Hi Jordan,
The "Estimate Subarray 1 configuration" option on the System Design page of SAM's Detailed PV model uses code that is embedded in the user interface to calculate the value of number of modules per string and number of strings in parallel for Subarray 1 as described in the PV Sizing and Configuration topic of Help:
samrepo.nrelcloud.org/help/pv_sizing.htm
If you want that functionality in Python, you can write it yourself based on that description. The SSC inputs that determine the size of the array are:
subarray1_modules_per_string
subarray1_nstrings
inverter_count
If your design uses more than one subarray, then you'll need to assign values to subarray[n] variables, where n is the subarray number between 1 and 4, inclusive.
Best regards,
Paul.