[Tutor] bubble sort function

Alan Gauld alan.gauld at btinternet.com
Wed Nov 26 14:42:00 CET 2014

On 26/11/14 11:16, Sunil Tech wrote:

> Thank you Alan. But a question here, how would it understand that the 
> given input is valid?

That's what the bit inside the loop does.
It checks whether the input string is a digit (specifically a decimal 
If it is a digit it returns the result as an integer
otherwise it spits out an error and goes round the loop again.

PS Please don't top post. This thread is already getting hard to follow 
only 2 exchanges!

> On Mon, Nov 17, 2014 at 9:57 AM, Danny Yoo <dyoo at hashcollision.org 
> <mailto:dyoo at hashcollision.org>
>         <mailto:dyoo at hashcollision.org
>         <mailto:dyoo at hashcollision.org>>> wrote:
>             > def ask_for_a_digit():
>             >     while True:
>             >         digit = raw_input("Give me a digit between 0 and
>         9.")
>             >         if digit not in "0123456789":
>             >             print "You didn't give me a digit. Try again."
>             >         else:
>             >             return int(digit)
>     The while loop makes it keep on asking until a valid input is
>     received. Without the while loop it would only ask once and
>     either return None or a digit.
>     HTH
Alan G
Author of the Learn to Program web site
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