FIX: properly set x/y limitsMNT: add tolerance to colorbar locator methods

* Rectified plot errorThe plot shown on the page:https://matplotlib.org/tutorials/introductory/usage.html#sphx-glr-tutorials-introductory-usage-pyWill be possible only if plt.show() is outside the loop* Added corrections in docs as per requirements* Commented the code block to remove plot rendering* Added ::* corrected trailing spaces and bad indentation* Removed E402

…abelsFIX: colorbar re-check norm before draw for autolabels

When plotting 10000 lines, this gives a ~10% improvement in performance.

If there's no margin to be added, we don't need sticky edges, but ifautoscaling is off, we _also_ don't need the sticky edges. This saves alot of time when plotting many artists, like inmatplotlib#12542.

Avoid quadratic behavior when accumulating stickies.

Disable sticky edge accumulation if no autoscaling.

…riptionDoc: Clarify horizontalalignment and verticalalignment in suptitle

…nto hist2d_density* 'hist2d_density' ofhttps://github.com/thoo/matplotlib:  Add density in hist2d