some questions about the function "compute_smap_coeffs"

[Shuhan-Guo]

Hi, Mr Ye. I am running the code you provided me. It just fits my research. And thank you again. It helped me a lot. But I had some problems and I wish you could help me if you have time.
1．I running function “compute_smap_coeffs” successfully. But it have “NA” value the first few rows and I don‘t know the reason. If you had seen this before
2. The results I got make me confused. This picture is my result. “SP1”,“SP2”,”SP3”…. represent different species in diatom community.
And I guess:
SP1.SP1 means the intraspecific density restriction of SP1->SP2
SP1.SP2 means the interaction strength of SP1->SP2.
But I don’t know my understanding right or wrong so I want to check with you

Besides that, it was difficult for me to guess what SP1.const meant, if you could tell me about this I would be very grateful.