v.univar(1) - Linux man page

Name

v.univar - Calculates univariate statistics for attribute. Variance and standard deviation is calculated only for points if specified.

Keywords

vector, statistics

Synopsis

v.univar
v.univar help
v.univar [-ge] map=name [type=string[,string,...]] column=string [where=sql_query] [layer=integer] [percentile=integer] [--verbose] [--quiet]

Flags:

-g: Print the stats in shell script style
-e: Calculate extended statistics
--verbose: Verbose module output
--quiet: Quiet module output

Parameters:

map=name: Name of input vector map
type=string[,string,...]: Type
Feature type(s)
Options: point,line,boundary,centroid,area
Default: point,line,boundary,centroid,area
column=string: Column name
where=sql_query: WHERE conditions of SQL statement without 'where' keyword
Example: income = 10000
layer=integer: Layer number
A single vector map can be connected to multiple database tables. This number determines which table to use.
Default: 1
percentile=integer: Percentile to calculate (requires extended statistics flag)
Options: 0-100
Default: 90

Description

v.univar 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 type=point is defined.

Extended statistics adds median, 1st and 3rd quartiles, and 90th percentile.

Example

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

Author

Radim Blazek, ITC-irst

Last changed: $Date: 2007-02-15 15:27:17 +0100 (Thu, 15 Feb 2007) $

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