matrix field=25 rows=10 cols=10
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  4  0  0  0  0  0  0  0  0  0
  0  0  0  4  0  0  0  0  0  0
  0  0  4  0  0  0  0  0  0  0
  0  0  0  0  0  4  0  0  0  0
  0  0  0  0  4  0  0  0  0  0
  0  0  0  0  0  0  0  0  4  0
  0  0  0  0  0  0  0  0  0  4
  0  0  0  0  0  0  4  0  0  0
  0  0  0  0  0  0  0  4  0  0