All commands to be run in the terminal.
See Plink documentation here.
For each of the six poulations, use Plink to calculate LD between each pair of loci. The "--r2 square" flag to Plink will produce a LxL matrix of pairwise r2, with L as the number of loci.
plink --bfile ./work/Koppen_ODD --r2 square --out ./work/Koppen_ODD
plink --bfile ./work/Koppen_EVEN --r2 square --out ./work/Koppen_EVEN
plink --bfile ./work/Nome_ODD --r2 square --out ./work/Nome_ODD
plink --bfile ./work/Nome_EVEN --r2 square --out ./work/Nome_EVEN
plink --bfile ./work/Puget_ODD --r2 square --out ./work/Puget_ODD
plink --bfile ./work/Puget_EVEN --r2 square --out ./work/Puget_EVEN