Rank-preserving extensions of band matrices |
| |
| Authors: | Robert L. Ellis David C. Lay |
| |
| Affiliation: | Department of Mathematics , University of Maryland , College Park, Maryland, 20742 |
| |
| Abstract: | Existence and uniqueness problems are studied for extensions of a band matrix R such that the rank of the extension does not exceed the maximum of the ranks of the submatrices in the band of R. Applications are given to positive semidefinite extensions and extensions of lower-triangular matrices to contractions or to unitary matrices. |
| |
| Keywords: | |
|
|
