Python Forum

Hi All,
I am new to programming & trying to learn python.
I have created Product class(as Parent) & Inventory (as child) class. How can i use attributes declared in product class in inventory class. In the below example i want to use Product attribute 'pcost' in inventory class.
In Cost function i want to do pcost * pnbr.

Please help.

class Product():
def __init__(self,pname,pid,pcost):
self.pname = pname
self.pid=pid
self.pcost=pcost

class Inventory(Product):
def __init__(self,pnbr,products):
self.pnbr=pnbr
def cost(self):
self.cost=self.pcost*self.pnbr

Pro1=Product('Cookie','01',5)
Pro2=Product('Milk','02',3)

Hi All,
I am new to programming & trying to learn python.
I have created Product class(as Parent) & Inventory (as child) class. How can i use attributes declared in product class in inventory class. In the below example i want to use Product attribute 'pcost' in inventory class.
In Cost function i want to do pcost * pnbr.

class Product():
    def __init__(self,pname,pid,pcost):
        self.pname = pname
        self.pid=pid
        self.pcost=pcost
        
class Inventory(Product):
    def __init__(self,pnbr,products):
        Product.__init__(self,pname,pid,pcost)
        self.pnbr=pnbr
    def cost(self):
        self.cost=self.pcost*self.pnbr

1. Init product need variables define.

class Inventory(Product):
    def __init__(self, pnbr, products)
        Product.__init__(self, "product name", 1, 20)

2. if you want a list of products do not inherit products

class Inventory:
    def __init__(self, pnbr, products)
        self.pnbr = pnbr
        self.products = products

    def cost(self, product_index):
        return self.products[product_index].pcost * self.pnbr

(Nov-16-2017, 03:56 PM)Windspar Wrote: [ -> ]1. Init product need variables define.

The variables will be defined when make instance of the class.

(Nov-16-2017, 03:22 PM)Harry_Potter Wrote: [ -> ]In the below example i want to use Product attribute 'pcost' in inventory class. In Cost function i want to do pcost * pnbr.

class Product(object):
    def __init__(self, pname, pid, pcost):
        self.pname = pname
        self.pid = pid
        self.pcost = pcost

class Inventory(Product):
    def __init__(self, pname, pid, pcost, pnbr, products):
        Product.__init__(self, pname, pid, pcost)
        self.pnbr = pnbr
        self.products = products

    def cost(self):
        self.cost = self.pcost * self.pnbr

Use:

>>> obj = Inventory('Apple', 100, 20, 15, 'foo')
>>> obj.cost()
300
>>> obj.pcost
20
>>> obj.pnbr
15

Python 3 with super().

class Product:
    def __init__(self, pname, pid, pcost):
        self.pname = pname
        self.pid = pid
        self.pcost = pcost

class Inventory(Product):
    def __init__(self, pname, pid, pcost, pnbr, products):        
        super().__init__(pname, pid, pcost)
        self.pnbr = pnbr
        self.products = products

    def cost(self):
        self.cost = self.pcost * self.pnbr
        return self.cost