Git is a widely used version control system that allows tracking changes to files and code during software development. It provides features like branching, merging, and distributed collaboration. Data scientists can use Git and GitHub for version control, collaboration, and improving their personal branding by making their work public on GitHub. Key Git commands include git add to stage files, git commit to save changes locally, and git push to upload to a remote repository.

1. Data science Git
management
Arindam Banerjee
Data Scientist, Ericsson
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2. Version Control Systems (VCS)
• Version control is indispensable for any kind of development.
• Crucial for collaboration and teamwork.
• VCS record changes (revisions) to a file or set of files over time so that a
specific version can be recalled later.
• Part of Software Component Management.
• Revisions are generally thought as a directed tree - a directed acyclic graph.
• Revisions occur in sequence over time - can be arranged in order by revision
number or timestamp.
• Example: Git, Subversion, Mercurial, CVS etc.
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3. Git
• “Git is a distributed version-control system for tracking changes
in source code during software development.” — Wikipedia
• Most recognized and widely used modern version control system.
• Git is free and open-source software distributed under GNU General
Public License Version 2.
• Git is a mature, actively maintained open source project originally
developed in 2005 by Linus Torvalds.
• Designed with performance, security and flexibility in mind.
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4. Characteristics
• Support non-linear development - rapid branching and merging,
navigating a non-linear development history.
• Distributed – local version and remote version.
• Fast and scalable
• Toolkit-based design – C and Shell Script for speed and portability.
• Primarily developed on Linux but supports macOS and Windows.
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5. • Founded in 2008, GitHub.com - most well known and widely
used cloud-based, version control platform.
• It has been a subsidiary of Microsoft since 2018.
• Project files are stored at remote cloud location - repository.
• Once local changes are pushed to GitHub, remote version is
updated.
• Every change is logged, and commit is recorded.
• Allows rollback to a previous version.
• Anyone can access the remote repository and download it.
• Only registered users can contribute, discuss, manage
repositories, and review code changes.
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6. Branching
• One of the most important
and efficient features of git.
• A temporary copy of the
project can be made where
changes are made first
without breaking anything in
production version.
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7. For Data Scientists
• Software engineers, developers, and data scientists use GitHub to store
their work, read documentation of other’s work, and collaborate across
teams and organizations.
• For incremental development and deployment.
• CI/CD pipeline - DevOps operations.
• Faster release cycle - agile workflow with frequent smaller changes.
• Putting better and retrained models into production.
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8. Creating a git repo
• Make your project directory as you want it.
• Run git init inside the top directory of your project.
• After that a directory called .git will be created in that location.
• This is where git records all the commits and keeps track of everything.
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9. Cloning a git repo
• Instead of creating a repo from scratch, one can clone an existing repo
from remote location.
• Use git clone command with a URL of the remote repository.
• git clone
https://github.com/link/to/your/remote/repo
• Cloning creates a new directory and places the cloned Git repository in
it.
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10. Check repo’s status
• git status command is used to check the state of the repo.
• Run this command after running any other command.
• It shows information about untracked new files which are created in the
working directory.
• Tracked files which have been modified.
• Branch you are currently in.
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11. Information about commits
• git log command displays all the commits of a repository.
• It shows the SHA (a unique id), the author, the date, the commit message etc.
• git log --stat command shows the files modified in the commit, the
number of lines that have been modified (added/deleted) and a summary of
modification.
• git log --patch or git log –p shows the actual changes
made to a file.
• git show command shows the same result as git log –p
• git show XXXXXX command shows the changes made in the commit of
SHA XXXXXX.
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12. Add commits to repo
• Git’s staging step allows to continue making changes to the working
directory, and interaction with version control is required, it allows to
record changes in small commits.
• If a file needs to be committed, it should be kept in the Staging Index.
• git add file1 file2 … command is used to move files from
the Working Directory to the Staging Index.
• git add . is used to include all files of the current working directory
to stage.
• git rm --cached file1... command is used to unstage files if
you added wrong files by mistake.
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13. Git commit
• Use git status first.
• Configure at least username and email address to make commit to a Git
repository because this information is stored in each commit. Use below
mentioned command:
git config --global user.name “Firstname Lastname”
git config --global user.email
“your.email@example.com”
• Commit using the git commit command:
git commit -m “Your commit message goes here.”
• Use git log command to review the commit just made.
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14. Git Branching
• A powerful feature of Git.
• It represents an independent line of development. New commits are recorded in the
history for the current branch, and as a fork in the history of the project.
• git branch “new_branch_name” is used to create a new branch with the
given name.
• git checkout “new_branch_name” command is used to switch between
branches. Else even after branching, commits wil lbe made to main branch.
• git checkout –b “new_branch_name” – create and checkout to the new
branch.
• git branch command will show the active branch with an asterisk sign.
• git branch –d “new_branch_name” will delete the new branch.
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15. Git Merging
• git merge command is used to combine branches in Git.
• git merge “new_branch_name”
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16. Communicating with remote repo
• git fetch command downloads commits, files, and references from
a remote repository into local repo.
• Git isolates fetched content from existing local content, so that local
development work is no way affected.
• git pull on the other hand does that AND brings (copy) those
changes from the remote repository.
• git push command is used to upload local repository content to a
remote repository.
• Push exports commits to remote branches.
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17. GitHub for your Personal Branding
• Make your work public.
• Participate in Opensource Projects.
• Recruiters search through GitHub for potential job candidates.
• GitHub activity, repos, commits, documentation etc. are evidence of a
skilled practitioner.
• GitHub Pages - Websites for you and your projects. Hosted directly from
your GitHub repository. Just edit, push, and your changes are live.
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