.TH db.univar 1grass "" "GRASS 7.8.5" "GRASS GIS User's Manual"
.SH NAME
\fI\fBdb.univar\fR\fR  \- Calculates univariate statistics on selected table column.
.SH KEYWORDS
database, statistics, attribute table
.SH SYNOPSIS
\fBdb.univar\fR
.br
\fBdb.univar \-\-help\fR
.br
\fBdb.univar\fR [\-\fBeg\fR] \fBtable\fR=\fIname\fR \fBcolumn\fR=\fIname\fR  [\fBdatabase\fR=\fIname\fR]   [\fBdriver\fR=\fIname\fR]   [\fBwhere\fR=\fIsql_query\fR]   [\fBpercentile\fR=\fIfloat\fR[,\fIfloat\fR,...]]   [\-\-\fBhelp\fR]  [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR]  [\-\-\fBui\fR]
.SS Flags:
.IP "\fB\-e\fR" 4m
.br
Extended statistics (quartiles and 90th percentile)
.IP "\fB\-g\fR" 4m
.br
Print stats in shell script style
.IP "\fB\-\-help\fR" 4m
.br
Print usage summary
.IP "\fB\-\-verbose\fR" 4m
.br
Verbose module output
.IP "\fB\-\-quiet\fR" 4m
.br
Quiet module output
.IP "\fB\-\-ui\fR" 4m
.br
Force launching GUI dialog
.SS Parameters:
.IP "\fBtable\fR=\fIname\fR \fB[required]\fR" 4m
.br
Name of attribute table
.IP "\fBcolumn\fR=\fIname\fR \fB[required]\fR" 4m
.br
Name of attribute column on which to calculate statistics (must be numeric)
.IP "\fBdatabase\fR=\fIname\fR" 4m
.br
Name of database
.IP "\fBdriver\fR=\fIname\fR" 4m
.br
Name of database driver
.br
Options: \fIdbf, odbc, ogr, sqlite, pg\fR
.IP "\fBwhere\fR=\fIsql_query\fR" 4m
.br
WHERE conditions of SQL statement without \(cqwhere\(cq keyword
.br
Example: income < 1000 and population >= 10000
.IP "\fBpercentile\fR=\fIfloat[,\fIfloat\fR,...]\fR" 4m
.br
Percentile to calculate (requires extended statistics flag)
.br
Options: \fI0\-100\fR
.br
Default: \fI90\fR
.SH DESCRIPTION
\fIdb.univar\fR 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 \fIdb.select\fR to create list values for statistical calculations.
\fINOTES\fR
If the database and driver are not specified, the default values set in
\fIdb.connect\fR will be used.
.SH EXAMPLE
In this example, random points are sampled from the elevation map
(North Carolina sample dataset) and univariate statistics performed:
.br
.nf
\fC
g.region raster=elevation \-p
v.random output=samples n=100
v.db.addtable samples column=\(dqheights double precision\(dq
v.what.rast samples raster=elevation column=heights
v.db.select samples
db.univar samples column=heights
\fR
.fi
.SH SEE ALSO
\fI
v.db.univar,
r.univar,
v.univar,
db.select,
d.vect.thematic
\fR
.SH AUTHOR
Michael Barton, Arizona State University
.PP
and authors of \fIr.univar.sh\fR
.SH SOURCE CODE
.PP
Available at: db.univar source code (history)
.PP
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.PP
© 2003\-2020
GRASS Development Team,
GRASS GIS 7.8.5 Reference Manual