The syntax of pvmismatch. How do I change specific cells?

Question

I followed some advice from a thread on PVlib for Python and started using the pvmismatch package/library. I'm following the tutorial found here. What I can't seem to find out is what this line does exactly:

>>> pvsys.setSuns({0: {0: [(0.2, ) * 8, (11, 12, 35, 36, 59, 60, 83, 84)]}})

The documentation points out that this changes the shading of the last row of cells within the 1st module of the first string; but I don't quite see where the numbers correspond to the index of cells, which to the number of rows, etc. Any help on this would be appreciated!

One approach I've been trying is to just embellish the code by making changes which "make sense," for example the below:

pvsys4.setSuns({0: {0: [(0.2, ) * 8, (11, 12, 35, 36, 59, 60, 83, 84)]}, 1: {0:[(0.2,)*8, (9,9,9,9,9,9,9,9)]}})

...but that just doesn't seem like a wise or efficient way of learning about how to do this. Any ideas about how to progress would be much appreciated!

Answer 1

Thanks for using PVMismatch. Given this command from the tutorial:

>>> from pvmismatch import *
>>> pvsys = pvsystem.PVsystem()  # default 10x10 system
>>> pvsys.setSuns({0: {0: [(0.2, ) * 8, (11, 12, 35, 36, 59, 60, 83, 84)]}})

It sets the irradiance of the 1st module (0th index) in the 1st string (0th index) to 200[W/m^2] for cell indices: [11, 12, 35, 36, 59, 60, 83, 84]

Reading the dictionary from the outside in, it goes: {sting idx: {module idx: [irrad, cell idx]}}. For a standard Si module with 96 cells (like SunPower SPR-E20-327) the cells indices start at zero in the upper right corner of the module in portrait, and the proceed down & up in a serpentine pattern.

Does this image help visualize the pattern?

It shows four modules in portrait, the first two modules of the first two strings, with the bottom row of module-0 in string-0 shaded gray. The cell indices are numbered inside each module starting in the upper left corner, and the substrings are outlined with a thick border in shades of blue.