[rrd-users] rpn to convert NaN to 0

[R Dicaire]

Hi folks, I have a CDEF that derives its value from two different
rrds, adds them, then displays the result. Sometimes one of the
sources doesn't update one of the rrds (on purpose, as this particular
thing being monitored isn't always running) so that rrd stores NaN.
However since num+NaN doesn't return num, the graph wont display CDEF
contents.

CDEF:ices=icecast,vicecast,+

Sometimes the vicecast rrd is NaN, so I'd like to 'if vicecast=NaN
then set vicecast=0'.
Would I need two CDEFs, one to convert NaN to 0, then another to add them?
What rpn statement would I need to convert NaN to 0?

Thanks

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