[Tutor] Is this correct syntax for what I want?

[Alan Gauld]

> The data structure is:
> mydata = [(Checking, 12.50),(Savings, 34.50)] 
> 
> And I want the result to look like this:
> mydata = [(Checking, 19.50),(Savings, 34.50)]
> 
> So how do I do this?

OK, The problem is that you cannot change the contents of a
tuple, you can only create a new tuple. Therefore you are 
probably better changing to a list or dictionary.

>From the look of the data I'd suggest a dictionary might 
be best:

myData = { 'Checking': 12.50, 'Savings': 34.50}

Then you can do:

myData['Checking'] += 7.00

If you decide to go for a list then it would look like:

myData = [['Checking', 12.5],['Savings',34.50]]

And you would modify it with:

myData[0][1] += 7    # [0][1] = second element of first list

But I think you will agree the dictionary approach looks 
a lot nicer, so unless there is a good reason why you 
can't use that I'd strongly recommend a dictionary.

HTH,

Alan Gauld
Author of the Learn to Program web site
http://www.freenetpages.co.uk/hp/alan.gauld