Recognition of hidden positive row diagonally dominant matrices
نویسندگان
چکیده
A hidden positive row diagonally dominant (hprdd) matrix is a square matrix A for which there exist square matrices C and B so that AC = B and each diagonal entry of B and C is greater than the sum of the absolute values of the off-diagonal entries in its row. A linear program with 5n2 − 4n variables and 2n2 constraints is defined that takes as input an n × n matrix A and produces C and B satisfying the above conditions if and only if they exist. A 4×4 symmetric positive definite matrix that is not an hprdd matrix is presented.
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