Date: Apr 10, 2013 10:16 PM
Author: Peter Perkins
Subject: Re: how to find unique rows and calculate the average.

Alan, if you have access to the Statistics Toolbox, a combination of 
cell2dataset (or create the dataset array directly by reading a file)
and grpstats solves this easily. Use UniqueID as the grouping variable.

Hope this helps.


On 4/9/2013 5:32 PM, Alan Hitch wrote:
> I have a matrix (2563x19) with text and numeric characters. The first
> row is a header.
>
> e.g. [Site Marshtype Date Species Throw Season Year
> UniqueID Total Pass1 Pass2 Pass3 Pass4 Pass5
> Pass6 Pass7 Pass8 Pass9 Pass10
> 3BAB Brackish 27-Oct-04 PAPU 2 Fall 2004
> 3BAB38287PAPU 35 25 9 0 1 0 0 0 0 0 0
> 3BAB Brackish 27-Oct-04 POLA 2 Fall 2004
> 3BAB38287POLA 79 46 19 9 5 0 0 0 0 0 0
> 3BAB Brackish 27-Oct-04 GAAF 2 Fall 2004
> 3BAB38287GAAF 64 45 13 6 0 0 0 0 0 0 0
> 3BAB Brackish 27-Oct-04 CYVA 2 Fall 2004
> 3BAB38287CYVA 11 2 4 2 3 0 0 0 0 0 0
> 3BAB Brackish 27-Oct-04 LUPA 2 Fall 2004
> 3BAB38287LUPA 20 11 2 4 2 1 0 0 0 0 0]
>
> I would like to get average values (Total) of particular rows that have
> identical column values (column of interest is UniqueID) and create a
> new matrix with the calculated mean and associated UniqueID. For each
> UniqueID there are between 2 and 3 values.
>
> Like this:
>
> [3BAB38287PAPU 234
> 3BAB38287POLA 456
> 3BAB38287GAAF 35]
>
> Could someone help me with this? I have tried a lot of things and
> nothing seems to be working.
>
> Thanks
> Alan