fundamental of python class 11 cbse part 2

PART 2

DATA TYPES

• Data can be of any type like character, integers, real, string,
• Anything enclosed in " " is considered as string in python.
• Any value of fraction part is a real value.
• True or False value specific boolean value.

MUTABLE AND IMMUTABLE

• In python, Data object are categorized in 2 types-

1. Mutable (changeable) - list, dictionary, sets.
2. Immutable (not changeable) - integers, float, boolean, string and tuple.

STRINGS

A string can hold any type of known characters that is no. , letter and special characters.

• Python string stores unicode character.

string is the sequence of character and each character can individually accedes using its index.

forward index starts with 0

backward index starts with -1

In word python 

• name (0)='p'=name(-6)

LIST

• It represent a, separated values of any data type between square brackets [ ]. [1,3,4,].
• List can be changed or modified. That is why list is mutable.

>>> a=[1,2,3,4]

>>> a

     [1,2,3,4]

>>> Print (a)

     [1,2,3,4]

To change 1st value.

>>>a(0)=10

>>>a

      [10,2,3,4] 

TUPLES

• Tuples are also list. It separates values of and type within parentheses.

EXAMPLES

1. p=(1,2,3,4,5,6)
2. f=(1,3,5,7) 

• Values are immutable.

DICTIONARY

• It is an un ordered set. It separates key:value pairs within { }, with the requirement that within a dictionary no 2 key can be the same.

>>> vowels={'a':1,'b':2}