Operating on streamed data

[parasram]

Hi,

I am sampling 2 analog channels at 20khz, looking for 1ms pulses (~ 10 pulses in a 5s window) and measuring the time between the pulses.

I have the streaming working and have the channels with 5s histories.

The plan is to run a function on the Channel's event to populate an array of timestamps.

I understand that the Channels' events are called when a block is transferred in streaming mode.

Is there a way to determine the size of the data array in a block, so that I operate only on fresh data in the channel's event?

Thanks,

Ryan

[AzeoTech]

No as that is determined by the LabJack UD. However, you can get around it by using standard DAQFactory tools, namely subsetting by time. Simply use a variable to store the time of the last data point you processed, then you can just get the new data points by doing something like:

myChan[systime(), lastTime + 0.00001]

[AzeoTech]

BTW: make sure and use functions like search() and filter() to process through array data since the Event is going to need to be fast.