₦airaland Forum

I'm new to programming and I'm trying to write a python program to help me with a problem that I am facing and I got stuck at trying to solve a problem similar to the one below. I recreated the error using a mock example.

import numpy as np

class test:

def __init__(self, length, width):
self.length = length
self.width = width

def area(self):
self.length = length
self.width = width

area = self.length * self.width

return area

def area_2(self):
return np.square(test.area())

rect = test(9,9)
When I run

rect.area_2()
I get the following error:

TypeError: area() missing 1 required positional argument: 'self'
why doesn't this work?

# this line is the cause of the error.

return np.square(test.area())

I assume you are trying to call the area method from area_2 method.

Fix:
use the keyword self instead of the class name :

return np.square(self.area())