@article{GutheilBergGrotendorst2012, author = {Gutheil, Inge and Berg, Tommy and Grotendorst, Johannes}, title = {Performance Analysis of Parallel Eigensolvers of two Libraries on BlueGene/P}, series = {Journal of Mathematics and Systems Science}, volume = {2}, journal = {Journal of Mathematics and Systems Science}, number = {4}, publisher = {David Publishing}, address = {Libertyville}, issn = {2159-5291}, doi = {10.17265/2159-5291/2012.04.003}, pages = {231 -- 236}, year = {2012}, abstract = {Many applications in computational science and engineering require the computation of eigenvalues and vectors of dense symmetric or Hermitian matrices. For example, in DFT (density functional theory) calculations on modern supercomputers 10\% to 30\% of the eigenvalues and eigenvectors of huge dense matrices have to be calculated. Therefore, performance and parallel scaling of the used eigensolvers is of upmost interest. In this article different routines of the linear algebra packages ScaLAPACK and Elemental for parallel solution of the symmetric eigenvalue problem are compared concerning their performance on the BlueGene/P supercomputer. Parameters for performance optimization are adjusted for the different data distribution methods used in the two libraries. It is found that for all test cases the new library Elemental which uses a two-dimensional element by element distribution of the matrices to the processors shows better performance than the old ScaLAPACK library which uses a block-cyclic distribution.}, language = {en} } @article{Grotendorst2012, author = {Grotendorst, Johannes}, title = {Supercomputer programmieren - ein besonderes Studienangebot in J{\"u}lich}, series = {Junge Wissenschaft. 27 (2012), H. 94}, journal = {Junge Wissenschaft. 27 (2012), H. 94}, publisher = {-}, isbn = {0179-8529}, pages = {12 -- 14}, year = {2012}, language = {de} } @article{Grotendorst2012, author = {Grotendorst, Johannes}, title = {IAS Winter School: Hierarchical Methods for Dynamics in Complex Molecular Systems}, series = {Innovatives Supercomputing in Deutschland : inSiDE. 10 (2012), H. 1}, journal = {Innovatives Supercomputing in Deutschland : inSiDE. 10 (2012), H. 1}, publisher = {-}, pages = {104}, year = {2012}, language = {en} } @book{Grotendorst2012, author = {Grotendorst, Johannes}, title = {Hierarchical methods for dynamics in complex molecular systems : IAS Winter School, 5 - 9 March 2012, Forschungszentrum J{\"u}lich GmbH ; lecture notes / ed. by Johannes Grotendorst, Godehard Sutmann, Gerhard Gompper, Dominik Marx}, publisher = {Forschungszentrum J{\"u}lich}, address = {J{\"u}lich}, isbn = {978-3-89336-768-9}, pages = {VI, 540 S. zahlr. Ill. u. graph. Darst.}, year = {2012}, language = {en} } @article{Grotendorst1991, author = {Grotendorst, Johannes}, title = {Maple programs for converting series expansions to rational functions using the Levin transformation automatic generation of FORTRAN functions for numerical applications}, series = {Computer Physics Communications. 55 (1991), H. 3}, journal = {Computer Physics Communications. 55 (1991), H. 3}, isbn = {0010-4655}, pages = {325 -- 335}, year = {1991}, language = {en} } @article{Grotendorst1992, author = {Grotendorst, Johannes}, title = {Algorithms of mixed symbolic-numeric type for rational approximation}, series = {Artificial intelligence, expert systems and symbolic computing : selected and revised papers from the IMACS 13th World Congress [on Computation and Applied Mathematics], Dublin, Ireland, July 1991 / ed. by Elias N. Houstis ...}, journal = {Artificial intelligence, expert systems and symbolic computing : selected and revised papers from the IMACS 13th World Congress [on Computation and Applied Mathematics], Dublin, Ireland, July 1991 / ed. by Elias N. Houstis ...}, publisher = {North-Holland}, address = {Amsterdam}, isbn = {0-444-89703-8}, pages = {145 -- 154}, year = {1992}, language = {en} } @article{Grotendorst1991, author = {Grotendorst, Johannes}, title = {A Maple package for transforming series, sequences and functions}, series = {Computer Physics Communications. 67 (1991), H. 2}, journal = {Computer Physics Communications. 67 (1991), H. 2}, isbn = {0010-4655}, pages = {325 -- 342}, year = {1991}, language = {en} } @article{Grotendorst1990, author = {Grotendorst, Johannes}, title = {Approximating functions by means of symbolic computation and a general extrapolation method}, series = {Computer Physics Communications. 59 (1990), H. 2}, journal = {Computer Physics Communications. 59 (1990), H. 2}, isbn = {0010-4655}, pages = {289 -- 301}, year = {1990}, language = {en} } @book{GrotendorstDornseifferSchoberth1994, author = {Grotendorst, Johannes and Dornseiffer, J{\"u}rgen and Schoberth, Siegfried M.}, title = {Symbolic-numeric computation techniques for problem-solving in Physical Chemistry and Biochemistry . Stand 08.06.1994 / Grotendorst, Johannes ; Dornseiffer, J{\"u}rgen ; Schoberth, Siegfried M.}, publisher = {ZAM, KFA}, address = {J{\"u}lich}, pages = {9 S.}, year = {1994}, language = {en} } @book{GrotendorstDornseifferSchoberth1994, author = {Grotendorst, Johannes and Dornseiffer, J{\"u}rgen and Schoberth, Siegfried M.}, title = {Symbolic-numeric computation techniques for problem-solving in Physical Chemistry and Biochemistry . Stand 08.06.1994 / Grotendorst, Johannes ; Dornseiffer, J{\"u}rgen ; Schoberth, Siegfried M.}, publisher = {ZAM, KFA}, address = {J{\"u}lich}, pages = {9 S.}, year = {1994}, language = {en} }