Remove clear memory

[timokau]

Description

Removing clear_memory and hash_file to reduce complexity and get one step further towards stateless / scikit-learn compatible estimators.

Motivation and Context

See description.

How Has This Been Tested?

Tests and pre-commit.

Does this close/impact existing issues?

Fixes #148, step towards #94 / #116.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.

[codecov]

Codecov Report

Merging #150 into master will increase coverage by 0.47%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #150      +/-   ##
==========================================
+ Coverage   57.77%   58.25%   +0.47%     
==========================================
  Files         113      113              
  Lines        6960     6848     -112     
==========================================
- Hits         4021     3989      -32     
+ Misses       2939     2859      -80     

Impacted Files	Coverage Δ
csrank/choicefunction/cmpnet_choice.py	94.59% <ø> (+2.28%)	⬆️
csrank/choicefunction/fate_choice.py	95.12% <ø> (+4.21%)	⬆️
csrank/choicefunction/feta_choice.py	66.20% <ø> (+0.66%)	⬆️
csrank/choicefunction/ranknet_choice.py	94.73% <ø> (+4.49%)	⬆️
csrank/core/cmpnet_core.py	97.72% <ø> (+10.34%)	⬆️
csrank/core/fate_network.py	70.15% <ø> (+3.49%)	⬆️
csrank/core/feta_network.py	64.89% <ø> (+3.43%)	⬆️
csrank/core/ranknet_core.py	97.72% <ø> (+10.34%)	⬆️
csrank/discretechoice/cmpnet_discrete_choice.py	100.00% <ø> (+3.22%)	⬆️
csrank/discretechoice/fate_discrete_choice.py	100.00% <ø> (+5.88%)	⬆️
... and 8 more

[kiudee]

Looks good to me, thank you.

I agree with this simplification. Should it turn out that we need to clear memory in between different fit calls, we should anyway check what the best practices are.

[timokau]

Travis has succeeded but that information apparently somehow got lost in transit. Can we restart that check?

[kiudee]

Restarting the build somehow did not fix it. I think the only thing we could do is to push something to trigger the whole process again. If that does not work I will investigate if there is some connection issue between Github and Travis CI (so far there is no error message).

[kiudee]

Looks like this issue:
https://travis-ci.community/t/known-issue-travis-ci-reports-expected-waiting-for-status-to-be-reported-on-the-github-status-api-but-the-status-never-arrives/1154
I deactivated the status check for now until I update travis to the new format.

[timokau]

Yeah I saw that too, very weird that it is just one report (all the previous ones seem outdated) and it isn't acknowledged yet.

Anyway, thanks for the review!