Python Forum

Please i need help, this code does not compute the area

# An object-oriented programming style to calculate area of triangle (1/2 base times height)

import sys
import math
a = input("Enter the value of the first side:")
b = input("Enter the value of the second side:")
c = input("Enter the value of the third side:")
class triangle():
   def __init__(self,a,b,c):
       self.a = a
       self.b = b
       self.c = c
   def area(a, b, c):
       s=(a + b + c)/2
       area=math.sqrt(s*(s-a)*(s-b)*(s-c))
       return area
print (area((a,b,c)))

---

------this is the output

Error:
Enter the value of the first side:4
Enter the value of the second side:5
Enter the value of the third side:6
Traceback (most recent call last):
  File "area2.py", line 17, in <module>
    print (area((a,b,c)))
NameError: name 'area' is not defined

Your code is trying to use a global function area(), which doesn't exist.

area() is a method of a triangle object, it should take no arguments (except self), and should be used like so:

t = triangle(a, b, c)
print(t.area())

You'll also need to convert your inputs to numbers (using int() or float()), since input() returns strings on python 3.

Please can u explain further, at what lines should i make the corrections.

i have done this:

import sys
import math
a = 5
b = 6
c = 7
class triangle():
   def __init__(self,a,b,c):
       self.a = a
       self.b = b
       self.c = c
   def area(a, b, c):
       s=(a + b + c)/2
       area=math.sqrt(s*(s-a)*(s-b)*(s-c))
       return area
t = triangle(a, b, c)
print(t.area())

but it displays this error:

Error:
 print(t.area())
eError: area() missing 2 required positional arguments: 'b' and 'c'

__________________-This code finally worked, thanks for helping me learn the hard way.

import sys
import math

a = int(input('Please enter the first side of a triangle: '))
b = int(input('Please enter the second side of a triangle: '))
c = int(input('Please enter the third side of a triangle: '))
class triangle():
   def __init__(self,a,b,c):
       self.a = a
       self.b = b
       self.c = c
   def area(self):
       s=(a + b + c)/2
       area=math.sqrt(s*(s-a)*(s-b)*(s-c))
       return area
t = triangle(a, b, c)
print(t.area())

_____Output

Output:
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Users\TOPEV\Documents\School\Programming Language>python area2.py
Please enter the first side of a triangle: 2
Please enter the second side of a triangle: 3
Please enter the third side of a triangle: 3
2.8284271247461903