Imported upstream version 1.3rc4.

[pkg-rrdtool.git] / doc / rrdgraph_rpn.1

diff --git a/doc/rrdgraph_rpn.1 b/doc/rrdgraph_rpn.1
index a51f542b380098ba35e9fff84b15b54da9afa2bf..91daee45d14367fb8c4eb1170c16e94ccef7cc5a 100644 (file)
--- a/doc/rrdgraph_rpn.1
+++ b/doc/rrdgraph_rpn.1
@@ -129,7 +129,7 @@
 .\" ========================================================================
 .\"
 .IX Title "RRDGRAPH_RPN 1"
-.TH RRDGRAPH_RPN 1 "2008-02-17" "1.2.27" "rrdtool"
+.TH RRDGRAPH_RPN 1 "2008-03-15" "1.3rc4" "rrdtool"
 .SH "NAME"
 rrdgraph_rpn \- About RPN Math in rrdtool graph
 .SH "SYNOPSIS"
@@ -191,6 +191,8 @@ otherwise the value popped second is pushed back. This does, indeed,
 mean that any value other than 0 is considered to be true.
 .Sp
 Example: \f(CW\*(C`A,B,C,IF\*(C'\fR should be read as \f(CW\*(C`if (A) then (B) else (C)\*(C'\fR
+.Sp
+\&\&
 .IP "Comparing values" 4
 .IX Item "Comparing values"
 \&\fB\s-1MIN\s0, \s-1MAX\s0\fR
@@ -213,12 +215,19 @@ will always return an \fIunknown\fR
 .Sp
 Example: \f(CW\*(C`CDEF:a=alpha,0,100,LIMIT\*(C'\fR will return \fIunknown\fR if
 alpha is lower than 0 or if it is higher than 100.
+.Sp
+\&\&
 .IP "Arithmetics" 4
 .IX Item "Arithmetics"
 \&\fB+, \-, *, /, %\fR
 .Sp
 Add, subtract, multiply, divide, modulo
 .Sp
+\&\fB\s-1ADDNAN\s0\fR
+.Sp
+NAN-safe addition. If one parameter is \s-1NAN/UNKNOWN\s0 it'll be treated as
+zero. If both parameters are \s-1NAN/UNKNOWN\s0, \s-1NAN/UNKNOWN\s0 will be returned.
+.Sp
 \&\fB\s-1SIN\s0, \s-1COS\s0, \s-1LOG\s0, \s-1EXP\s0, \s-1SQRT\s0\fR
 .Sp
 Sine and cosine (input in radians), log and exp (natural logarithm),
@@ -269,7 +278,7 @@ average, ignoring all \s-1UNKNOWN\s0 values in the process.
 .Sp
 Example: \f(CW\*(C`CDEF:x=a,b,c,d,4,AVG\*(C'\fR
 .Sp
-\&\fB\s-1TREND\s0\fR
+\&\fB\s-1TREND\s0, \s-1TRENDNAN\s0\fR
 .Sp
 Create a \*(L"sliding window\*(R" average of another data series.
 .Sp
@@ -295,6 +304,11 @@ average is essentially computed as shown here:
 \&     Value at sample (t1) will be the average between (t1\-delay) and (t1)
 \&     Value at sample (t2) will be the average between (t2\-delay) and (t2)
 .Ve
+.Sp
+\&\s-1TRENDNAN\s0 is \- in contrast to \s-1TREND\s0 \- NAN\-safe. If you use \s-1TREND\s0 and one 
+source value is \s-1NAN\s0 the complete sliding window is affected. The \s-1TRENDNAN\s0 
+operation ignores all NAN-values in a sliding window and computes the 
+average of the remaining values.
 .IP "Special values" 4
 .IX Item "Special values"
 \&\fB\s-1UNKN\s0\fR
@@ -352,6 +366,8 @@ in the examples section below on how to use this.
 .Sp
 Duplicate the top element, remove the top element, exchange the two
 top elements.
+.Sp
+\&\&
 .SH "VARIABLES"
 .IX Header "VARIABLES"
 These operators work only on \fB\s-1VDEF\s0\fR statements. Note that currently \s-1ONLY\s0 these work for \fB\s-1VDEF\s0\fR.
@@ -361,6 +377,11 @@ Return the corresponding value, \s-1MAXIMUM\s0 and \s-1MINIMUM\s0 also return
 the first occurrence of that value in the time component.
 .Sp
 Example: \f(CW\*(C`VDEF:avg=mydata,AVERAGE\*(C'\fR
+.IP "\s-1STDEV\s0" 4
+.IX Item "STDEV"
+Returns the standard deviation of the values.
+.Sp
+Example: \f(CW\*(C`VDEF:stdev=mydata,STDEV\*(C'\fR
 .IP "\s-1LAST\s0, \s-1FIRST\s0" 4
 .IX Item "LAST, FIRST"
 Return the last/first value including its time.  The time for