Root path is undefined

[vandanavk]

Description

root_path in build_r_docs is undefined. Since the
function call is commented out, this wasn't caught. Fixing
the path to avoid error in future.

Checklist

Essentials

Please feel free to remove inapplicable items for your PR.

• The PR title starts with [MXNET-$JIRA_ID], where $JIRA_ID refers to the relevant JIRA issue created (except PRs with tiny changes)
• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage:
• Unit tests are added for small changes to verify correctness (e.g. adding a new operator)
• Nightly tests are added for complicated/long-running ones (e.g. changing distributed kvstore)
• Build tests will be added for build configuration changes (e.g. adding a new build option with NCCL)
• Code is well-documented:
• For user-facing API changes, API doc string has been updated.
• For new C++ functions in header files, their functionalities and arguments are documented.
• For new examples, README.md is added to explain the what the example does, the source of the dataset, expected performance on test set and reference to the original paper if applicable
• Check the API doc at http://mxnet-ci-doc.s3-accelerate.dualstack.amazonaws.com/PR-$PR_ID/$BUILD_ID/index.html
• To the my best knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change

Changes

• Fixed root path in build R docs

Comments

• Related bug: 47 undefined variable errors with Pylint #11904

@aaronmarkham

[marcoabreu]

Why are we not building the R docs/

[vandanavk]

It was commented out by default - wasn't enabled later.
Building R docs fails on my machine though. @aaronmarkham have you been able to build R docs on your setup?

[vandanavk]

@cclauss

[aaronmarkham]

Actually, ran into this today on another PR I'm working on. I fixed it. I can make it a separate PR if you want something right away... otherwise it'll come in the docs build pipeline refactor I'm doing.

[aaronmarkham]

@marcoabreu The reason, according to the comment in mxdoc.py is that the latex requirement for R is too "heavy". It seems true, because I ran out of disk space on my instance while installing the dependencies.

These include:

sudo apt-get install \
    texinfo \
    texlive \
    texlive-fonts-extra \

To add this into a PR, it would seem I'd need to update the CI/install/R.sh and have it load these quite large deps.

WDYT about that?

[aaronmarkham]

I used a different approach on my fix, but I can align with this one if you guys plan to get this merged quickly. BTW, this will fail upon a second run because the file will already exist... so I made further changes to fix that... plus I'm massively changing this file anyways, but my PR should overlay on top of this just fine.
Please let me know what you want to do.

[marcoabreu]

No need for a rush, just take your time and do it right :)

About how much additional disk space are we talking here?

[vandanavk]

Closing this PR - Aaron's PR #11990 takes care of this.