Hua-Zhou

import Base: convert, rand, size, getindex, A_mul_B!

immutable PLINK1Matrix <: AbstractMatrix{UInt8}
    m :: Int
    n :: Int
    data :: Array{UInt8}
end

size(M::PLINK1Matrix, i::Int) = i==1 ? M.m : i==2 ? M.n : error()
size(M::PLINK1Matrix) = (M.m, M.n)