I need vertical axis to have different scale above and below zero.
For ex. I want 20..0 in upper half and 0..200 in bottom half.
But zero level should remain in geometry center of the entire plot.
How can I implement this behavior using Qwt?

I tried two separate plots in vertical stack. And this is almost it but I cannot eliminate the spacing between them because plot’s axises extend beyond the plot boundaries.
Looks like this

I want something like this