Hello everyone,

I have a 4x3 matrix called myMatrix. The elements are either lists, e.g., {-5} or {-5,4}, or the result of subtraction that failed because the first number was missing from the association from which it was obtained, e.g., Missing["KeyAbsent", "2,838,683"] - 13.

 myMatrix = ({
      {{-5}, Missing["KeyAbsent", "2,838,683"] - 13, 
       Missing["KeyAbsent", "2,028,297"] - 13},
      {{-5, 4}, Missing["KeyAbsent", "2,838,683"] - 13, 
       Missing["KeyAbsent", "2,028,297"] - 13},
      {{-5}, Missing["KeyAbsent", "2,838,683"] - 13, 
       Missing["KeyAbsent", "2,028,297"] - 13},
      {Missing["KeyAbsent", "2,841,787"] - 18, {-5}, {2}}
     })

I want to delete the elements (or replace them) containing Missing but can't figure out how to do it.

DeleteCases[myMatrix, _Missing - 13, {2}]

works for those elements where 13 was to be subtracted; likewise for 18. Then why doesn't

DeleteCases[myMatrix, _Missing - _Integer, {2}]

work for any element?

Any tip would be much appreciated.

Greg