From eaf9aa752f40bfc4d7dafcffd2d7f8b057d2fa36 Mon Sep 17 00:00:00 2001 From: David Rotermund <54365609+davrot@users.noreply.github.com> Date: Mon, 11 Dec 2023 09:53:44 +0100 Subject: [PATCH] Create README.md Signed-off-by: David Rotermund <54365609+davrot@users.noreply.github.com> --- python_basics/list/README.md | 143 +++++++++++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) create mode 100644 python_basics/list/README.md diff --git a/python_basics/list/README.md b/python_basics/list/README.md new file mode 100644 index 0000000..92eb13b --- /dev/null +++ b/python_basics/list/README.md @@ -0,0 +1,143 @@ +# Sequence Types: list +{:.no_toc} + + + +## The goal + +> Lists are **mutable** sequences, **typically** used to store collections of **homogeneous** items (where the precise degree of similarity will vary by application).​ + +[Quote](https://docs.python.org/3/library/stdtypes.html#lists) + +Questions to [David Rotermund](mailto:davrot@uni-bremen.de) + +## Example Lists + +With homogeneous items: + +```python +primes = [2, 3, 5, 7] + +collection_of_strings = [ + "AA", + "BB", + "CC", + "DD", + "EE", + "FF", + "GG", + "HH", +] +``` + +A mixture of type: + +```python +def my_function(a): + return a + +my_favourite_things = [32, "sleep", my_function] +``` + +## Indexing + +```python +collection_of_strings = [ + "AA", + "BB", + "CC", + "DD", + "EE", + "FF", + "GG", + "HH", +] + + +print(collection_of_strings[0]) # -> AA +print(collection_of_strings[1]) # -> BB +print(collection_of_strings[-2]) # -> GG +print(collection_of_strings[-1]) # -> HH +``` + +## Slicing + +```python +collection_of_strings = [ + "AA", + "BB", + "CC", + "DD", + "EE", + "FF", + "GG", + "HH", +] + + +print(collection_of_strings[0:3]) # -> ['AA', 'BB', 'CC'] +print(collection_of_strings[:3]) # -> ['AA', 'BB', 'CC'] +print(collection_of_strings[3:]) # -> ['DD', 'EE', 'FF', 'GG', 'HH'] +print(collection_of_strings[1:-1]) # -> ['BB', 'CC', 'DD', 'EE', 'FF', 'GG'] +print(collection_of_strings[-3:]) # -> ['FF', 'GG', 'HH'] +``` + +## Changing lists + +```python +collection_of_strings = [ + "AA", + "BB", + "CC", + "DD", + "EE", + "FF", + "GG", + "HH", +] + +collection_of_strings[3] = "II" +print(collection_of_strings) # -> ['AA', 'BB', 'CC', 'II', 'EE', 'FF', 'GG', 'HH'] +collection_of_strings[:3] = ["JJ", "KK", "LL"] +print(collection_of_strings) # -> ['JJ', 'KK', 'LL', 'II', 'EE', 'FF', 'GG', 'HH'] +collection_of_strings[:4] = [ + "MM", + "NN", + "OO", + "PP", +] +print(collection_of_strings) # -> ['MM', 'NN', 'OO', 'PP', 'EE', 'FF', 'GG', 'HH'] +``` + +## List functions + +# [len()](https://docs.python.org/3/library/functions.html#len) and [sorted()](https://docs.python.org/3/library/functions.html#sorted) + + +```python +collection_of_strings = [ + "GG", + "HH", + "AA", + "BB", + "EE", + "FF", + "CC", + "DD", +] + + +print(len(collection_of_strings)) # -> 8 +print(sorted(collection_of_strings)) # -> ['AA', 'BB', 'CC', 'DD', 'EE', 'FF', 'GG', 'HH'] +``` + +### [max()](https://docs.python.org/3/library/functions.html#max) and [sum()](https://docs.python.org/3/library/functions.html#sum) + +```python +primes = [2, 3, 5, 7] +print(sum(primes)) # -> 17 +print(max(primes)) # -> 7 +```