Set padding of Y data limits prior to autoscaling.
m times the data interval will be added to each end of that interval before it is used in autoscaling. For example, if your data is in the range [0, 2], a factor of m = 0.1
will result in a range [-0.2, 2.2].
Negative values -0.5 < m < 0 will result in clipping of the data range. I.e. for a data range [0, 2], a factor of m = -0.1
will result in a range [0.2, 1.8].
© 2012–2021 Matplotlib Development Team. All rights reserved.
Licensed under the Matplotlib License Agreement.
https://matplotlib.org/3.5.1/api/_as_gen/matplotlib.axes.Axes.set_ymargin.html