v.sample manual: example updated

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@62695 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.sample/v.sample.html

@@ -29,27 +29,29 @@ important.
 
 <h2>EXAMPLE</h2>
 
-Comparison of "elevation.dem" and "elevation.10m" Spearfish maps
-at random places:
+Comparison of "elev_ned_30m" and "elev_srtm_30m" North Carolina
+sample dataset elevation models at random positions:
 
 <div class="code"><pre>
-#generate random points:
+# set computational region:
+ g.region rast=elev_srtm_30m -p
+# generate random points:
  v.random output=random n=100
-#add table with one column:
- v.db.addtable random col="el10 double"
-#transfer elevations at random points into table:
- v.what.rast rast=elevation.10m vect=random col=el10
-#verify:
+# add table with one column:
+ v.db.addtable random col="elev_srtm30 double precision"
+# transfer elevations at random points into table:
+ v.what.rast map=random rast=elev_srtm_30m col=elev_srtm30
+# verify:
  v.db.select random
 
-#generate sampling from other elevation map:
- v.sample in=random col=el10 rast=elevation.dem out=elev_sample
+# perform sampling on other elevation map:
+ v.sample in=random col=elev_srtm30 rast=elev_ned_30m out=elev_samples
 
 #verify:
- v.db.select elev_sample
+ v.db.select elev_samples
 
 #univariate statistics of differences between elevation maps:
- v.univar elev_sample col=diff type=point
+ v.univar elev_samples column=diff type=point
 </pre></div>