Values and Types

• A value is a basic think that a program work with, like a letter or a number. Eg: 1,2 and ‘hello world’
• The values belongs to different types. In python the standard data types available are:

1. Numbers
2. Strings
3. List
4. Tuples
5. dictionary

Numbers

Numbers data type stores numerical values. It supports four numerical types.

1. int (singed numbers like 10, -2)
2. long (long intrgers represented in octal and hexadecimal)
3. float (floating point like 3.14)
4. Complex (comlex number like x = 4+5j )

String data type

• String are the sequence of characters represented with in quotation marks.
• It allows either pairs of single or double quotes. The substring access is possible through the slicing operator ([] or [:])

The string index 0 represents beginning of the string.

                 index -1 represent ending of the string.

Example:

str='Hello World'

Code	Result	Definition
str	Hello World	#print complete string
str[0]	H	#print the first character of the string
str[-1]	d	#print the last character of the string
str[1:5]	ello	#print character starting from index 1 to 4
str[2:]	llo World	#print string starting at index 2 till tha end of the string
str*2	Hello WorldHello World	#print string repeatedly two times
str+" hai"	Hello World hai	#print concatenated string

List data type

• List are the most significant compound data type contain element of various types
• A list can hold items of different data types it is enclosed by square brackets []. Where the items are separated by commas
• It is similar to string accessed  using slice operator ([] or [:])

The sting index 0 represents the beginning of the list.

         index 1 represents the ending of the list.

Example

List1 = ['abcd', 345, 3.2, 'python', 3.14]

List2 = [234, 'xyz']

Code	Result	Definition
List1	['abcd', 345, 3.2, 'python', 3.14]	#print complete list
List1[0]	abcd	#print the first character of the list
List1[-1]	3.14	#print the last character of the List
List1[1:2]	[245, 3.2]	#print character starting from index 1 to 2
List1[2:]	[3.2, 'python', 3.14]	#print string starting at index 2 till tha end of the list
List2*2	[234, 'xyz', 234, 'xyz']	#print list repeatedly two times
List1+List2	['abcd', 345, 3.2, 'python', 3.14, 234, 'xyz']	#print concatenated lists

Tuple data type

• Tuple is another sequence data type similar to list
• A tuple consists of number of values separated by cammas and enclosed with parentheses
• Tuple value cannot be updated.

Example

Tuple1 = ('abcd', 345, 3.2, 'python', 3.14)

Tuple2 = (234, 'xyz')

Code	Result	Definition
Tuple1	('abcd', 345, 3.2, 'python', 3.14)	#print complete Tuple
Tuple1[0]	abcd	#print the first character of the Tuple
Tuple1[-1]	3.14	#print the last character of the Tuple
Tuple1[1:2]	(245, 3.2)	#print character starting from index 1 to 2
Tuple1[2:]	(3.2, 'python', 3.14)	#print string starting at index 2 till tha end of the Tuple
Tuple2*2	(234, 'xyz', 234, 'xyz')	#print Tuple repeatedly two times
Tuple1+Tuple2	('abcd', 345, 3.2, 'python', 3.14, 234, 'xyz')	#print concatenated Tuples

Dictionary data type

• Dictionary data type is a kind of hash table.
• It contain key-value pairs almost any python type usually numbers or string.
• Dictionaries are enclosed by curly braces {} and values can be assigned and accessed using square brackets []. 

Example

Dict1={'name':'abcd', 'code':9530, 'dept':'Mech'}

Code	Result	Definition
Dict1	{'name':'abcd', 'code':9530, 'dept':'Mech'}	#print complete dictionary
Dict1['name']	abcd	#print the value for the key

Boolean data type

• Boolean is one more datatype supported in python. It takes values: True or False.

Eg: print True

      print False