[GRASS-user] Extracting an area with maximum value

[Corey Moffet]

Dear GRASS users,

I have a vector layer with area features that have 1 or more categories 
and associated attributes linked with the centroid.  I would like to 
extract a single category for each centroid on the basis of some 
attribute.

For example, there are several areas in my study area and each area has 
a fire history. The area may have been burned in one or more years.  In 
one area, lets say it burned in 1950 and 1970 so the centroid for this 
area has 2 categories linked with it and the attribute YearBurn is 1950 
and 1970 for the 2 categories, respectively.  I want a new layer that 
has only one category linked to the centroid and the value 1970 (e.g., 
max(YearBurn) as LastBurn) for the attribute "LastBurn."

The database table is in dbf format.  How can this be accomplished 
without having to edit it by hand?

-- 
With best wishes and kind regards I am

Sincerely,

Corey A. Moffet
Rangeland Scientist

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