change manually the scale of y-axis

[fatecasino]

Hi,
I have qwt plot. I am trying to "remove the noise" from y-axis.

For example, I have a data set where y-values vary between 0 and 10
If the y-axis is autoscale(true) then the y-axis will be from 0 to 10
Is it possible to make the y-axis scale to be from 0 to 100?
Which qwt function changes this?

I am planning to set a slider to control this function.

[d_stranz]

Doesn't QwtPlot::setAxisScale() do this? You probably have to set autoscale to false for that axis.

[fatecasino]

yes, indeed, the QwtPlot::setAxisScale() was the right function to do this.
I have connected a QSlider to "remove the noise", i.e. change the scale of the y-axis manually

void my2dPlot::removeNoise(int noiseFactor)
{
    double factorPerCentage =  noiseFactor/10;
    myPlot->setAxisScale(QwtPlot::yLeft, (1-factorPerCentage)*0.4*meanOfYvalues   , (1+factorPerCentage)*1.6*meanOfYvalues  ,0);
}

void my2dPlot::removeNoise(int noiseFactor)
{
    double factorPerCentage =  noiseFactor/10;
    myPlot->setAxisScale(QwtPlot::yLeft, (1-factorPerCentage)*0.4*meanOfYvalues   , (1+factorPerCentage)*1.6*meanOfYvalues  ,0);
}

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the only thing is that when I move the slider the whole transformation is a bit slow, but it definitely works.
The other things is that I created the removeNoise(int) by empirical studies only, and when I first move the slider the graph jumps up a bit and then it changes smoothly. If you have any optimizing suggestions on that, please post.