Family Tree

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.8.0", override: true},
  {:youtube, github: "brooklinjazz/youtube"},
  {:hidden_cell, github: "brooklinjazz/hidden_cell"}
])

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Family Tree

Maps allow you to create tree like structures using keys and values. Thus it’s possible to make a family tree. In the Elixir cell below, create a family tree that is a map.

flowchart BT
p1g1[Grandparent]
p1g2[Grandparent]
p2g1[Grandparent]
p2g2[Grandparent]
p1[Parent]
p2[Parent]
c1[Child]

c1 --> p1
c1 --> p2
p1 --> p1g1
p1 --> p1g2
p2 --> p2g1
p2 --> p2g2

The map will start as a person with a :name, :age, :status, and :parents keys.

• name is string.
• age is an integer.
• status will be an atom of :child, :parent, or :grandparent.
• parents should be a list of maps with their own :name, :age, :status, and :parents keys.

In the Elixir cell below, create a map that represents the following family tree diagram.

classDiagram
    direction BT
    class Arthur {
        name: "Arthur"
        status: :child
        age: 22
    }
    class Uther {
        name: "Uther"
        status: :parent
        age: 56
    }
    class Ygraine {
        name: "Ygraine"
        status: :parent
        age: 45
    }
    class Han {
        name: "Han"
        status: :grand_parent
        age: 81
    }
    class Leia {
        name: "Leia"
        status: :grand_parent
        age: 82
    }
    class Bob {
        name: "Bob"
        status: :grand_parent
        age: 68
    }
    class Bridget {
        name: "Bridget"
        status: :grand_parent
        age: 70
    }

    Arthur --> Uther
    Arthur --> Ygraine
    Ygraine --> Bob
    Ygraine --> Bridget
    Uther --> Han
    Uther --> Leia

Example solution

This is an example of nested data.

%{
  name: "Arthur",
  status: :child,
  age: 22,
  parents: [
    %{
      name: "Uther",
      status: :parent,
      age: 56,
      parents: [
        %{name: "Han", status: :grand_parent, age: 81},
        %{name: "Leia", status: :grand_parent, age: 82}
      ]
    },
    %{
      name: "Ygraine",
      status: :parent,
      age: 68,
      parents: [
        %{name: "Bob", status: :grand_parent, age: 68},
        %{name: "Bridget", status: :grand_parent, age: 70}
      ]
    }
  ]
}

You might also consider extracting each family member as its own variable.

han = %{name: "Han", status: :grand_parent, age: 81}
leia = %{name: "Leia", status: :grand_parent, age: 82}
bob = %{name: "Bob", status: :grand_parent, age: 68}
bridget = %{name: "Bridget", status: :grand_parent, age: 70}

uther = %{name: "Uther", status: :parent, age: 56, parents: [han, leia]}
ygraine = %{name: "Ygraine", status: :parent, age: 68, parents: [bob, bridget]}

arthur = %{name: "Arthur", status: :child, age: 22, parents: [uther, ygraine]}

family_tree = arthur

Enter your solution below.

Mark As Completed

file_name = Path.basename(Regex.replace(~r/#.+/, __ENV__.file, ""), ".livemd")

save_name =
  case Path.basename(__DIR__) do
    "reading" -> "family_tree_reading"
    "exercises" -> "family_tree_exercise"
  end

progress_path = __DIR__ <> "/../progress.json"
existing_progress = File.read!(progress_path) |> Jason.decode!()

default = Map.get(existing_progress, save_name, false)

form =
  Kino.Control.form(
    [
      completed: input = Kino.Input.checkbox("Mark As Completed", default: default)
    ],
    report_changes: true
  )

Task.async(fn ->
  for %{data: %{completed: completed}} <- Kino.Control.stream(form) do
    File.write!(
      progress_path,
      Jason.encode!(Map.put(existing_progress, save_name, completed), pretty: true)
    )
  end
end)

form

Commit Your Progress

Run the following in your command line from the curriculum folder to track and save your progress in a Git commit. Ensure that you do not already have undesired or unrelated changes by running git status or by checking the source control tab in Visual Studio Code.

$ git checkout -b family-tree-exercise
$ git add .
$ git commit -m "finish family tree exercise"
$ git push origin family-tree-exercise

Create a pull request from your family-tree-exercise branch to your solutions branch. Please do not create a pull request to the DockYard Academy repository as this will spam our PR tracker.

DockYard Academy Students Only:

Notify your teacher by including @BrooklinJazz in your PR description to get feedback. You (or your teacher) may merge your PR into your solutions branch after review.

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