I am using snmp to poll interface stats from a device, which is only returning total packets received on interface, I am polling every 60 seconds. Is there any way in dashboard to take the difference between those values and then divide by 60t to get packets per second and display this value in dashboard? (<event1 value> - event2 value>)/60. Dashboard would need to do this for each event coming in.
The streamstats command can give you the difference of a field between events. Then use eval to do the division.
... | streamstats window=2 range(foo) as diff
| eval diff=diff/60