Showing Legend Under Matplotlib Plot With Varying Number Of Plots

I'm working on a program that allows users to put a different number of plots onto an axis. I need to show the legend, and the plot labels are long so I think it is best to show th

Solution 1:

A way to correct the axes position, such that the legend has enough space is shown in this question's answer: Creating figure with exact size and no padding (and legend outside the axes)

For the legend to sit on the bottom the solution is much simpler. Essentially you only need to subtract the legend height from the axes height and move the axes by the amount of the legend height towards the top.

import matplotlib.pyplot as pltfig= plt.figure(figsize = [3.5,2]) 
ax = fig.add_subplot(111)
ax.set_title('title')
ax.set_ylabel('y label')
ax.set_xlabel('x label')
ax.plot([1,2,3], marker="o", label="quantity 1")
ax.plot([2,1.7,1.2], marker="s", label="quantity 2")

def legend(ax, x0=0.5,y0=0, pad=0.5,**kwargs):
    otrans = ax.figure.transFiguret= ax.legend(bbox_to_anchor=(x0,y0), loc=8, bbox_transform=otrans,**kwargs)
    ax.figure.tight_layout(pad=pad)
    ax.figure.canvas.draw()
    tbox = t.get_window_extent().transformed( ax.figure.transFigure.inverted() )
    bbox = ax.get_position()
    ax.set_position([bbox.x0, bbox.y0+tbox.height,bbox.width, bbox.height-tbox.height]) 

legend(ax,y0=0, borderaxespad=0.2)

plt.savefig(__file__+'.pdf')
plt.show()