BUGFIX: fix act-walk caching

@serguei.ossokine pointed out that the act-walk is not working with parallelization, the reason for the issue is that the object gets pickled at each call to the sampler and so instance-level attributes aren't being preserved properly.

To fix this, I made the _cache a class-level attribute. I also made sure that the cache is wiped at the beginning of sampling in case people run multiple analyses with this method using a single script/session in a jupyter notebook.

I removed the use of premade instances of the walking methods as it wasn't achieving anything.

EDIT: there was an equivalent problem with the rwalk method that had a similar solution

added <10 lines Bug Sampling labels

requested review from @gregory.ashton and @sylvia.biscoveanu

added 1 commit

• 3bd9e531 - FORMAT: fix formatting issues

Compare with previous version

added 1 commit

• 76e813ee - BUGFIX: typo in _cache attribute

Compare with previous version

mentioned in merge request emfollow/gwcelery!1091 (merged)

changed milestone to %2.0.1

added 1 commit

• 06985f91 - BGUFIX: track act for rwalk method

Compare with previous version

changed the description

added 1 commit

• dff3a72c - TYPO: add missing blank line

Compare with previous version

added 1 commit

• f6017840 - TEST: bugfix in dynesty test

Compare with previous version

approved this merge request

Looks good to me!

mentioned in merge request !1231 (merged)

merged

mentioned in commit e019b5a2

picked the changes into the branch cherry-pick-e019b5a2 with commit ac05c0f6

mentioned in commit ac05c0f6

picked the changes into the branch release/2.0.x with commit 0a410d03

mentioned in commit 0a410d03