[Tutor] ValueError

[Corey Richardson]

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On 05/03/2011 06:30 AM, Johnson Tran wrote:
> Hi All, 
> 
> i am trying to create a program module with two functions (conversion inches to centimeters then centimeter to inches, I have my program working although I am trying to adda Value Error function to my program but cannot seem to it to work:
> 
> 
> def Conversion():
>     print "This program converts the first value from inches to centimeters and second value centimeters to inches."
>     print "(1 inch = 2.54 centimeters)"
>     inches = input("Enter length in inches: ")
>     centimeters = 2.54 * inches
>     print "That is", centimeters, "centimeters."
> 
>     centimeters = input("Enter length in centimeters: ")
>     inch = centimeters / 2.54
>     print "That is", inch, "inches."
> 
>     except ValueError:
>         print "Invalid digit, please try again."
>         
> Conversion()
> 
> 
> 
> Any advice would be great, thanks!
> 
> JT

Well, you need a 'try' block before that except. Example:

try:
    foo = int("blargh")
except ValueError:
    pass

It looks like you're forgetting an important operation on the inches
variable, as well as centimeters later on.

Take a look at
http://docs.python.org/library/stdtypes.html#typesnumeric

For future questions, it's best to include what your program /is/ doing
that you think it shouldn't be, as well as any errors (tracebacks, copy
the whole thing!) you get.

- -- 
Corey Richardson
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