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Thread: Problems with Dial/Compass and with logarithmic scale

  1. #1
    Join Date
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    Question Problems with Dial/Compass and with logarithmic scale

    Hello,

    1) How can I change the font size on a Dial/Compass?
    My widget is derived from QwtCompass and I want to change the font size of the labels.
    How can I do that?

    2) When I use the Log10Scale in a plot e. g. with a "stick" curve style, the sticks "hang down" from the ceiling instead of doing like expected.
    I guess this is because there's no 0 on the y-axis with a logarithmic scale.
    What can I do about it to use a logarithmic scale with sticks drawn "correctly"?

    Thanks in advance

    Alu

  2. #2
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    Default Re: Problems with Dial/Compass and with logarithmic scale

    1) How can I change the font size on a Dial/Compass?
    compass->setFont(...);
    2) When I use the Log10Scale in a plot e. g. with a "stick" curve style, the sticks "hang down" from the ceiling instead of doing like expected.
    I guess this is because there's no 0 on the y-axis with a logarithmic scale.
    You need to assign a baseline ( f.e QwtPlotCurve::setBaseline(1.0e-100) ) with a value, that is inside the range of a logarithmic calculation. Be careful, that the value is not too small compared to your axis scale to avoid integer overruns.

    Uwe

  3. #3
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    Default Re: Problems with Dial/Compass and with logarithmic scale

    Thank you!

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