A Higher Order Iterative Method for Computing the Drazin Inverse

Algorithm 1

n  = 5000; number = 10; SeedRandom [123]

Table[A[j]  = SparseArray[{Band[{−100, 1100}]  -> RandomReal[20],

     Band[{1, 1}]  -> 2., Band[{1000, −50}, {n −  20, n −  25}]  -> {2.8, RandomReal[]  + I},

     Band[{600, 150}, {n −  100, n −  400]  -> {-RandomReal[3], 3. + 3 I}}, {n, n},

          0.], {j, number}];