Prev: Need help with a program
Next: get error install MySQLdb on Mac OS X
From: Chris Rebert on 28 Jan 2010 15:16
On Thu, Jan 28, 2010 at 11:57 AM, Ray Holt <mrholtsr(a)sbcglobal.net> wrote:
> Why am I getting the following error message. Area has been declared as an
> attribute of Circle. Thanks, Ray
>
> class Circle:
>  def __init__(self):
>      self.radius = 1
>  def area(self):
>      return self.radius * self.radius * 3.14159
>  c = Circle()
>  c.radius = 3
>  print c.area()
>
> Traceback (most recent call last):
>   File "<pyshell#9>", line 1, in <module>
>     class Circle:
>   File "<pyshell#9>", line 8, in Circle
>     print c.area()
> AttributeError: Circle instance has no attribute 'area'

Unable to reproduce:

Python 2.6.4 (r264:75706, Dec 20 2009, 15:52:35)
[GCC 4.2.1 (Apple Inc. build 5646) (dot 1)] on darwin
>>> class Circle:
.... def __init__(self):
.... self.radius = 1
.... def area(self):
.... return self.radius * self.radius * 3.14159
....
>>> c = Circle()
>>> c.radius = 3
>>> print c.area()
28.27431

Cheers,
Chris
--
http://blog.rebertia.com
From: Steve Holden on 28 Jan 2010 15:25
Ray Holt wrote:
> Why am I getting the following error message. Area has been declared as
> an attribute of Circle. Thanks, Ray
>
>
> class Circle:
> def __init__(self):
> self.radius = 1
> def area(self):
> return self.radius * self.radius * 3.14159
> c = Circle()
> c.radius = 3
> print c.area()
>
>
>
> Traceback (most recent call last):
> File "<pyshell#9>", line 1, in <module>
> class Circle:
> File "<pyshell#9>", line 8, in Circle
> print c.area()
> AttributeError: Circle instance has no attribute 'area'
>
Because you have indented the last three lines to make them a part of
the Circle definition. Generally four spaces makes a better indent, and
that kind of problem is then much more obvious.

regards
Steve
--
Steve Holden +1 571 484 6266 +1 800 494 3119
PyCon is coming! Atlanta, Feb 2010 http://us.pycon.org/
Holden Web LLC http://www.holdenweb.com/
UPCOMING EVENTS: http://holdenweb.eventbrite.com/

From: MRAB on 28 Jan 2010 15:33
Ray Holt wrote:
> Why am I getting the following error message. Area has been declared as
> an attribute of Circle. Thanks, Ray
>
>
> class Circle:
> def __init__(self):
> self.radius = 1
> def area(self):
> return self.radius * self.radius * 3.14159
> c = Circle()
> c.radius = 3
> print c.area()
>
>
>
> Traceback (most recent call last):
> File "<pyshell#9>", line 1, in <module>
> class Circle:
> File "<pyshell#9>", line 8, in Circle
> print c.area()
> AttributeError: Circle instance has no attribute 'area'
>
Probably incorrect indentation. This works:

class Circle:
def __init__(self):
self.radius = 1
def area(self):
return self.radius * self.radius * 3.14159
c = Circle()
c.radius = 3
print c.area()
 | 
Pages: 1
Prev: Need help with a program
Next: get error install MySQLdb on Mac OS X