General

Available Resources

eBook: DS and IR in Python For learning: - Basic Python Syntax, Essential Frameworks and Libraries, and Data Structures and Algorithms.

Python Collections

Iterable

Anything that you can loop over using a for loop e.g: list, tuples, strings, set and dictionaries

Sequence

a subset of Iterables that have: 1. A length 2. An Index 3. Can be sliced

e.g: Strings, list, tuples

Not dictionaries, sets, files and generators

Data Structures

Python supports the following data structures: lists, dictionaries, tuples, sets. For arrays, see array or numpy array.

When to use a dictionary: - When you need a logical association between a key:value pair. - When you need fast lookup for your data, based on a custom key. - When your data is being constantly modified. Remember, dictionaries are mutable.

When to use the other types: - Use lists if you have a collection of data that does not need random access. Try to choose lists when you need a simple, iterable collection that is modified frequently. - Use a set if you need uniqueness for the elements. - Use tuples when your data cannot change.

Many times, a tuple is used in combination with a dictionary, for example, a tuple might represent a key, because it's immutable.

Tuples	Lists	Dict	Sets
( )	[ ]	{k:v}	{ }
Immutable	Mutable	Mutable	Mutable
Ordered	Ordered	Ordered(>3.7)	Unordered
Iterable	Iterable	Iterable	Iterable
Constant time	Linear time	Constant time	Constant time
mytuple[0]	mylist[0]	mydict['somekey']	myset[0]
Allow repetition	Allow repetition	Allow repetition	Unique data
len(mytuple)	len(mylist)	len(mydict)	len(myset)
.count()	.append() and .insert()	.keys(), .values() and .items()	.add() and .update()
.index()	.pop() and .remove()	.pop() or del mydict['somekey']	.remove()
	.reverse() and sort()