[Tutor] Updating index of a list

[Alan Gauld]

On 08/10/15 23:17, Alan Gauld wrote:
> On 08/10/15 20:40, Andrea Nguy wrote:
>
>> What’s happening is that I am trying to take a list of a list as such:
>
> [['1', ' james', ' 1', ' 90'],
>   ['2', ' alice', ' 1', ' 95'],
>   ['5', ' jorgen', ' 1', ' 99’]] (it continues) from a text file.
>
> When you say from a text file, do you mean you are reading the
> values in and converting them to the appropriate types? Or are
> you just adding them directly to the list? In which case they
> will all be strings?

Its late so I'm not reading clearly enough. They are all strings.
So I suspect before multiplying by a float your first job is to convert 
the numbers to floats(or ints) using float() (or int())

>> However, what I am trying to do take the indexes of thelist[0][1]

And I didn't notice this was [0,1] (' james') but read it
as [1,0] (2)


> just use a for loop like this:
>
> for sublist in thelist:
>      sublist[0] *= someFloat
>      sublist[3] *= someFloat
>
> Which changes the values in place.

Provided its the numbers you want and you convert
them to float/int first.

Sorry for my inattention,
-- 
Alan G
Author of the Learn to Program web site
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