exclude lines from a loose_autoscale_view function

I’m not sure if this is going to work to solve an issue I’m having, but I’d like to try it before asking a much more complex question. I have a function, loose_autoscale_view(), that is based on the autoscale_view function in mpl but allows margin arguments to push the margins out a bit more.

I’d like to try to alter it to allow certain lines belonging to an axis to not be taken into consideration when autoscaling. I can alter it to accept a list of lines to be excluded, but then I don’t know how to exclude them when calculating the autoscaling. I think the key line in the function is this one:

bb = mtransforms.BboxBase.union(dl)

because that union gets the sub-BBoxes for all the lines…so is there a way to exclude some? Or is there a better approach?

Thanks. The function is below.

-Che

def loose_autoscale_view(self, subplot, xmargin, ymargin, tight=False, scalex=True, scaley=True):
“”"
autoscale the view limits using the data limits. You can
selectively autoscale only a single axis, eg, the xaxis by

    setting *scaley* to *False*.  The autoscaling preserves any
    axis direction reversal that has already been done.
   
    I have added a way to make it not quite so tight using xmargin and ymargin. 

    """
   
    # if image data only just use the datalim
    #if not self.subplot._autoscaleon: return
    if scalex:
        xshared = subplot._shared_x_axes.get_siblings(subplot)

        dl = [ax.dataLim for ax in xshared]           
        bb = mtransforms.BboxBase.union(dl)
        xdiff = bb.intervalx[1] - bb.intervalx[0]
        x0 = bb.intervalx[0]-xdiff * xmargin

        x1 = bb.intervalx[1]+xdiff * xmargin
    if scaley:
        yshared = subplot._shared_y_axes.get_siblings(subplot)
        dl = [ax.dataLim for ax in yshared]
        bb = mtransforms.BboxBase.union(dl)

        y0_untampered = bb.intervaly[0]-(bb.intervaly[1])
        y0 = bb.intervaly[0]-(bb.intervaly[1]* ymargin)
       
        y1_untampered = bb.intervaly[1]
        y1 = bb.intervaly[1]* (1+ymargin)

       
    if (tight or (len(subplot.images)>0 and
                  len(subplot.lines)==0 and
                  len(subplot.patches)==0)):
        if scalex:
            subplot.set_xbound(x0, x1)

        if scaley:
            subplot.set_ybound(y0, y1)
        return
    if scalex:
        XL = subplot.xaxis.get_major_locator().view_limits(x0, x1)
        subplot.set_xbound(XL)

    if scaley:
        YL = subplot.yaxis.get_major_locator().view_limits(y0, y1)
        subplot.set_ybound(YL)