Gregory Ammar

1.1k total citations
22 papers, 668 citations indexed

About

Gregory Ammar is a scholar working on Computational Theory and Mathematics, Applied Mathematics and Signal Processing. According to data from OpenAlex, Gregory Ammar has authored 22 papers receiving a total of 668 indexed citations (citations by other indexed papers that have themselves been cited), including 20 papers in Computational Theory and Mathematics, 7 papers in Applied Mathematics and 6 papers in Signal Processing. Recurrent topics in Gregory Ammar's work include Matrix Theory and Algorithms (20 papers), Mathematical functions and polynomials (5 papers) and Digital Filter Design and Implementation (4 papers). Gregory Ammar is often cited by papers focused on Matrix Theory and Algorithms (20 papers), Mathematical functions and polynomials (5 papers) and Digital Filter Design and Implementation (4 papers). Gregory Ammar collaborates with scholars based in United States, Germany and Australia. Gregory Ammar's co-authors include William B. Gragg, Lothar Reichel, Volker Mehrmann, Clyde F. Martin, Paul Gader, Daniela Calvetti, Peter Benner, D. C. Sorensen, W.P. Dayawansa and Christian Mehl and has published in prestigious journals such as Mathematics of Computation, Applied Mathematics and Computation and Journal of Computational and Applied Mathematics.

In The Last Decade

Gregory Ammar

21 papers receiving 559 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Gregory Ammar United States 15 472 179 167 158 105 22 668
I. Koltracht United States 17 431 0.9× 147 0.8× 196 1.2× 221 1.4× 74 0.7× 50 849
Karla Rost Germany 13 548 1.2× 211 1.2× 121 0.7× 118 0.7× 77 0.7× 35 763
M. Tismenetsky Israel 10 371 0.8× 116 0.6× 153 0.9× 92 0.6× 126 1.2× 19 846
Georg Heinig Kuwait 15 700 1.5× 292 1.6× 165 1.0× 141 0.9× 83 0.8× 52 986
Sanzheng Qiao Canada 16 401 0.8× 147 0.8× 150 0.9× 83 0.5× 77 0.7× 62 824
Plamen Koev United States 15 486 1.0× 97 0.5× 275 1.6× 114 0.7× 67 0.6× 28 769
Evgenij E. Tyrtyshnikov Russia 7 401 0.8× 176 1.0× 95 0.6× 149 0.9× 35 0.3× 7 553
Vadim Olshevsky United States 19 770 1.6× 207 1.2× 247 1.5× 256 1.6× 71 0.7× 54 1.1k
Roy Mathias United States 22 803 1.7× 414 2.3× 308 1.8× 110 0.7× 108 1.0× 53 1.2k
Adam W. Bojańczyk United States 16 519 1.1× 121 0.7× 237 1.4× 48 0.3× 121 1.2× 63 862

Countries citing papers authored by Gregory Ammar

Since Specialization
Citations

This map shows the geographic impact of Gregory Ammar's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Gregory Ammar with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Gregory Ammar more than expected).

Fields of papers citing papers by Gregory Ammar

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Gregory Ammar. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Gregory Ammar. The network helps show where Gregory Ammar may publish in the future.

Co-authorship network of co-authors of Gregory Ammar

This figure shows the co-authorship network connecting the top 25 collaborators of Gregory Ammar. A scholar is included among the top collaborators of Gregory Ammar based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Gregory Ammar. Gregory Ammar is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Faybusovich, Leonid, Gregory Ammar, & William B. Gragg. (2005). Inverse problems for orthogonal matrices, Toda flows, and signal processing. 1488–1493. 1 indexed citations
2.
Ammar, Gregory, Daniela Calvetti, William B. Gragg, & Lothar Reichel. (2001). Polynomial zerofinders based on Szegő polynomials. Journal of Computational and Applied Mathematics. 127(1-2). 1–16. 10 indexed citations
3.
Ammar, Gregory, Christian Mehl, & Volker Mehrmann. (1999). Schur-like forms for matrix Lie groups, Lie algebras and Jordan algebras. Linear Algebra and its Applications. 287(1-3). 11–39. 18 indexed citations
4.
Ammar, Gregory, Daniela Calvetti, & Lothar Reichel. (1999). COMPUTATION OF GAUSS-KRONROD QUADRATURE RULES WITH NON-POSITIVE WEIGHTS. 16 indexed citations
5.
Ammar, Gregory, Daniela Calvetti, & Lothar Reichel. (1996). Continuation methods for the computation of zeros of Szegö polynomials. Linear Algebra and its Applications. 249(1-3). 125–155. 10 indexed citations
6.
Ammar, Gregory. (1996). Classical foundations of algorithms for solving positive definite Toeplitz equations. CALCOLO. 33(1-2). 99–113. 11 indexed citations
7.
Ammar, Gregory, et al.. (1995). On an inverse eigenvalue problem for unitary Hessenberg matrices. Linear Algebra and its Applications. 218. 263–271. 18 indexed citations
8.
Ammar, Gregory, Peter Benner, & Volker Mehrmann. (1993). A MULTISHIFT ALGORITHM FOR THE NUMERICAL SOLUTION OF ALGEBRAIC RICCATI EQUATIONS. ETNA - Electronic Transactions on Numerical Analysis. 1. 33–48. 29 indexed citations
9.
Ammar, Gregory, et al.. (1993). Linear Algebra and its Applications: special issue on Numerical Linear Algebra Methods in Control, Signals and Systems. Elsevier eBooks. 1 indexed citations
10.
Ammar, Gregory, William B. Gragg, & Lothar Reichel. (1993). An analogue for Szegő polynomials of the Clenshaw algorithm. Journal of Computational and Applied Mathematics. 46(1-2). 211–216. 6 indexed citations
11.
Ammar, Gregory, William B. Gragg, & Lothar Reichel. (1992). Downdating of Szego polynomials and data-fitting applications. Linear Algebra and its Applications. 172. 315–336. 18 indexed citations
12.
Ammar, Gregory, Lothar Reichel, & D. C. Sorensen. (1992). An implementation of a divide and conquer algorithm for the unitary eigen problem. ACM Transactions on Mathematical Software. 18(3). 292–307. 28 indexed citations
13.
Reichel, Lothar, Gregory Ammar, & William B. Gragg. (1991). Discrete least squares approximation by trigonometric polynomials. Mathematics of Computation. 57(195). 273–273. 57 indexed citations
14.
Ammar, Gregory & Volker Mehrmann. (1991). On Hamiltonian and symplectic Hessenberg forms. Linear Algebra and its Applications. 149. 55–72. 41 indexed citations
15.
Ammar, Gregory & Paul Gader. (1991). A Variant of the Gohberg–Semencul Formula Involving Circulant Matrices. SIAM Journal on Matrix Analysis and Applications. 12(3). 534–540. 43 indexed citations
16.
Ammar, Gregory & William B. Gragg. (1991). $O( n^2 )$ Reduction Algorithms for the Construction of a Band Matrix from Spectral Data. SIAM Journal on Matrix Analysis and Applications. 12(3). 426–431. 13 indexed citations
17.
Ammar, Gregory & William B. Gragg. (1989). Numerical experience with a superfast real Toeplitz solver. Linear Algebra and its Applications. 121. 185–206. 31 indexed citations
18.
Ammar, Gregory & William B. Gragg. (1988). Superfast Solution of Real Positive Definite Toeplitz Systems. SIAM Journal on Matrix Analysis and Applications. 9(1). 61–76. 206 indexed citations
19.
Ammar, Gregory, William B. Gragg, & Lothar Reichel. (1988). Determination Of Pisarenko Frequency Estimates As Eigenvalues Of An Orthogonal Matrix. Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE. 826. 143–143. 19 indexed citations
20.
Ammar, Gregory & Clyde F. Martin. (1986). The geometry of matrix eigenvalue methods. Acta Applicandae Mathematicae. 5(3). 239–278. 31 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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