Subtracting row minima

General Usage Performance
8

If you want it be super fast, write a single nested-loop for both operations like this:

function subMins!(mat)
    mcols = minimum(mat, dims=1)
    mrows = minimum(mat, dims=2)
    for j = 1:size(mat,2), i = 1:size(mat,1)
        mat[i,j] -= mrows[i] + mcols[j] 
    end  
end 

using BenchmarkTools
mat = rand(UInt16, 16000, 16000)
@btime subMins!($mat)
  290.291 ms (32 allocations: 63.41 KiB)