[Tutor] Just started Python

[Johnson Tran]

Ahh, I was wondering about why it didn't show the error message on the first variable. Makes sense, thanks again.

Sent from my iPhone

On Apr 27, 2011, at 5:05 PM, Alan Gauld <alan.gauld at btinternet.com> wrote:

> 
> "Johnson Tran" <aznjonn at me.com> wrote 
>> Okay so my final program is:
> 
> It works but you can improve it slightly with a simple change.
> 
>> model=raw_input("What kind of car do you drive?")
>> gallons=raw_input("How many gallons have you driven?")
>> miles=raw_input("How many miles have you driven?")
>> try:
>>   number1 = float(gallons)
>>   number2 = float(miles)
> 
> Combine these two groups of lines so that you detect the errors as soon as possible.:
> 
> try:
>  model=raw_input("What kind of car do you drive?")
>  gallons=raw_input("How many gallons have you driven?")
>  number1 = float(gallons)
>  miles=raw_input("How many miles have you driven?")
>  number2 = float(miles)
> 
> Now the user gets prompted as soon as they enter a wrong number, they don't need to guess which one was wrong...
> 
> except ValueError:
>   print "That value is the wrong type, please use a number."
> 
> And so we can make the message more specific too.
> 
>> else:
>>   print "Your average number of miles to gallons is",
>>   print number1 / number2
> 
> HTH,
> 
> -- 
> Alan Gauld
> Author of the Learn to Program web site
> http://www.alan-g.me.uk/
> 
> 
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