compariing data between loop iterations

[Reserved]

I am acquiring temperature data with an NI 9213 Thermocouple Reader and DAQ Assistant within a While loop.  I need to compare the temperature from one channel in a loop iteration with the temperture from the same channel in the previous iteration.  The data collected in each iteration is delivered to both a Chart and a data storage file.  I know how to obtain the temperature from the data array in the present iteration, but don't know how to obtain the temperature from the previous iteration, except perhaps by reading the whole file into an array, determining the size of the array, and interrogating the last entries. That seems a bit silly for every loop iteration, and perhaps even embarrassing.   Any suggestions?

[johnsold · Accepted solution]

Put the data into a shift register. The left terminal of the shift register will have the data from the previous iteration.

Lynn

[Reserved]

Thanks for your rapid reply and solution, Lynn. 

[Ranjeet_Singh]

Hi Reserved,

                               Shift register is best way for that. Here

[Reserved]

Thanks to you also, Ranjeet.  I am hoping that, after a few more decades of learning to program in Labview, my questions will become more sophisticated.  Cheers.