How can I call a function within a class?

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Problem :

I have this code which calculates the distance between two coordinates. The two functions are both within the same class.

However, how do I call the function distToPoint in the function isNear?

class Coordinates:
    def distToPoint(self, p):
        """
        Use pythagoras to find distance
        (a^2 = b^2 + c^2)
        """
        ...

    def isNear(self, p):
        distToPoint(self, p)
        ...

Solution :

Since these are member functions, call it as a member function on the instance, self.

def isNear(self, p):
    self.distToPoint(p)
    ...

That doesn’t work because distToPoint is inside your class, so you need to prefix it with the classname if you want to refer to it, like this: classname.distToPoint(self, p). You shouldn’t do it like that, though. A better way to do it is to refer to the method directly through the class instance (which is the first argument of a class method), like so: self.distToPoint(p).

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