bug: merge fails when merging on column which contains values containing underscores

[jpjagt]

Describe the bug
danfojs-browser/src/core/merge.js stores sets of values by joining them with an underscore, and later splitting on underscore. however, when the values themselves contain underscores, this becomes problematic, as this split causes nonsensical columns to be defined when indexing the data.

To Reproduce
Steps to reproduce the behavior:

1. create two dataframes, both with the same column consisting of values which contain underscores.
2. attempt to dfd.merge those dataframes.
3. get an error: Column length mismatch. You provided a column of length 1 but data has length of 3 (e.g.)

Expected behavior
the two dataframes should be merged without any trouble.

Desktop (please complete the following information):

• OS: macOS, but any OS
• Browser any browser
• Version 0.2.5

[jpjagt]

i have submitted a PR which fixes this bug for both browser and node: #167

please tell me what you think!

thank you for your awesome work on this package! ❤️

[jpjagt]

by the way, i noticed the following changes in my git status:

modified:   danfojs-browser/lib/bundle.js
modified:   danfojs-browser/lib/bundle.js.LICENSE.txt
modified:   danfojs-browser/lib/bundle.js.map

i did not add this to the PR, because i did not know if i'm supposed to. but if i should add those changes, do let me know!

[risenW]

i have submitted a PR which fixes this bug for both browser and node: #167

please tell me what you think!

thank you for your awesome work on this package! ❤️

Thanks for taking out time to fix this! 😃 I'll certainly review and get this merge ASAP.

[risenW]

by the way, i noticed the following changes in my git status:

modified:   danfojs-browser/lib/bundle.js
modified:   danfojs-browser/lib/bundle.js.LICENSE.txt
modified:   danfojs-browser/lib/bundle.js.map

i did not add this to the PR, because i did not know if i'm supposed to. but if i should add those changes, do let me know!

Well not really, we committed the lib builds earlier when we were supporting install via Github. We don't do that anymore, so I'll add that to the git ignore file.