Publications:
- Pseudospectra, Stability radii and their relationship with Backward error for Structured Nonlinear Eigenvlaue Problems, S. S. Ahmad and G. S. Nag, Accepted for Publication in Mathematical Methods in the Applied Sciences (Wiley), 2024.
- Backward error analysis of specified eigenpairs for sparse matrix polynomials, S. S. Ahmad and P. Kanhya, Numerical Linear Algebra with Applications (Wiley) 30 (2023), pp. 1-27. https://doi.org/10.1002/nla.2476
- Backward error analysis and inverse eigenvalue problems for Hankel and Symmetric-Toeplitz structures S. S. Ahmad and P. Kanhya, Applied Mathematics and Computations, 406 (2021), 126288. https://doi.org/10.1016/j.amc.2021.126288
- Perturbation analysis on matrix pencils for two specified eigenpairs of a semisimple eigenvalue with multiplicity two, S. S. Ahmad and P. Kanhya,
Electr. Trans. Num. Anal., 52:370–390, 2020.
- Structured perturbation analysis of sparse matrix pencils with s-specified eigenpairs,, S. S. Ahmad and P. Kanhya,
Linear Algebra Appl., 602:93–119, 2020.
- Perturbation analysis of matrices over a quaternion division algebra, S. S. Ahmad I . Ali, and I. Slapnicar,
Electr. Trans. Num. Anal.,Vol. 54, pp. 128–149, 2021
- Perturbation analysis for palindromic and anti-palindromic nonlinear eigenvalue problems, S. S. AhmadElectr. Trans. Num. Anal. (ETNA), Vol. 51, pp. 151–168, 2019
- Sensitivity Analysis of Nonlinear Eigenproblems, R Alam and S. S. Ahmad, SIAM J. Matrix Anal. Appl., 40, pp.672-695, 2019.
- Localization theorems
for matrices and bounds for the zeros of polynomials over a quaternion
division algebra, S. S. Ahmad and I. Ali, Filomat , Vol. 32, pp. 553-573, 2018.
- Backward errors and pseudospectra for structured nonlinear
eigenvalue problems, S. S. Ahmad and V. Mhermann, Operators and Matrices , Vol. 10, pp. 539-556,2016.
- Bounds for eigenvalues of matrix polynomials over quaternion division algebra, S. S. Ahmad and I. Ali, Advances in Applied Clifford Algebras , Vol. 26, pp. 1095-1125,2016.
- Wilkinson's problem for matrix pencils, S. S. Ahmad and R. Alam, The electronic J. Linear Algebra (ELA), Vol. 30, pp. 632-648,2015.
- Backward errors for eigenvalues and eigenvectors of Hermitian, skew-Hermitian, H-even and H-odd matrix polynomials, S. S. Ahmad and V. Mehrmann, Linear and Multilinear Algebra (LAMA), Vol. 61, pp. 1244-1266,2013.
- Perturbation analysis for complex symmetric, skew symmetric, even, and odd matrix polynomials, S. S. Ahmad and V. Mehrmann,
ElectronicTransactions on Numerical Analysis (ETNA), Vol. 38, pp. 275-302,2011.
- On Pseudospectra, Critical points and Multiple Eigenvalues of Matrix
Pencils, S.S. Ahmad, R. Alam, and R. Byers, Siam Journal of Matrix Analysis , vol. 31, no.4, pp. 1915-1933, 2010.
- On estimation of Transient Stochastic Stability of Linear Systems, S. S. Ahmad and S. Raha, Stochastic and Dynamics, vol. 10, no. 3, pp. 385-405, 2010.
- Pseudospectra, Critical points and
Multiple Eigenvalues of Matrix Polynomials, S. S. Ahmad and R. Alam, Linear Algebra and its Applications , vol. 430, pp.1171-1195, 2009.
- The Fully Implicit Stochastic-alpha Method for Stiff Stochastic Differential Equations, S. S. Ahmad, Nigam C Parida and S. Raha, Journal of Computational Physics, vol. 228, pp. 8263--8282, 2009.
Dr. Sk. Safique Ahmad
Professor
Mathematics
safique[at]iiti.ac.in