In python variable is created as in following example
Rules for variable names:
1. It should start wih either a letter or the underscore character.
2. Variable cannot start with a number.
3. Can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
4. Uppercase and lowercase names are treated differently.
Python has five standard data types −
A list contains items separated by commas and enclosed within square brackets []. To some extent, lists are similar to arrays in C. One difference between them is that all the items belonging to a list can be of different data type.
Example:
Tuples are kind of lists except that they are read only. They are enclosed by using paranthesis instead of square brackets(for lists). While lists can be updated tuples cannot be updated.
Example:
Dictionary:
In Python's dictionaries are kind of hash table. They work like hashes in Perl and consist of key-value pairs. Dictionaries are enclosed by curly braces { } and values can be assigned and accessed using square braces [].
Example :
References:
https://www.tutorialspoint.com/python/python_variable_types.htm
https://www.w3schools.com/python/python_variables.asp
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| x = 5
y = "John"
print(x)
print(y)
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Rules for variable names:
1. It should start wih either a letter or the underscore character.
2. Variable cannot start with a number.
3. Can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
4. Uppercase and lowercase names are treated differently.
Python has five standard data types −
- Numbers
- String
- List
- Tuple
- Dictionary
A list contains items separated by commas and enclosed within square brackets []. To some extent, lists are similar to arrays in C. One difference between them is that all the items belonging to a list can be of different data type.
Example:
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| #!/usr/bin/python
mylist = [ 'abcd', 786 , 2.23, 'john', 70.2 ]
smalllist = [123, 'john']
print mylist # Prints complete list
print mylist[0] # Prints first element of the list
print mylist[1:3] # Prints elements starting from 2nd till 3rd
print mylist[2:] # Prints elements starting from 3rd element
print smalllist * 2 # Prints list two times
print mylist + smalllist # Prints concatenated lists
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Tuples are kind of lists except that they are read only. They are enclosed by using paranthesis instead of square brackets(for lists). While lists can be updated tuples cannot be updated.
Example:
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| #!/usr/bin/python
mytuple = ( 'abcd', 786 , 2.23, 'john', 70.2 )
smalltuple = (123, 'john')
print tuple # Prints complete tuple
print tuple[0] # Prints first element of the tuple
print tuple[1:3] # Prints elements starting from 2nd till 3rd
print tuple[2:] # Prints elements starting from 3rd element
print smalltuple * 2 # Prints tuple two times
print tuple + smalltuple # Prints concatenated tuples
|
Dictionary:
In Python's dictionaries are kind of hash table. They work like hashes in Perl and consist of key-value pairs. Dictionaries are enclosed by curly braces { } and values can be assigned and accessed using square braces [].
Example :
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| #!/usr/bin/python
dict = {}
dict['one'] = "This is one"
dict[2] = "This is two"
dicts = {'name': 'john','code':6734, 'dept': 'sales'}
print dict['one'] # Prints value for 'one' key
print dict[2] # Prints value for 2 key
print dicts # Prints complete dictionary
print dicts.keys() # Prints all the keys
print dicts.values() # Prints all the values
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References:
https://www.tutorialspoint.com/python/python_variable_types.htm
https://www.w3schools.com/python/python_variables.asp
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