PCA, snp matrix, human population

For human snp in maxtrix

                  site1   site2
people1      0          1...
people2      2          0 ...

0: aa, 1 Aa, 2 AA

So, PCA can be calculated from this matrix pretty straightfoward.

Ref
https://www.youtube.com/watch?v=SlnOxHhypDg