This paper uses unit lower triangular matrices to solve the nonnegative inverse eigenvalue problem for various sets of real numbers. This problem has remained unsolved for many years for $n \geq 5.$ The inverse of the unit lower triangular matrices can be easily calculated and the matrix similarities are also helpful to be able to solve this important problem to a considerable extent. It is assumed that in the given set of eigenvalues, the number of positive eigenvalues is less than or equal to the number of nonpositive eigenvalues to find a nonnegative matrix such that the given set is its spectrum.
Nazari, A., & Nezami, A. (2024). Inverse eigenvalue problem of nonnegative matrices via unit lower triangular matrices (Part I). Journal of Mathematical Modeling, 12(1), 117-130. doi: 10.22124/jmm.2023.21759.2092
MLA
Alimohammad Nazari; Atiyeh Nezami. "Inverse eigenvalue problem of nonnegative matrices via unit lower triangular matrices (Part I)". Journal of Mathematical Modeling, 12, 1, 2024, 117-130. doi: 10.22124/jmm.2023.21759.2092
HARVARD
Nazari, A., Nezami, A. (2024). 'Inverse eigenvalue problem of nonnegative matrices via unit lower triangular matrices (Part I)', Journal of Mathematical Modeling, 12(1), pp. 117-130. doi: 10.22124/jmm.2023.21759.2092
VANCOUVER
Nazari, A., Nezami, A. Inverse eigenvalue problem of nonnegative matrices via unit lower triangular matrices (Part I). Journal of Mathematical Modeling, 2024; 12(1): 117-130. doi: 10.22124/jmm.2023.21759.2092
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