static variables and non-static variables

static variables:

• Any variable which define/declare with in the class and outside the methods, that variables are called static variables or class variables.

• one time memory allocation for static variables.

• the data which is common for multiple objects,that data represents static variables.

• we can access static variables with in the class and out side the class by using class name.

• when ever we call a method, method will be executed.

• how to call the method, by using the object.

class test( ):

    """doc string"""

     x=10     -----> static variable

    def m1(self):   ----> method definition

        print("i am in method1")

t1=test( )    ------> object creation, t1 is ref variable

print(t1.x)   -----> access static variable

t1.m1( )     ------> calling method

print(test.x)   ------> access static variable

10

i am in method1

10

Non- static variables:

• the variables which are declared by using self. are known as non-static variables or instance variables.

• syntax: self .variablename

• the data which is separate for every object is recomonded to the represent using non static variables.

• for all the non-static variables of a class memory will be allocated when ever we create the object.

• with respect to every object creation separate copy of the memory will be allocated for non-static variables of the class.

• non static variables of one class can be accessed in to the all the methods of the same class by using self.

• non static variables of one class can be accessed outside of that class by using reference variable.

• memory allocation for non static variables N no.of times.

class test( ):

    """ doc string"""

    x=1000     ------> static variable

    def m1(self):   -----> method definition

        self.y=10     -----> non static variable

        print(test.x)

        print(self.y)

t1=test( )

t1.m1( )

1000

10

Note:

• There is a relation between non-static variables and objects.

• There is a no relation between static variables and objects.

• automatically memory allocated for static variables.

• automatically memory is not allocated for non static variables.

• allocating the memory for non-static variables at the time object creation.

• accessing the non static variables in side the class by using self.variablename and out side the class by using reference variable.