# [Tutor] next class problem

bob gailer bgailer at gmail.com
Sat Sep 18 19:40:55 CEST 2010

```  On 9/18/2010 1:20 PM, Roelof Wobben wrote:
>
> Hello,
>
> I have this exercise :
>
> Rewrite the distance function from chapter 5 so that it takes two Points as parameters instead of four numbers.
>
> I have this solution :
>
> class Point:
>       def __init__(self, x=0, y=0):
>           self.x = x
>           self.y = y
>
> def distance(p1,p2):
>      dx = p2.x - p1.x
>      dy = p2.y - p1.y
>      dsquared = dx**2 + dy**2
>      result = dsquared**0.5
>      return result
> P1 = Point()
> P1.x = 3
> P1.y = 3
> P2 = Point()
> P2.x = 6
> P2.y = 7
> result = distance (P1,P2)
> print result
>
>
> Is this the correct solution ?

What is your criteria for "correct"?

There is no one correct solution!

You seem to be passing 2 points, as requested.

Do you get the correct answer?

Then it mus be correct.

FWIW Python convention recommends names starting with lower case except
for classes and constants.

Therefore p1 and p2 are preferred to P1 and P2.

Also why not initialize x and y thus:
p1 = Point(3,3)
That is what the __init__ is for.

--
Bob Gailer
919-636-4239
Chapel Hill NC

```