Plotting geospatial data with git branching

Week 5 - Discussion section

🎃 Happy Halloween! 🎃

This week you will wrangle data about earthquakes and collaborate with a partner using git branches. In this discussion section, you will:

  • Break down a question into accessible data wrangling steps
  • Import and plot different types of geospatial data
  • Practice git branching and pull requests with a partner

General directions

  • Add comments as appropriate along your code following the course commenting standards.
  • Include markdown cells in between your code cells to add titles and information to each exercise.
  • Commit every time you finish a major step. Remember to write informative commits in the imperative mood.

About the data

For this task you will use two datasets.

The first dataset is simplified data from the USGS Earthquakes Database. This data is in tabular format and has the following columns:

Column Description
time date and time of event (all events from 2014)
latitude decimal degrees [-90,90]
longitude decimal degrees [-180,180]
depth depth of the event (km)
mag magnitude of event
id event identifier
place where the event took place
type type of event

This is the same dataset you used in assignment 1. You can access the data through this link.

Further information about the dataset can be accessed in the ANSS Comprehensive Earthquake Catalog (ComCat) Documentation.

The second dataset is Natural Earth’s low resolution cultural boundaries data. These are useful to make maps of the whole world, although they might not be suitable for mapping individual nations or finer geospatial analysis. You can access the “Admin 0 – Countries” dataset available in this link.

Setup

With your partner, decide which one of you will be Partner 1 and Partner 2. Then complete the following setup:

Partner 1:

  1. Create a new GitHub repository titled earthquake-branching. Add a README, a Python gitignore, and an MIT License.

  2. Add your partner as a collaborator on your remote repository.

  • In your remote repo, navigate to Settings
  • Click on “Collaborators” > “Add People”
  • Add Partner #2’s GitHub username as a collaborator.

  1. Clone your new repository in your EDS 220 folder.

  2. Create a new Python notebook inside your earthquake-branching directory and rename it to section-5-earthquakes.ipynb.

  3. Use the terminal to commit and push this file to your remote repository.

Partner 2:

No setup right now!

Get started

Complete exercises 1, 2, and 3 together on Partner #1’s computer. Don’t worry, Partner #2, since you are a collaborator, you have access to this repository like it is your own!

1. Brainstorm

In this session you will recreate the following map:

  1. Individually, write down high-level steps on how you would explore and wrangle the data to produce this map. Do not code anything yet.

  2. Discuss your high-level steps with your team. What do you see as potential challenges to implementing your plan?

  3. As a team, select an initial plan for recreating this plot.

2. Recreate the plot

Use your plan as a starting point to recreate the plot.

  • You may (or may not) need to look online to carry out some of the steps in your plan. It is completely fine to seek help online! Resourceful troubleshooting is a key skill in data science.

  • It’s ok if your initial plan changes as you work with the data and discuss challenges with your team! This brainstorm is to create a shared starting point.

Don’t forget to write informative commits every time you finish a major step.

3. Update your notebook

  1. Include any takeaways from the map in a markdown cell after your plot.

  2. Go over your notebook and add markdown cells with appropriate titles and subtitles to guide the reader through the different steps in your workflow.

  3. Include a markdown cell at the top with a title for your notebook and a description of what it is about.

Commit and push all changes to your remote repository!

4. Branching

It’s time to practice some branching! Creating branches on GitHub encourages collaboration on GitHub repos without all the merge conflicts. A branch gives you an isolated environment to make changes without immediately affecting the main branch.

Partner 2 tasks

  1. Check your email for the invitation to the earthquake-branching repository your partner added you as a collaborator to. Accept the invitation.

  2. Clone the earthquake-branching repository to your workbench.

  3. Create a new branch to make edits on with the following command in the terminal. This command is creating a new branch and calling it partner2-branch. Be sure to update “partner2” with Partner #2’s name.

git checkout -b partner2-branch
  1. Double check that you are on your new branch. Run the following code in the terminal. If it returns an asterisk (*) next to your new branch name, you are on your new branch!
git branch

The output should look something like this:

* partner2-branch
main
  1. Set the upstream remote branch

Before pushing, you need to set the upstream branch. This sets up a tracking relationship between your local branch and your remote branch. You will only need to set this up once for each individual branch you make.

git push --set-upstream origin partner2-branch
  1. Make the following changes on your new branch:
  • Follow the documentation for plt.figtext to add your name as an author on this plot in the bottom right corner.
  1. Push your changes!

Run git pull to make sure you have the most up to date remote changes. Then run git push.

Comprehension check

Where did you just push your changes to? Where do you need to go to check the changes you just made on your remote repository?

Create a pull request!

You now have a branch called main that has the plot you and your partner created. You also have a branch called partner2-branch that has Partner #2’s name as an author. We want to merge the changes from this partner2-branch into our main branch. To do so, we will create a pull request.

  1. Navigate to the remote repository on github.com
  2. Click on the pull request icon
  3. Click “New Pull Request”
  4. In the compare changes tab, merge your branch into the main branch

  1. Click “Create Pull Request”
  2. GitHub will compare your branch with main and make sure there are no conflicts. If there are no conflicts, a “Merge pull request” option will appear. Click on this.
  3. Write a commit message that encompasses the changes you are merging into the main branch
  4. Finally, click “Confirm merge”. You have just merged your branch into main!

Partner 1 tasks

Partner 1 will now follow a similar sequence of tasks, with a very important addition. The remote repository now contains changes from your partner that you do not have locally. You need to do a git pull to avoid merge conflicts.

  1. In the workbench terminal, run git pull to make sure you have all changes that your partner made locally.

  2. Create a new branch to make edits on with the following command in the workbench terminal. This command is creating a new branch and calling it partner1-branch. Be sure to update “partner1” with Partner #1’s name.

git checkout -b partner1-branch
  1. Double check that you are on your new branch. Run the following code in the terminal. If it returns an asterisk (*) next to your new branch name, you are on your new branch!
git branch

The output should look something like this:

* partner1-branch
main
  1. Set the upstream remote branch

Before pushing, you need to set the upstream branch. This sets up a tracking relationship between your local branch and your remote branch. You will only need to set this up once for each individual branch you make.

git push --set-upstream origin partner1-branch
  1. Make the following changes on your new branch:
  • Follow the documentation for plt.figtext to add your name as an author on this plot in the bottom right corner.
  1. Push your changes!

Run git pull to make sure you have the most up to date remote changes. Then run git push.

Comprehension check

Where did you just push your changes to? Where do you need to go to check the changes you just made on your remote repository?

Create a pull request!

You now have a branch called main that has the plot you and your partner created. You also have a branch called partner1-branch that has Partner #1’s name as an author. We want to merge the changes from this partner1-branch into our main branch. To do so, we will create a pull request.

  1. Navigate to the remote repository on github.com
  2. Click on the pull request icon
  3. Click “New Pull Request”
  4. In the compare changes tab, merge your branch into the main branch

  1. Click “Create Pull Request”
  2. GitHub will compare your branch with main and make sure there are no conflicts. If there are no conflicts, a “Merge pull request” option will appear. Click on this.
  3. Write a commit message that encompasses the changes you are merging into the main branch
  4. Finally, click “Confirm merge”. You have just merged your branch into main!