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Gordey1978
27th September 2011, 16:57
Hello.

I use library «Qwt 6.0.0» for dynamic construction of schedules.

Problem number 1:
With a library of «Qwt» plotted as shown in the picture 1. These graphics are shown in the picture "data.jpg."
This chart has an axis of «Y» a logarithmic scale (m_plot-> setAxisScaleEngine (QwtPlot:: yLeft, new QwtLog10ScaleEngine ());). In picture 2 is a graph constructed with the help of another library.
How to Use the Library «Qwt» to ensure that the schedule looked something like the second picture? How to get to «qwt» prepared the correct scale of the axis «Y» schedule?

Problem number 2:
The graph constructed by the library «Qwt». Axis «Y» a logarithmic scale. How to get rid of it (see picture "3.jpg")?

P.S.:
data.jpg - Data for schedule construction
1.jpg - The schedule constructed by means of library "Qwt"
2.jpg - The schedule constructed by means of other library
3.jpg - The schedule constructed by means of library "Qwt"

Thanks.6900690169026903

Uwe
27th September 2011, 19:22
How to get to «qwt» prepared the correct scale of the axis «Y» schedule?
Like always: you can use autoscaling or explicitly assign a scale. See:


QwtPlot::setAxisScale
QwtPlot::setAxisScaleDiv
QwtPlot::setAxisAutoScale



The graph constructed by the library «Qwt». Axis «Y» a logarithmic scale. How to get rid of it (see picture "3.jpg")?
Don't know - you didn't write, what your application does so I can only guess: maybe you misunderstood the meaning of a parameter ?

Uwe

Gordey1978
28th September 2011, 04:09
Like always: you can use autoscaling or explicitly assign a scale. See:


QwtPlot::setAxisScale
QwtPlot::setAxisScaleDiv
QwtPlot::setAxisAutoScale



Don't know - you didn't write, what your application does so I can only guess: maybe you misunderstood the meaning of a parameter ?

Uwe

On the 3.jpg picture shows that the Y-axis labels overlap. This is not correct.

Uwe
28th September 2011, 07:06
Obviously you have configured your scale to show thousands of labels ( major ticks )- what can't be displayed better on a scale with something about 200 pixels. It's not about overlapping labels only - the scale is misconfigured at all.

Uwe