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gyre
11th December 2007, 15:57
Is there a way how to do this using Qwt:
I want to measure some data for a several hours lets say...And I need to display them in a plot...The problem is that I couldnt find anywhere how can I set a range of x-axis ...
I want it to be changed dynamically after a certain time interval...like to enlarge by 10 after each 5 seconds...
Does anyone have a clu how to do that ?
Thanks

Uwe
11th December 2007, 16:21
Start with looking at the cpuplot example.

Uwe

gyre
11th December 2007, 16:27
Start with looking at the cpuplot example.

Uwe

Aha...I wouldnt know that something like that I can find in that example...I was looking at realtime plots and other examples like that...thanks Ill have a look...

What if I was just changing the axis scale upon some timer event using this method of QWTPlot ?
setAxisScale()

Uwe
11th December 2007, 17:02
What if I was just changing the axis scale upon some timer event ...
I don't know enough about your application, but in general it should be enough to assign your new points to the curve and do a replot. The autoscaler will do the rest.

If you store your data in your own type of container I recommend to write your own QwtData bridge. This way you don't need to copy anything and a single replot every couple of seconds will do what you want.

Uwe

gyre
11th December 2007, 17:13
If you store your data in your own type of container I recommend to write your own QwtData bridge. This way you don't need to copy anything and a single replot every couple of seconds will do what you want.


Thanks...Ive searched the docs and what you are saying seems reasonable...