#set document(title: "3.6 Chapter summary", author: "OpenStax / XYZ Homework")
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== 3.6#h(0.6em)Chapter summary


  Highlights from this chapter include:


  - A #strong[string] is a sequence of values that represents Unicode code points.
- An #strong[index] refers to the position of a value in a sequence (string, list, tuple).
- Positive indexes range from 0 to length–1. Negative indexes range from –1 to –length.
- F-strings are a convenient way to print multiple outputs and format integers and floats.
- Variables refer to objects. Memory diagrams are useful for drawing variables and objects.
- A list object can be used to refer to multiple objects, by index, using the same variable.
- A tuple is similar to a list, but uses parentheses and cannot be changed once created.


  #figure(table(
  columns: 2, align: left, inset: 6pt,
  table.header([Code], [Description]),
  [ord(c)], [Gets an integer representing the Unicode code point of a character.],
  [chr(i)], [Converts a Unicode code point (integer) into a One-character string.],
  ['\\n'], [Escape sequence for the newline character.],
  ['\\t'], [Escape sequence for the tab character.],
  [f"{number:.02d}"], [Creates a string by formatting an integer to be at least two digits.],
  [f"{number:.2f}"], [Creates a string by formatting a float to have two decimal places.],
  [id(object)], [Gets the identity (memory location) of an object.],
  [type(object)], [Gets the type (class name) of an object.],
  [my\_list = \["a", "b", "c"\]], [Creates a list of three strings.],
  [my\_tuple = ("a", "b", "c")], [Creates a tuple of three strings.],
  [my\_list\[0\]], [Gets the first element ("a") of my\_tuple.],
  [my\_tuple\[-1\]], [Gets the last element ("c") of my\_tuple.],
))