Question about using for-loop to generate array from DAQmx. Thanks!

I have a laser system with a frequency of 1kHz, I am using this 1kHz signal to trigger the DAQmx and get the data from a photodetector, e.g. I will get 1000 data points during 1 second from DAQmx, but I need to separate this 1000 data points into the even and odd list, which is two list of 500 data points, e.g.. The 1st, 3rd, ... 99th data is one array, the 2nd, 4th,... 10th data is another array, then I will do further calculations based on these two arrays.
To seperate the even and odd data, the only way I can find is put these 1000 points into an array and then seperate them afterwards.
Can I do things like this pic?
I don't know the speed of the for loop, because the 1kHz trigger is always there, once it is triggered, the DAQmx read will give a data point, if the speed of the for-loop( the time from the end of a loop to the beginning of the next loop) is slower than the 1kHz trigger, then the for-loop will miss data point, then the ordering of the 1000 points in 1 second will be changed.
Or I need to put everything, e.g. AI Voltage, Trigger, sample clock, into the for-loop and then return a Y? Thanks! 

Clarification:
The VI you have posted will work as following:
1) The task will read 2 analog inputs (ai0, ai3).
2) The acquisition starts, oncece digital signal (trigger) is detected on PFI0
3) The sampling rate will be as specified in "rate" control - it is continuous analog input acquisition, which means that after trigger is received (point 2), the board will start to generate hardware clock with frequency you specify as "rate"
4) with each rising edge of that hardware clock, the measurement is taken, and stored into buffer of driver.
5) DAQmx read will try to read "number of samples per channel" number of samples each time is called - and if there is not enough measurement stored in buffer (step 4), then DAQmx read will wait until DAQ card will measure reaquested number of samples (or timeout occurs before requested number of samples has been acquired)
6) DAQmx read will be then called 1000 times - so totaly you will read 1000 * "number of samples per channel"  number of samples.
You do not have to be worried about speed of the loop. In fact, if you need to read just 1000 samples, with 1kS/s, then you can remove for loop and you can change measurement mode from continuous to finite samples, and specify number of samples to read to be 1000. You will read them all properly. I recomend you to read User Manual for your DAQ device - lets say M Series User Manual.
I hope it is clear now.
regards,
stefo

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