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Re: Combining Two Lists

  • To: mathgroup at smc.vnet.net
  • Subject: [mg127031] Re: Combining Two Lists
  • From: nanobio9 <kuokan.liang at gmail.com>
  • Date: Tue, 26 Jun 2012 04:46:17 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • References: <js6j0e$87r$1@smc.vnet.net>

Hi,

I have no idea of how much more programming will be 'little' enough
for you. My penny is, for example for the second list (let's suppose
that it is called list2), you can group the data concerning a specific
item in a specific quarter simply by doing:

groupedList = Gather[ list2, #1[[ {1,2} ]] == #2[[ {1,2} ]] ];

Then in 'groupedList', each element (level 1) contains data pertaining
to a specific item in a specific quarter. The same should work for the
first list, too. Then it is up to you how you would like to join your
data. (property names can be compared later, too)

Best,
KKL

> Hi,
>
> I'm having a little difficulty in combining two lists.  These lists
> contain individual sets of data and then particular items within the
> set.  On one list the first column is the set the data is in and the
> second column is the particular item, and this is followed by 5
> properties of that item.  The second list starts the same, where the
> first column is the set the data is in and the second column is the
> item, but instead of having the properties listed out in individual
> columns the data set repeats itself listing the properties A,B,C,D,E,F
> all in the same column.   Below is a representative example of the two
> list.
>
> List 1
> Data Set        Item #  Property 1      Property 2      Property 3      Property 4      Property 5
> Q1                 1                6.78             25.61         30.90          48.90  0.61
> Q1                 2               12.57            23.44           5.22          37.20 6.90
> Q2                 8              18.78   21.17 11.37   2.54            0.82
> Q2                 2              34.81 14.87   15.04   36.78   4.54
> Q2                10            22.75   10.34   16.61   23.49   3.86
> Q3                 5             47.15  7.23            11.23           40.01   3.53
> Q3                8             28.71   12.41   18.40   49.17   5.99
>
> List 2
>
> Data Set        Item#   Property 6      Measure %
> Q1                1                   A      0
> Q1                1                   B      5
> Q1                1                   C     15
> Q1                1                   D     80
> Q1                1                   E      0
> Q1                1                   F      0
> Q1                2                   A     80
> Q1                2                   B     10
> Q1                2                   C     10
> Q1                2                   D      0
> Q1                2                   E      0
> Q1                2                   F      0
> Q2                2                   A      5
> Q2                2                   B      5
> Q2                2                   C      0
> Q2                2                   D      15
> Q2                2                   E      0
> Q2                2                   F      0
> Q2                8                   A      0
> Q2                8                   B      0
> Q2                8                   C      65
> Q2                8                   D      15
> Q2                8                   E      0
> Q2                8                   F      20
> Q2                10                  A      5
> Q2                10                  B      5
> Q2                10                  C      85
> Q2                10                  D      0
> Q2                10                  E      0
> Q2                10                  F      0
> Q3                5                   A      8
> Q3                5                   B      0
> Q3                5                   C      85
> Q3                5                   D      7
> Q3                5                   E      0
> Q3                5                   F      0
> Q3                8                   A      12
> Q3                8                  B               3
> Q3                8                  C               60
> Q3                8                  D               15
> Q3                8                  E               0
> Q3                8                  F               0
>
> Note that the item # are repeat between different data sets, and data
> sets are different sizes.
>
> What I would like to do is combine the two lists matching the first
> two columns, to give groups like {Q1, 1, 6.7, 25.61, 30.90, 48.90,
> 0.61,{0,5,15,80,0,0}} for each individual.  I have used Cases to
> identify matching data sets and item numbers in the two lists.  It is
> then possible to append the two portions of the list to give part of
> the desired data set.  However, this was laborious in typing in every
> data set and then item # into Cases, and impractical for large data
> sets.  I'm sure there is a way to Map Cases or Select over the list,
> and append the appropriate data when data set and item # match, but I
> haven't figured out how to do that.  Also it seems possible to use an
> if then statement; that if the data set and item # match then append,
> else move through the list.  However, I haven't figured out how to
> code for this either.  I appreciate any help.
>
> Thanks,
>
> Hershel



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