[Tutor] Odd result from function call

[Vince Spicer]

On Fri, Jan 7, 2011 at 11:38 AM, Ben Ganzfried <ben.ganzfried at gmail.com>wrote:

> When I call one of my functions from the shell (ie compare(10, 5)) it
> produces the correct output.  However, when I run the program after calling
> the method later in the script, the result is bizarre.  I'm curious why the
> wrong result is printed.  Here is an example:
>
> def compare(x,y):
>     if x < y:
>         print (x, " is less than ", y)
>         print("x is ", x, "y is ", y)
>     elif x > y:
>         print(x, " is greater than ", y)
>     else:
>         print(x, " and ", y, " are equal.")
>
>
> x = input("First x is: ")
> y = input("First y is: ")
> print("x is ", x)
> print("y is ", y)
> compare(x,y)
> a = input("Second x is: ")
> b = input("Second y is: ")
> print("x is ", a)
> print("y is ", b)
> compare(a,b)
> c = input("Third x is: ")
> d = input("Third y is: ")
> print("x is ", c)
> print("y is ", d)
> compare(c,d)
>
> Sample (and incorrect) output w/ 10, 5:
>
> First x is: 10
> First y is: 5
> x is  10
> y is  5
> 10  is less than  5
> x is  10 y is  5
> Second x is:
>
> When I do simply compare(10, 5) from the shell, I get the correct output
> (ie 10 is greater than 5).  I had thought I had narrowed the problem down to
> the fact that when I run the script only the first digit is counted--
> however, it seems as if only the first digit is counted (ie anything
> starting w/ a 9 will be greater than anything starting with a 1 (even if the
> numbers are 9 and 1324234)), and THEN, the second digit is counted (such
> that 89 is correctly identified at 81).
>
> Anyway I'm wondering:
> 1) Why does the script run correctly when I simply call the function from
> the shell but not when I try to call the function from within the script?
> 2) What is actually going on such that only the first digit is being
> evaluated?  That is, the interpreter knows that x is 10 and y is 5-- and
> yet, for some reason the 5 is being tested against the 1 and since 5 is
> bigger than 1, it concludes that 5 is greater than 10.
>
> thanks!
>
> Ben
>
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>
Ben

It would appear that you are comparing string in your script and not
integers

a=  int(input(.......))

-- 
Vince Spicer
Developer
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