NAME

       v.db.univar   -  Calculates  univariate  statistics  on  selected table column for a GRASS
       vector map.

KEYWORDS

       vector, statistics

SYNOPSIS

       v.db.univar
       v.db.univar help
       v.db.univar   [-e]   table=string   column=string    [database=string]     [driver=string]
       [where=string]   [--verbose]  [--quiet]

   Flags:
       -e
           Extended statistics (quartiles and 90th percentile)

       --verbose
           Verbose module output

       --quiet
           Quiet module output

   Parameters:
       table=string
           Name of data table

       column=string
           Column on which to calculate statistics (must be numeric)

       database=string
           Database/directory for table

       driver=string
           Database driver

       where=string
           WHERE conditions of SQL statement without 'where' keyword

DESCRIPTION

       v.db.univar calculates basic univariate statistics for numeric attributes in a data table.
       It will calculate minimum, maximum, range, mean, standard deviation, variance, coefficient
       of  variation,  quartiles,  median, and 90th percentile.  It uses db.select to create list
       values for statistical calculations.  NOTES If the database and driver are not  specified,
       the default values set in db.connect will be used.

EXAMPLE

       In  this  example, random points are sampled from the elevation map (North Carolina sample
       dataset) and univariate statistics performed:
       g.region rast=elevation -p
       v.random output=samples n=100
       v.db.addtable samples column="heights double precision"
       v.what.rast samples raster=elevation colum=heights
       v.db.select samples
       v.db.univar samples colum=heights

SEE ALSO

        r.univar, v.univar,, db.select, d.vect.thematic

AUTHOR

       Michael Barton, Arizona State University

       and authors of r.univar.sh

       Last changed: $Date: 2011-09-04 06:23:30 -0700 (Sun, 04 Sep 2011) $

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       © 2003-2013 GRASS Development Team