add notes on building on Mac OS X

[rrdtool.git] / doc / rrdgraph_rpn.pod

diff --git a/doc/rrdgraph_rpn.pod b/doc/rrdgraph_rpn.pod
index c24be0f..4585850 100644 (file)
--- a/doc/rrdgraph_rpn.pod
+++ b/doc/rrdgraph_rpn.pod
@@ -1,4 +1,4 @@
-=head1 NAME  
+=head1 NAME
 
 rrdgraph_rpn - About RPN Math in rrdtool graph
 
@@ -69,15 +69,12 @@ Z<>
 
 =item Comparing values
 
-B<MIN, MAX> 
+B<MIN, MAX>
 
 Pops two elements from the stack and returns the smaller or larger,
-respectively.  The two numbers shouldn't be I<infinite> or I<unknown>,
-if they are that value is pushed back onto the stack as the result.
-
-= for comment
-XXX What happens above if both a infinite and undefined value are on the 
-XXX stack? Fritz
+respectively.  Note that I<infinite> is larger than anything else.
+If one of the input numbers is I<unknown> then the result of the operation will be
+I<unknown> too.
 
 B<LIMIT>
 
@@ -143,7 +140,7 @@ average is essentially computed as shown here:
                        delay     t0
                  <--------------->
                          delay       t1
-                     <--------------->  
+                     <--------------->
                               delay      t2
                          <--------------->
 
@@ -180,9 +177,9 @@ function cannot be used in B<VDEF> instructions.
 
 B<COUNT>
 
-Pushes the number 1 if this is the first value of the data set, the 
-number 2 if it is the second, and so on. This special value allows 
-you to make calculations based on the position of the value within 
+Pushes the number 1 if this is the first value of the data set, the
+number 2 if it is the second, and so on. This special value allows
+you to make calculations based on the position of the value within
 the data set. This function cannot be used in B<VDEF> instructions.
 
 Z<>