I have following structure 
 $data = { 1990 => [ 1,2,3],
           1991 => [2,3,5],
           1992 => [1,2,7,9],
 ....
};

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Assume that keys are 'years' and lists are id for some items. I like to find local max, ie.. I can select years from 1990..1999 and want to find out, which are the 10 most popular items in that window for given year. I like to have the results in strip fashion for first k items. So output should look like 'year'X 'item' where each entry in table tells me if item is popular in that year or not. Further sorting to represent minimum gaps at the top would be nice too. For example: Years( 1995..1999). The last column represents the counts in given year. 
ItemID  1995    1996    1997    1998    1999
20      =       =       =       =       =               5
5               =       =       =       =               4
6       =               =       =       =               4
7       =               =       =       =               4
12      =       =       =               =               4
14      =       =       =       =                       4
4       =       =               =                       3
9       =       =                       =               3
10      =               =       =                       3
16              =       =               =               3
1               =       =                               2
2       =               =                               2
3       =                               =               2
8               =                       =               2
11                              =       =               2
13      =                       =                       2
17              =       =                               2
19              =                       =               2
15                              =                       1
18                              =                       1
This is not home work, and I have already written some code. I like to know, if there are any modules available..to achieve what I am looking for.

Thanks,

--Artist

In reply to Windows Maximums by artist

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