DOC: add tutorial explaining imshow origin and extent#10947

Merged

jklymak merged 4 commits intomatplotlib:masterfrom

tacaswell:doc_imshow_extent

May 2, 2018

Commits on Apr 3, 2018

DOC: add tutorial explaining imshow *origin* and *extent*
tacaswell
committed

Commits on Apr 9, 2018

DOC: tweak helper method kwargs and example data
tacaswell
committed

Commits on Apr 26, 2018

DOC: add index labels
timhoffm
committed

Commits on May 2, 2018

DOC: Rewrite parts of imshow origin/extent handling
timhoffm
committed