improve docs, add doctests in power_series*

[rwst]

Improve documentation of power series.

Component: doctest coverage

Keywords: series

Author: Ralf Stephan

Branch/Commit: 3ea4f9b

Reviewer: Peter Bruin

Issue created by migration from https://trac.sagemath.org/ticket/16199

[rwst]

Branch: u/rws/improve_docs__add_doctests_in_power_series_

[rwst]

New commits:

3102007	14053: doctests added; typos fixed
8356a6f	move TODO into ticket 16194
abc97b4	Merge branch 'develop' into t/14053/bring_doctest_coverage_for_rings_power_series__to_100_
cc54f6e	improve docvumentation; add doctests

[rwst]

Commit: cc54f6e

[pjbruin]

Reviewer: Peter Bruin

[pjbruin]

comment:4

Looks good. Just a few small comments (all about methods of the class PowerSeries):

• The examples block in __hash__() is not correctly indented.
• In _cmp_c_impl(), put single backquotes also around the "g" in "Magma would declare f and g unequal.`
• In is_unit() and several other methods below it, please try to split the first sentence(s) into two paragraphs so that the first one is just one line (or at most two lines) long.
• In sqrt() it might be slightly better to say "Return a square root of self."
  Once you fixed these you can set it to positive review.

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

e935206	Merge branch 'develop' into t/16199/improve_docs__add_doctests_in_power_series_
3ea4f9b	16199: documentation cosmetics

[sagetrac-git]

Changed commit from cc54f6e to 3ea4f9b

[rwst]

comment:6

Thanks for the review.

[vbraun]

Changed branch from u/rws/improve_docs__add_doctests_in_power_series_ to 3ea4f9b