Problem with QLineSeries
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wrote on 21 Jun 2016, 19:28 last edited by
Hey,
I have a variable of the type QLineSeries. I add every second a new value and I want to keep not more than 10 values at the same time.
That means, if I insert value number 11, the first value has to be removed, the second value is the new first, third is now second, ...
Can anyone help me? I tried to use removePoints() or remove() but without success. -
Hey,
I have a variable of the type QLineSeries. I add every second a new value and I want to keep not more than 10 values at the same time.
That means, if I insert value number 11, the first value has to be removed, the second value is the new first, third is now second, ...
Can anyone help me? I tried to use removePoints() or remove() but without success.wrote on 21 Jun 2016, 21:06 last edited by Joel BodenmannI have never used
QLineSeriesor any of the related classes but as nobody has replied yet I'll just go ahead and write down my thoughts...Looking at the documentation there doesn't seem to be any method that implements the behavior that you are describing. Hence you'll have to do it yourself.
May I ask what exactly the problem was that you faced? It should only be a matter of correctly usingQXYSeries::replace()in afor()loop. -
Hi,
A possible faster way might be to retrieve the vector of points using pointsVector, pop the first item, append the new one and the call the replace overload with the version of the vector.
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wrote on 22 Jun 2016, 09:17 last edited by
Using pointsVector was a good hint! Thanks for the help!
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wrote on 22 Jun 2016, 09:31 last edited by
Can you please mark this topic as solved if you feel that your question has been answered?
Guide for that: https://forum.qt.io/topic/62700/hitchhiker-s-visual-guide-to-the-qt-forum
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