<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>GRASS GIS: v.univar</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <link rel="stylesheet" href="grassdocs.css" type="text/css"> </head> <body bgcolor="white"> <img src="grass_logo.png" alt="GRASS logo"><hr align=center size=6 noshade> <h2>NAME</h2> <em><b>v.univar</b></em> - Calculates univariate statistics for attribute. Variance and standard deviation is calculated only for points if specified. <h2>KEYWORDS</h2> vector, statistics <h2>SYNOPSIS</h2> <b>v.univar</b><br> <b>v.univar help</b><br> <b>v.univar</b> [-<b>ge</b>] <b>map</b>=<em>name</em> [<b>type</b>=<em>string</em>[,<i>string</i>,...]] <b>column</b>=<em>string</em> [<b>where</b>=<em>sql_query</em>] [<b>layer</b>=<em>integer</em>] [<b>percentile</b>=<em>integer</em>] [--<b>verbose</b>] [--<b>quiet</b>] <h3>Flags:</h3> <DL> <DT><b>-g</b></DT> <DD>Print the stats in shell script style</DD> <DT><b>-e</b></DT> <DD>Calculate extended statistics</DD> <DT><b>--verbose</b></DT> <DD>Verbose module output</DD> <DT><b>--quiet</b></DT> <DD>Quiet module output</DD> </DL> <h3>Parameters:</h3> <DL> <DT><b>map</b>=<em>name</em></DT> <DD>Name of input vector map</DD> <DT><b>type</b>=<em>string[,<i>string</i>,...]</em></DT> <DD>Type</DD> <DD>Feature type(s)</DD> <DD>Options: <em>point,line,boundary,centroid,area</em></DD> <DD>Default: <em>point,line,boundary,centroid,area</em></DD> <DT><b>column</b>=<em>string</em></DT> <DD>Column name</DD> <DT><b>where</b>=<em>sql_query</em></DT> <DD>WHERE conditions of SQL statement without 'where' keyword</DD> <DD>Example: income < 1000 and inhab >= 10000</DD> <DT><b>layer</b>=<em>integer</em></DT> <DD>Layer number</DD> <DD>A single vector map can be connected to multiple database tables. This number determines which table to use.</DD> <DD>Default: <em>1</em></DD> <DT><b>percentile</b>=<em>integer</em></DT> <DD>Percentile to calculate (requires extended statistics flag)</DD> <DD>Options: <em>0-100</em></DD> <DD>Default: <em>90</em></DD> </DL> <H2>DESCRIPTION</H2> <em>v.univar</em> calculates univariate statistics of vector map features. This includes the number of features counted, minimum and maximum values, and range. Variance and standard deviation is calculated only for points if <tt>type=point</tt> is defined. <P> Extended statistics adds median, 1st and 3rd quartiles, and 90th percentile. <H2>EXAMPLE</H2> <div class="code"><pre> g.region rast=elevation.10m -p v.random out=samples n=100 v.db.addtable samples col="heights double precision" v.what.rast samples rast=elevation.10m col=heights v.db.select samples v.univar samples col=heights type=point </pre></div> <H2>SEE ALSO</H2> <EM><A HREF="v.neighbors.html">v.neighbors</A></EM> <H2>AUTHOR</H2> Radim Blazek, ITC-irst <p><i>Last changed: $Date: 2007-02-15 15:27:17 +0100 (Thu, 15 Feb 2007) $</i> <HR> <P><a href="index.html">Main index</a> - <a href="vector.html">vector index</a> - <a href="full_index.html">Full index</a></P> <P>© 2003-2008 <a href="http://grass.osgeo.org">GRASS Development Team</a></p> </body> </html>
