[rrd-users] heat map support

Simon Hobson linux at thehobsons.co.uk
Mon Aug 9 08:54:41 CEST 2010

Stefan Parvu wrote:

>Any ideas if I can produce a heat map using
>rrdtool ?

You mean what is effectively a bitmap where the colour of each pixel 
represents the value stored in a 2 dimensional array ? Well 
potentially you could do it, but only by a lot of messing around to 
massage the data into an un-natural form.

The only way I could see it working would be to have each row of 
pixels as a separate DS, and then use multiple conditional statements 
to map values to multiple CDEFs for colours or "Nan"s, do multiple 
plots to get that row of pixels in the graph - rinse and repeat for 
each row.
It would be hard work and isn't what RRDtool is designed for. I'd 
suggest you'd be better with one of the other free tools that is 
designed for that sort of thing. GNUplot ?

Simon Hobson

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