay a huge cost both constructing and destructing the series. Seems like it may be refreshing on each add series, but even removeAllSeries is slow. Have tried many things to suspend the painting, but with no timing effect.

Any ideas on how to have many gaps without destroying performance?

You can generate gaps by adding qQNaN()'s to the series. However, it doesn't seem to work with append() (it ignores NaN's), but setting the whole point data at once takes NaN's into account.

I found a solution and post it here: link

Super :)
oh it must have "()" on.
The syntax is pretty funky via the automation server.
Good work.

@KRHC hi and welcome to devnet,

You need QApplication if you use anything that relies on the widgets module. Otherwise, there's no need for it and you would just bloat your deployment for no good reason.

@corianderop Hi I am also stuck in a similar situation did you figure out a solution for it ?