[Tutor] Rearranging a list of numbers with corresponding index (RESOLVED)

[Ken G.]

On 03/13/2015 10:38 AM, Dave Angel wrote:
> On 03/13/2015 09:57 AM, Ken G. wrote:
>> I have been keeping track of numbers drawn in our local lotto drawings
>> into a list format as shown in a short example below. Using such list, I
>> am able to determine how often a number appears within the last 100 plus
>> drawings.
>>
>> The length of my lists range from 5, 15, 35, 59and 75 long. I will give
>> an example of one of my short list.
>>
>> PowerPlay = [0, 0, 61, 32, 11, 14]
>>
>> Disregarding index 0 and 1, I can see and print the following:
>>
>> Index    Number
>> 2 61
>> 3 32
>> 4     11
>> 5     14
>>
>> showing that number 2 appears 61 times, number 3 appears 32 times,
>> number 4 appears 11 times and number 5 appears 14 times within last 100
>> plus drawings.
>>
>> How I best rearrange the numbers from high to low with its corresponding
>> index number such as below:
>>
>> Number Index
>> 61                2
>> 32                3
>> 14 5
>> 11     4
>>
>> showing the number 2 appears 61 times, number 3 appears 32 times, number
>> 5 appears 14 times and number 4 appears 11 times. I know that using
>>
>> MegaBall.reverse()
>>
>> sort the number from high to low but the index numbers still remain in
>> the same positions.
>>
>> Thanks for pointing out the way to do this.
>>
>
> Make a list of tuples by doing something like:
> new_list = [ (cnt, index) for index, cnt in enumerate(power_play) ]
>
> to produce:
>   [ (0, 0), (0, 1), (61, 2), (32, 3), (11, 4), (14, 5) ]
>
> then sort it with reverse=True.  When you print it, just omit the 
> items that have zero as their count.  (they'll be at the end, anyway)
>
> Lots of other variants, some more concise.  And other approaches might 
> be cleaner if we change how we generate the list.
>
> (I tried it briefly using Python 3.4)
>
>
I will be studying this also. I am still using Python 2.7.6 as that is 
the latest as provided by Ubuntu 14.04.1. With thanks to all, I was able 
to resolve my request for assistance here in this forum. Thanks Peter.

Ken