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I am currently working on problems involving matrix decompositions, matrix compressions, numerical ranges, and numerical radii.

Graduate students

• Current
  • Alexander Niño Gabriel C. Magtangob: M.S. Mathematics
  • Eloise P. Misa: Ph.D. Mathematics
  • Jomar Kevin D. Sta. Ana: Ph.D. Mathematics (co-advised with Ralph L. de la Cruz)
• Former
  • Clark Kenneth Espinosa: M.S. Mathematics (2024)
    Thesis title: On the Polar Decomposition of Generalized Companion Matrices
  • Juan Paolo C. Santos: M.S. Mathematics (2024)
    Thesis title: On commutators of unipotent matrices of index 2

Undergraduate students

• Current
  • Endaniel Aldrix J. Felix: B.S. Mathematics
  • Carl Justine C. Lao: B.S. Mathematics
• Former
  • Japheth G. Dela Torre: B.S. Mathematics (2024)
    Thesis title: A Family of Completely PPT Maps
  • John Victor T. Noynoyan: B.S. Mathematics (2024)
    Thesis title: On Elliptical Numerical Ranges
  • Aedan Jarrod A. Potot: B.S. Mathematics (2024)
    Thesis title: Schur-Horn theorem and Ky Fan principle for symplectic eigenvalues
  • Alfonso M. Gavino: B.S. Mathematics (2023)
    Thesis title: Relating the Geometric Multiplicities of a Matrix with its Submatrices
  • Alexander Niño Gabriel C. Magtangob: B.S. Mathematics (2023)
    Thesis title: Schur’s Triangularization Theorem and Sylvester’s Theorem for Dual Complex Matrices
  • Samantha Ysabel D. Alcantara: B.S. Mathematics (2023)
    Thesis title: On the numerical range of {1,2}-inverses of a matrix
  • Ricci Mae DC. Margallo: B.S. Mathematics (2022)
    Thesis title: Ritz Values of Weighted Shift Matrices

First Semester AY 2024-2025

• Classes
  • Math 21 TWHFQ-8, TWThF 7:15-8:15
  • Math 21 TWHFR-8, TWThF 8:45-9:45
  • Math 21 TWHFU-2, TWThF 10:15-11:15
  • Math 21 TWHFV-7, TWThF 11:45-12:45
• Consultation Hours
  • TWThF 1:00-3:30

1. K. L. Dela Rosa and H. J. Woerdeman, Completing an Operator Matrix and the Free Joint Numerical Radius, Complex Anal. Oper. Theory 16, 114 (2022).
2. K. L. Dela Rosa and H. J. Woerdeman, Continuity of submatrices and Ritz sets associated to a point in the numerical range, Linear Algebra Appl. 624 (2021) 1-13.
3. K. L. Dela Rosa and H. J. Woerdeman, Location of Ritz values in the numerical range of normal matrices, Linear Multilinear Algebra (2020).
4. K. L. Dela Rosa, D. I. Merino, A. T. Paras, The subspaces spanned by Householder vectors associated with an orthogonal or a symplectic matrix, Linear Algebra Appl. 546 (2018) 37-49.
5. R. L. de la Cruz, K. L. Dela Rosa, Each $2n$-by-$2n$ complex symplectic matrix is a product of $n+1$ commutators of $J$-symmetries, Linear Algebra Appl. 517 (2017) 53-62.
6. R. L. de la Cruz, K. L. Dela Rosa, D. I. Merino, A. T. Paras, The Cartan-Dieudonné-Scherk theorems for complex $S$-orthogonal matrices, Linear Algebra Appl. 458 (2014) 251-260.
7. K. L. Dela Rosa, D. I. Merino, A. T. Paras, The $J$-Householder matrices, Linear Algebra Appl. 436 (2012) 1189-1194.