--- Kent Johnson <[EMAIL PROTECTED]> wrote: > Hoffmann wrote: > > We are almost there. I changed the code and, at > least, > > I got the correct output. However, I also got a > > traceback. I didn't understand the traceback. > Could > > you clarify that? > > Thanks, > > Hoffmann > > ps: The new code: > > > > > >>>>vehicle='car' > >>>>index = -1 #index of the last letter > >>>>lenght = len(vehicle) > >>>>last = vehicle[lenght-1] > >>>> > >>>>while last >= vehicle[0]: > > > > letter=vehicle[index] > > print letter > > index -= 1 > > You are still confusing the index of a letter and > the letter itself. > > In [1]: vehicle = 'car' > > In [2]: last = vehicle[-1] > > In [3]: last > Out[3]: 'r' > > last is a letter, not a number. > > In [5]: vehicle[0] > Out[5]: 'c' > > vehicle[0] is also a letter. So when you write > while last >= vehicle[0]: > you are comparing two characters, which is not > really helpful in the > current context. What you really want to do is > compare the index of the > current character with 0. Here is a working version > in the same style: > > In [6]: index = len(vehicle)-1 > > In [7]: while index >= 0: > ...: print vehicle[index] > ...: index -= 1 > ...: > ...: > r > a > c > > The best way to reverse a string is with a slice and > negative index: > > In [8]: vehicle[::-1] > Out[8]: 'rac' > > but I'm going to have to leave explanation of that > to another day or > another poster. > > Kent > > > _______________________________________________
Hello Guys, Thank you very much all of you (in special: Kent, John, and Adam), for the nice explanations about my excercise. I am a newbie that is studying Python programming by myself. I appreciated your attention. See you on my next post :-) Best, Hoffmann __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
