[GRASS-SVN] r71208 - grass/trunk/scripts/v.db.univar

[svn_grass at osgeo.org]

Author: mlennert
Date: 2017-06-22 06:24:53 -0700 (Thu, 22 Jun 2017)
New Revision: 71208

Modified:
   grass/trunk/scripts/v.db.univar/v.db.univar.html
Log:
v.db.univar: make difference to v.univar clearer in man page

Modified: grass/trunk/scripts/v.db.univar/v.db.univar.html
===================================================================
--- grass/trunk/scripts/v.db.univar/v.db.univar.html	2017-06-22 13:24:21 UTC (rev 71207)
+++ grass/trunk/scripts/v.db.univar/v.db.univar.html	2017-06-22 13:24:53 UTC (rev 71208)
@@ -3,9 +3,18 @@
 <em>v.db.univar</em> calculates basic univariate statistics for numeric
 attributes in a vector attribute table. It will calculate minimum, 
 maximum, range, mean, standard deviation, variance, coefficient of 
-variation, quartiles, median, and 90th percentile.
-It uses <em>db.select</em> to create list values for statistical calculations.
+variation, quartiles, median, and 90th percentile. 
 
+<p><em>v.db.univar</em> uses <em>db.univar</em> and thus <em>db.select</em>
+to get the attribute values on which it calculates the statistics.
+This means that statistics are calculated based on the entries in the attribute
+table, not based on features. Each attribute value is read once per category 
+present in the attribute table, even if there are more than one feature with 
+the same category value. If a feature has more than one category value, and 
+each of these are present in the attribute table, the attribute will be read 
+once per category value. For feature-based, instead of attribute table-based,
+univariate statistics on attributes see <a href="v.univar.html">v.univar</a>.
+
 <em>NOTES</em>
 
 A database connection must be defined for the selected vector layer.