[rrd-developers] PATCH: Fix looping in rrdgraph

[Peter Stamfest]

Find attached a small patch that fixes a problem when using --rigid with 
the graph command.

The problem this patch fixes is reproducible using the following command:

rrdtool  graph a.png --rigid --start 1287948770 --end 1289406370 
--upper-limit 100 --lower-limit -100 DEF:out=/tmp/a.rrd:out:AVERAGE 
CDEF:negout=out,-1,*   AREA:negout#0000ff:out

Unfortunately, I do not have a simple way to create a RRD file exhibiting 
the problem easily, so I have to use a real-life RRD file. The gzipped 
rrddump output has a size of over 300kB, unfortunately, so I am not 
attaching this file here.

The fix also fixes some incorrect graphing of data - the graphics output 
with and without the patch is often different - with the patchless version 
being wrong... That said, I'm not 100% sure that this is the correct fix 
for the problem. It definitly improves the situation, though.

peter

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.oetiker.ch/pipermail/rrd-developers/attachments/20101109/4b7ee881/attachment.htm 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fix-large-y-values-make-rrdtool-loop.patch
Type: application/octet-stream
Size: 1250 bytes
Desc: not available
Url : http://lists.oetiker.ch/pipermail/rrd-developers/attachments/20101109/4b7ee881/attachment.obj