<br><br><div><span class="gmail_quote">On 7/19/07, <b class="gmail_sendername">Nokes, Sam X</b> <<a href="mailto:nokess@upmc.edu">nokess@upmc.edu</a>> wrote</span>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div><div><span><font face="Arial">Realizing <font face="Courier New">v2.2a3</font> is beta, and noting a comment by Alex: "In
RRDtool 1.2 I made a start with VDEF processing. VDEFs aren't arrays like CDEFs
are, they are single values. The work is far from finished, however certain
functions are already usable."( </font></span><span><font face="Arial"><a href="http://www.vandenbogaerdt.nl/rrdtool/total.php" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">http://www.vandenbogaerdt.nl/rrdtool/total.php
</a> ),
the questions follow:</font></span></div>
<div><span><font face="Arial">(1) Are the VDEF operators
LSLSLOPE, LSLINT, and LSLCORREL usable in drraw v2.2a3?</font></span></div>
<div><span><font face="Arial">(2) Should the vnames be
placed into a linear equation: y=LSLSLOPE*LSLCORREL+LSLINT ?</font></span></div>
<div><span><font face="Arial"> We tried to
add a <font size="2">CDEF definition substituting VDEF vnames in a vpn format
(D,F,*,H,+)</font> and </font></span></div>
<div><span><font face="Arial"> received
an error from drraw stating "<font size="2">rpn expressions without DEF or CDEF
variables are not supported"</font></font></span></div>
<div><span><font face="Arial">(3) Has anyone generated a
least squares projection with rrdtool similar to the following? If so what is
the rrd invocation?</font></span></div></div></blockquote><div><br>Sam, <br></div><br>I've never used these functions in rrdtool before, but my reading of the documentation indicates that you are close with statement 2 above.
<br>I believe you need to define the VDEF variables as you're doing, and then define a CDEF using those variables and the automatic<br>COUNT variable, i.e. CDEF:trend=D,COUNT,*,H,+ (using the variables you defined above), and then graph the CDEF.
<br><br>-David<br><br><br></div><br>