July 2017 1HaskellADay 1Liner

• July 7th, 2017:
  In LU-decomposition of matrices you have square P-matrix:
  [[1,0..],
   [0,2,0..],
   [0,0,3,0..],
  ...]
  For matrices of n² size
  Code that
  
  • ∃! David Turner @DaveCTurner
  • matrix n = let td = take n . drop 1 in td [td $ replicate i 0 ++ [i] ++ repeat 0 | i <- [0..]]