NAME

       db.univar  - Calculates univariate statistics on selected table column.

KEYWORDS

       database, statistics, attribute table

SYNOPSIS

       db.univar
       db.univar --help
       db.univar     [-eg]     table=name     column=name      [database=name]      [driver=name]
       [where=sql_query]    [percentile=float[,float,...]]    [--help]   [--verbose]    [--quiet]
       [--ui]

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

       -g
           Print stats in shell script style

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       table=name [required]
           Name of attribute table

       column=name [required]
           Name of attribute column on which to calculate statistics (must be numeric)

       database=name
           Name of database

       driver=name
           Name of database driver
           Options: dbf, odbc, ogr, sqlite, pg

       where=sql_query
           WHERE conditions of SQL statement without ’where’ keyword
           Example: income < 1000 and inhab >= 10000

       percentile=float[,float,...]
           Percentile to calculate (requires extended statistics flag)
           Options: 0-100
           Default: 90

DESCRIPTION

       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 raster=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
       db.univar samples colum=heights

SEE ALSO

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

AUTHOR

       Michael Barton, Arizona State University

       and authors of r.univar.sh

       Last changed: $Date: 2014-12-19 22:55:37 +0100 (Fri, 19 Dec 2014) $

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