[drraw-users] Stacking Regex and other stuff

[Christophe Kalt]

On Jan 21, Greg Davis wrote:
| Thanks for your help. About the regex stacking, i may not have been 
| clear on the question. What im trying to do is stack two template based 
| DSs on a single graph each template based DS would contain the data from 
| about 40 rrds for a total of 80 actual DSs. So lets say template DS A 
| would be 40 stacked areas in blue and green and Template DS B would be 
| another 40 stacked areas in red and yellow stacked on top of Template A. 
| When I add the second template DS it always begins the stack at 0. So 
| far I've had to Add template A and then use 40 regular DSs stacked on 
| top of template A's output. Is this the only way to do it?

Which version of drraw are you using?

With version 2.1.1, i'm able to do this by using "STACK" as
the type in the drop down list, but this doesn't let one
control what is stacked (it's based on the previous entry).

With 2.2a2, you can't really do it.

If you want a headache, read on.
you could do this:
Say your template DS A procudes a0, a1, ... a39
Set Element to "UN,0,$,IF" and Formula to "+"
This gives a new CDEF a which is a0 + a1 + ... + a39 (skipping
NaNs).

Now, if you template DS A produces b0, b1, ... b39
Set the CDEF to "b0,$,EQ,a,0,IF,$,+"

The problem is you "b0,$,EQ" compares the value of b0 with $
(which is b0 or b1 or ... b39), but you really want to compare
the variable names, not their values.  So while it may work
most of the time, there'll be cases when it doesn't.