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How does everyone handle sweep data from loops

There's a type of test I've done a few times over the years and I'm researching what are some standard ways to handle the data in TestStand. The test type is sweeping multiple parameters in a nested loop. For example, sweep Vcc from 5.1V to 5.5V in .1V steps, at each voltage sweep Q DC Bias from 1.9 to 2.3 in steps of .2, and at each Q DC Bias sweep LO Drive Level from -5 to -20 dBm in steps of .5 dBm. For each input combination record IM3 Suppression. This example produces 310 data records.

If I did all this inside a single code module I could pass it back to TestStand as four arrays, one for each input param and one for the data. Done. I'd still need to log it.

What if I want to do the looping in TestStand? Here's how I could collect data.
1. Record the three params and one data into the ResultList as single points with Numeric Limit steps and sort it out in some datalogger callback.
2. Collect four arrays or a 2D array in Locals and then copy the arrays into the ResultList as four arrays (or 1 2D), not as scalars in #1 above. Log it in some datalogger callback.
3. Collect four arrays or a 2D array in Locals and just use a code module in the client sequence to save the data.
4. Any others?

Thanks
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Hi dowNow,

I can't immediately think of any significantly different alternatives to accomplish what you are wanting to do.  In the past, I have personally used the external code module to do the looping and measurements and then returned the data as a 2-D array.  You can then add this array to the ResultList.  This has typically given me the most efficient tests and the simplest overall setup.

Additionally, I am not sure if you are planning to store the results in a Database, but if you are, you will need to keep in mind that logging a 2-D array to a Database works differently than a 1-D array.  I have included a link to one of our KnowledgeBase articles that details exactly how to store a 2-D array in a Database:  http://digital.ni.com/public.nsf/allkb/1307679F845B162286257160000510ED
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