Imported Upstream version 1.4.7

[pkg-rrdtool.git] / doc / rrdtutorial.html

diff --git a/doc/rrdtutorial.html b/doc/rrdtutorial.html
index 4d8dede28021eb8a9573e94627d9a7a2cb8e4e21..47497800f4adc656b88dbe985188a5cf581f238c 100644 (file)
--- a/doc/rrdtutorial.html
+++ b/doc/rrdtutorial.html
@@ -113,7 +113,7 @@ element. As we are on a circle there is neither a beginning nor an end, you can
 go on and on and on. After a while, all the available places will be used and
 the process automatically reuses old locations. This way, the dataset
 will not grow in size and therefore requires no maintenance.
-RRDtool works with with Round Robin Databases (RRDs). It stores and retrieves
+RRDtool works with Round Robin Databases (RRDs). It stores and retrieves
 data from them.</p>
 <p>
 </p>
@@ -345,13 +345,18 @@ the real maximum per line is OS dependent.</p>
  920808300: 1.6666666667e-02
  920808600: 6.6666666667e-03
  920808900: 3.3333333333e-03
- 920809200: nan</pre>
-<p>If it doesn't, something may be wrong.  Perhaps your OS will print
-&quot;NaN&quot; in a different form. &quot;NaN&quot; stands for &quot;Not A Number&quot;.  If your OS
-writes &quot;U&quot; or &quot;UNKN&quot; or something similar that's okay.  If something
-else is wrong, it will probably be due to an error you made (assuming
-that my tutorial is correct of course :-). In that case: delete the
-database and try again.</p>
+ 920809200: nan
+ 920809500: nan</pre>
+<p>Note that you might get more rows than you expect. The reason for this is
+that you ask for a time range that ends on 920809200. The number that is
+written behind 920809200: in the list above covers the time range from
+920808900 to 920809200, EXCLUDING 920809200. Hence to be on the sure side,
+you receive the entry from 920809200 to 920809500 as well since it INCLUDES
+920809200. You may also see &quot;NaN&quot; instead of &quot;nan&quot; this is OS dependent.
+&quot;NaN&quot; stands for &quot;Not A Number&quot;.  If your OS writes &quot;U&quot; or &quot;UNKN&quot; or
+something similar that's okay.  If something else is wrong, it will probably
+be due to an error you made (assuming that my tutorial is correct of course
+:-). In that case: delete the database and try again.</p>
 <p>The meaning of the above output will become clear below.</p>
 <p>
 </p>