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→List
=== Collections ===
=== Collections ===
==== List ====
==== List ====
Collection - allows us to put many values in a single variable.
Simple variables are not collections. The previous value is overwritten when changed.
* A List is made up of list 'constants'. Lists are surrounded by square brackets [] and the constants in the list are separated by commas. ([2,4,6,8])
* A List element can be any Python object, even another list
* A List can be empty
* Lists are mutable (they can be changed)
* When len() is used on a list, it counts the number of constants that make up the list. (not the number of characters)
* Lists can be concatenated using +
* Lists can be sliced
* List is a unique type that can be checked using type() (result: <type 'list'>)
* An empty list can be created with list()
* Lists can be tested for contents using in/not in
* List is an ordered sequence
* A list can be sorted with .sort(). Sort changes the list permanently.
* sorted(list) → Returns a list sorted.
* sorted(list) → Returns a list sorted.
* Methods: append, count, extend, index, insert, pop, remove, reverse, sort
* Functions len() - find length, max() - find highest value, min() - find lowest value, sum() - add all values average can be found with sum()/len()
==== Tuple ====
==== Tuple ====