Data types in Python

Data types: In Python there are following data types mainly used,

1.        Numbers
2.        Strings
3.        Lists
4.        Tuples
5.        Dictionaries

1.  Numbers:

·      Number data type contains the numeric value in it. Number data type created when you assign a numeric value to them.

·        Python supports three types of numerical data types:

o   Int

o   Float

o   Complex numbers

For example:

Integer declaration, var1 = 5

Float declaration, var2 = 9.22

Complex declaration, var3 = 3.14j

In Jupyter Notebook type following to study the number data type. To get output for given statement type Shift + Enter tab.

         

2.      Strings:

·    In Python string can be represented in quotation mark with contiguous set of characters.

·     For example:

str1 = ‘Hello World!!!’

print (str)

·    In Jupyter Notebook type following to study the string data type. To get output for given statement type Shift + Enter tab.

 

          3. Lists:

·      In Python, Lists are most flexible data types that contain items separated by commas and enclosed within the square bracket like [ ].

·        It looks like array but only difference is to store the different data types together.

·        For example:

list1 = ['dnyanesh', 11, 19.5, 'bhavesh']

list2 = [111, 'santosh']

print (list1)                  # It prints complete list

print (list1[0])              # It prints 1st  element of the list

print (list1[1:3])           # It prints elements starting from 2nd  to 3rd element

print (list1[2:])             # It prints elements starting from 3rd  element

print (list2 * 2)            # It prints list two times

print (list1 + list2)       # It prints concatenated lists

This produce following result:

                    4. Tuples:

·    In Python, tuple is look like similar to the list. In tuple values are separated using commas and enclosed within the parenthesis like ( ).

·    The main distinction between lists and tuples is- Lists are enclosed within square brackets [ ] and their values and size can be changed, while tuples are enclosed within parenthesis like ( ) and their values and size cannot be modified.

·      Thus we can say that tuples are read-only list data type.

·       For example:

            tuple1 = ('dnyanesh', 11, 19.5, 'bhavesh')

tuple2 = (111, 'santosh')

print (tuple1)               # It prints complete tuple

print (tuple1[0])           # It prints 1^st  element of the tuple

print (tuple1[1:3])        # It prints elements starting from 2nd  to 3rd ele.

print (tuple1[2:])          # It prints elements starting from 3rd  element

print (list2 * 2)                        # It prints list two times

print (tuple1 + tuple2)             # It prints concatenated lists

This produce following result in Anaconda Jupyter tool:

In following ways tuple shows error message when modification done at tuple value:

tuple1 = ('dnyanesh', 11, 19.5, 'bhavesh')
lis1t = ['dnyanesh', 11, 19.5, 'bhavesh']
tuple[2] = 10               # It is invalid syntax in tuples
list[2] = 10                   # It is valid syntax with lists  

5.      Dictionaries:

·         In Python, dictionaries are work like hash table or an associative array which consists of key with value pairs.

·         Dictionaries can store any python data type in it, but generally it use string and number.

·         The vales are stored in dictionaries using curly bracket i.e. { } and accessed using square bracket i.e. [ ].

·         For example:

d = {'key1':'item1','key2':'item2'}

d['key1']

This produce following result in Anaconda Jupyter tool: