[rrd-users] AREA starting at value rather than at y=0

[Joseph Mack NA3T]

using rrdtool-1.0.45

I have a value with a +/- error margin . I'd like to have an 
AREA starting at (value-error) of height 2*error to give a 
band of color corresponding to the error limits.

I've tried starting the bottom with AREA:(value-error) using 
black or white as the color of AREA, but these colors are 
obtrusive. I'd rather have a transparent AREA. (I then STACK 
2*error.) Alternately I use LINE2 for the lower limit, the 
most likely value, and the upper limit, but then there are 3 
lines and the viewer thinks I'm plotting 3 values.

Any suggestions?

Thanks Joe

-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
generator at http://www.wm7d.net/azproj.shtml
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