Measuring increase of voltage between specific time or duration

[n@ndy]

Hi,

     I am working on a VI to acquire voltage signal from DAQ and converting it to graph as a part of it.. While analysing graph, i want to measure the increase of voltage for a specific time i.e. to measure voltage increased for every second(from 1 sec to 2sec how much voltage have increased)..which function can be used?  pls help me...  

[p-rose]

Wouldn't that just be the derivative? Are you working with waveform data type?