Qwtplot and Plotter Tab editable?

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vestige
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Qwtplot and Plotter Tab editable?

Post by vestige »

Hi

I currently using the plotter tab in the cfclient but I can't edit X and Y axis if it possible how can i edit it?. Also i also interest in Qwtplot how can I able to use it within the cfclient?


Thank you In advance
marcus
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Re: Qwtplot and Plotter Tab editable?

Post by marcus »

Hi,

In the latest version of the client you can change Y by scrolling (or using the settings in the lower right part of the tab). You can also change X by specifying the number of samples you would like to show. The issue that we have seen with PyQtPlot (and all other plots that we tried) is that they don't handle plotting a large number of points at higher update rates very well. It really takes a lot of CPU time. At first we had a QwtPlot implementation that we tough was very slow, then we made our own version that was faster but it didn't have any features and finally we ended up at PyQtPlot which we thought was a good middle point.
vestige
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Re: Qwtplot and Plotter Tab editable?

Post by vestige »

Hi marcus

Thankyou for the reply. So by changing X did it need to be specify when you do in the logging configuration?. And Y axis it can be scrolling down on the plotter tab while it keep getting data on Real time ?
marcus
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Re: Qwtplot and Plotter Tab editable?

Post by marcus »

No you don't need to change the logconfig, you can do this in realtime. The capping of values is done in the plot, so if you change the number of samples then it will instantly take effect. For Y it's only a setting of how to view the data. So if you scroll it instantly zooms in/out or if you press the left mousebutton down you can drag the graph up/down.
vestige
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Re: Qwtplot and Plotter Tab editable?

Post by vestige »

marcus wrote:No you don't need to change the logconfig, you can do this in realtime. The capping of values is done in the plot, so if you change the number of samples then it will instantly take effect. For Y it's only a setting of how to view the data. So if you scroll it instantly zooms in/out or if you press the left mousebutton down you can drag the graph up/down.
I'm quite get it now I will try out as soon as I can :D. I'm currently try to plot the data from barometer and altitude hold.

I have a question that very out of this topic I'm very curious that in Barometer sensor I'm trying to test that the when I have set it into certain high (E.g 5 meters) and I would like to know that the relationship between the Pressure and Temperature. In the Logging config I just select only Pressure and Temperature but the graph mostly stay the same So i just wonder that did i do anythings wrong about it? :( . As I understand that the the higher the altitude the lower the pressure and temperature. I just want to test that the sensor is accurate or not.

I'm feel sorry for asking something that out of topic marcus :cry:
marcus
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Re: Qwtplot and Plotter Tab editable?

Post by marcus »

If you are logging baro.pressure and baro.temp then the scale of the plot is a problem if you would like to see both. Since temp is low (~20) and pressure is high (~1000) you will not see small variations in either. You will need to zoom in Y to see variations.
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