Error in following code

[Efrat Regev]

zaperaj at gmail.com wrote:
> Im working with python2.2 on red hat linux.
> The following program is supposed to print decreasing numbers from an
> entered number till 1, each decrement being = 1 :
> 
> #! usr/bin/env/python
> 
> def f(n=int(raw_input("enter number: "))):
>      print 'n=',n
>      if n>1:
>              return n*f(n-1)
>      else:
>              print 'end'
> 	     return 1
> 
> 
> 
> 
> Though it works fine on the python interpretor, i dont get the
> required output when i write this code in gedit (text editor). The
> output that i get is (where t4.py is the name of the file):
> 
> [root at localhost root]# python t4.py
> enter number: 6
> [root at localhost root]#
> 
> i.e it takes the input but doesn't print anything. If anybody can
> help... Thanx!
> 

	Hello,

	When you run it through the interpreter, then the interpreter "looks" 
at your definition of f, "understands" it, and continues on. What 
follows your definition of f? Nothing. In particular, nothing instructs 
the interpreter to *execute* f. So your problem is not that f is being 
executed but is not printing anything, but rather that f is not being 
executed.


	To do what you want it to do, maybe try the following:
#! usr/bin/env/python

def f(n):
      print 'n=',n
      if n>1:
              return n*f(n-1)
      else:
              print 'end'
	     return 1


if __name__ == '__main__':
	n = int(raw_input("enter number: "))

	f(n)


	The line (if __name__...) means that if the interpreter is running your 
module the way you mean here, then it should get the raw input for n, 
then call f.

	HTH,

	Efrat

P.S. Note that I changed your f so that it doesn't do input itself. 
Coupling calculation code with user-interaction code is maybe not so 
good (IMHO).