Python Coding Interview Questions
A Namespace in Python is a mapping between a name and an object. It is currently implemented as Python dictionary.
E.g. the set of built-in exception names, the set of built-in names, local names in a function
At different moments in Python, different Namespaces are created. Each Namespace in Python can have a different lifetime.
For the list of built-in names, Namespace is created when Python interpreter starts.
When Python interpreter reads the definition of a module, it creates a global namespace for that module.
When Python interpreter calls a function, it creates a local namespace for that function.
E.g. the set of built-in exception names, the set of built-in names, local names in a function
At different moments in Python, different Namespaces are created. Each Namespace in Python can have a different lifetime.
For the list of built-in names, Namespace is created when Python interpreter starts.
When Python interpreter reads the definition of a module, it creates a global namespace for that module.
When Python interpreter calls a function, it creates a local namespace for that function.
Some of the built-in data types available in Python are as follows:
Numeric types: These are the data types used to represent numbers in Python.
int: It is used for Integers
long: It is used for very large integers of non-limited length.
float: It is used for decimal numbers.
complex: This one is for representing complex numbers
Sequence types: These data types are used to represent a sequence of characters or objects.
str: This is similar to String in Java. It can represent a sequence of characters.
bytes: This is a sequence of integers in the range of 0-255.
byte array: like bytes, but mutable (see below); only available in Python 3.x
list: This is a sequence of objects.
tuple: This is a sequence of immutable objects.
Sets: These are unordered collections.
set: This is a collection of unique objects.
frozen set: This is a collection of unique immutable objects.
Mappings: This is similar to a Map in Java.
dict: This is also called hashmap. It has key-value pair to store information by using hashing.
Numeric types: These are the data types used to represent numbers in Python.
int: It is used for Integers
long: It is used for very large integers of non-limited length.
float: It is used for decimal numbers.
complex: This one is for representing complex numbers
Sequence types: These data types are used to represent a sequence of characters or objects.
str: This is similar to String in Java. It can represent a sequence of characters.
bytes: This is a sequence of integers in the range of 0-255.
byte array: like bytes, but mutable (see below); only available in Python 3.x
list: This is a sequence of objects.
tuple: This is a sequence of immutable objects.
Sets: These are unordered collections.
set: This is a collection of unique objects.
frozen set: This is a collection of unique immutable objects.
Mappings: This is similar to a Map in Java.
dict: This is also called hashmap. It has key-value pair to store information by using hashing.
Main differences between List and Dictionary data types in Python are as follows:
1. Syntax: In a List, we store objects in a sequence. In a Dictionary, we store objects in key-value pairs.
2. Reference: In List, we access objects by index number. It starts at 0 indexes. In a Dictionary we access objects by key specified at the time of Dictionary creation.
3. Ordering: In a List, objects are stored in an ordered sequence. In a Dictionary objects are not stored in an ordered sequence.
4.Hashing: In a Dictionary, keys have to be hashable. In a List, there is no need for hashing.
*/?>
*/?>
*/?>
*/?>