Typecasting in Python

 

Python Typecasting

int() : converts string to integer.

 #program to typecast user provided data to integer

 age= input("Enter age in years : ")
 print("age :",age,"and type(age) :",type(age))
 age= int(age);                      #typecasting
 print("after typecast\nage :",age,"and type(age) :",type(age))


 #output
 Enter age in years : 28
 age : 28 and type(age) : <class 'str'>
 after typecast
 age : 28 and type(age) : <class 'int'>

Limitation:

to typecast user input data to integer, all provided data should be numbers, it should neither contains character nor '.' , it should be with base 10. 

 #output

 case 1 :
 Enter age in years : twenty Eight
 age : twenty Eight and type(age) : <class 'str'>
 Traceback (most recent call last):
   File "C:/Self_Practice_Er_M_S_Dandyan/Python/Pycharm/xml/main.py", line 5, in <module>
     age= int(age);                      #typecasting
 ValueError: invalid literal for int() with base 10: 'twenty Eight'

 Case 2:
 Enter age in years : 28.6
 age : 28.6 and type(age) : <class 'str'>
 Traceback (most recent call last):
   File "C:/Self_Practice_Er_M_S_Dandyan/Python/Pycharm/xml/main.py", line 5, in <module>
     age= int(age);                      #typecasting
 ValueError: invalid literal for int() with base 10: '28.6'

float() : converts string to float.

 #program to typecast user provided data to float

 mark= input("Enter mark in %: ")
 print("mark :",mark,"and type(mark) :",type(mark))
 mark= float(mark);
 print("after typecast\nmark :",mark,"and type(mark) :",type(mark))


 #output
 mark= input(“Enter mark in %: ”)
 print(“mark :”,mark,”and type(mark) :”,type(mark))
 mark= float(mark);
 print(“after typecast\nmark :”,mark,”and type(mark) :”,type(mark))

Limitation :

 #program to typecast user provided data to integer

 mark= input("Enter mark in %: ")
 print("mark :",mark,"and type(mark) :",type(mark))
 mark= float(mark);
 print("after typecast\nmark :",mark,"and type(mark) :",type(mark))


 #output
 Enter mark in %: eighty.seven two
 mark : eighty.seven two and type(mark) : <class 'str'>
 Traceback (most recent call last):
   File "C:/Self_Practice_Er_M_S_Dandyan/Python/Pycharm/xml/main.py", line 5, in <module>
     mark= float(mark);
 ValueError: could not convert string to float: 'eighty.seven two'

to typecast user input to float, all provided data should be numbers and should not contain characters

Other way of doing typecasting

we can typecast data at the time of collection itself.

 #program to typecast user provided data
 age= int(input("Enter age in years : "))
 mark= float(input("Enter mark in %: "))
 print("age :",age,"and type(age) :",type(age))
 print("mark :",mark,"and type(mark) :",type(mark))


 #output
 Enter age in years : 28
 Enter mark in %: 80.72
 age : 28 and type(age) : <class 'int'>
 mark : 80.72 and type(mark) : <class 'float'>