to add it. I will then try to provide an answer in the next release
of this tutorial. No feedback equals no changes! Additions to
this document are also welcome. -- Alex van den Bogaerdt
-E<lt>alex@ergens.op.het.netE<gt>
+E<lt>alex@vandenbogaerdt.nlE<gt>
=head2 Why this tutorial?
Let's compile the complete CDEF:
DEF:ds0=router1.rrd:AVERAGE
- CDEF:ds0modified=TIME,begintime,GE,TIME,endtime,LE,*,UNKN,ds0,IF
+ CDEF:ds0modified=TIME,begintime,GT,TIME,endtime,LE,*,ds0,UNKN,IF
This will return the value of ds0 if both comparisons return true. You
could also do it the other way around:
5. push 32
6. push function "plus" and process it
the stack contains now the temperature in Fahrenheit
-
+
=head2 Changing unknown into zero
rrdtool graph demo.png --title="Demo Graph" \
DEF:var=database.rrd:traffic:AVERAGE
CDEF:prev1=PREV(var)
- CDEF:time=TIME
+ CDEF:time=var,POP,TIME
CDEF:prevtime=PREV(time)
CDEF:derivate=var,prev1,-,time,prevtime,-,/
LINE3:derivate#000077:derivate
other people on the RRDtool mailing list. Please let me know if you
find errors in it or if you have trouble understanding it. If you
think there should be an addition, mail me:
-E<lt>alex@ergens.op.het.netE<gt>
+E<lt>alex@vandenbogaerdt.nlE<gt>
Remember: B<No feedback equals no changes!>
=head1 AUTHOR
Alex van den Bogaerdt
-E<lt>alex@ergens.op.het.netE<gt>
+E<lt>alex@vandenbogaerdt.nlE<gt>