[rrd-users] ask about data source type

[Jaya]

hello all,
is there a way for creating/generating data source type that have is a difference between two value at different time (similar type as counter, but it wasn't divided by the time).

i.e:

time | data
0      100
5      200
10     500

then the data source would create
time | data
0      NaN
5      100
10     300


rgrds//j