TY  - JOUR
A1  - Grotendorst, Johannes
T1  - Supercomputer programmieren - ein besonderes Studienangebot in Jülich
JF  - Junge Wissenschaft. 27 (2012), H. 94
Y1  - 2012
SN  - 0179-8529
SP  - 12
EP  - 14
PB  - -
ER  - 
TY  - JOUR
A1  - Gutheil, Inge
A1  - Berg, Tommy
A1  - Grotendorst, Johannes
T1  - Performance Analysis of Parallel Eigensolvers of two Libraries on BlueGene/P
JF  - Journal of Mathematics and Systems Science
N2  - 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.
KW  - performance analysis
KW  - Elemental
KW  - ScaLAPACK
KW  - eigensolvers
KW  - Numerical linear algebra
Y1  - 2012
U6  - http://dx.doi.org/10.17265/2159-5291/2012.04.003
SN  - 2159-5291
VL  - 2
IS  - 4
SP  - 231
EP  - 236
PB  - David Publishing
CY  - Libertyville
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
A1  - Jansen, Paul
A1  - Schoberth, Siegfried
T1  - On Solving the McConnell Equations in Biochemistry / Grotendorst, Johannes ; Jansen, Paul ; Schoberth, Siegfried
JF  - MapleTech. 1 (1993)
Y1  - 1993
SN  - 1061-5733
N1  - zgl. Technical Report KFA-ZAM-IB-9314 ; The Maple Technical Newsletter
SP  - 56
EP  - 62
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
T1  - On calculating the rate of linear convergence of non-linear transformed sequences
JF  - Proceeding SNC '11 Proceedings of the 2011 International Workshop on Symbolic-Numeric Computation
Y1  - 2011
SN  - 978-1-4503-0515-0
SP  - 24
EP  - 33
PB  - ACM
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
A1  - Scott, Tony C.
A1  - Aubert-Frécon, Monique
T1  - New Approach for the Electronic Energies of the Hydrogen Molecular Ion / Scott, Tony C. ; Aubert-Frécon, Monique ; Grotendorst, Johannes
JF  - Chemical Physics. 324 (2006), H. 2/3
Y1  - 2006
SN  - 0301-0104
SP  - 323
EP  - 338
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
T1  - Maple programs for converting series expansions to rational functions using the Levin transformation automatic generation of FORTRAN functions for numerical applications
JF  - Computer Physics Communications. 55 (1991), H. 3
Y1  - 1991
SN  - 0010-4655
SP  - 325
EP  - 335
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
T1  - IAS Winter School: Hierarchical Methods for Dynamics in Complex Molecular Systems
JF  - Innovatives Supercomputing in Deutschland : inSiDE. 10 (2012), H. 1
Y1  - 2012
SP  - 104
PB  - -
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
A1  - Scott, Tony C.
A1  - Aubert-Frécon, Monique
A1  - Andrae, D.
T1  - Exchange Energy for Two-Active-Electron Diatomic Systems within the Surface Integral Method / Scott,T. C .; Aubert-Frécon, M. ; Andrae, D. ; Grotendorst, J. ; Morgan III, J. D. ; Glasser, M. L.
JF  - Applicable Algebra in Engineering, Communication and Computing. 15 (2004), H. 2
Y1  - 2004
SN  - 0938-1279
N1  - zugl. Technical Report FZJ-ZAM-IB-2004-02, April 2004, 24 pages
SP  - 101
EP  - 128
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
A1  - Schoberth, S. M.
A1  - Chapman, B. E.
A1  - Kuchel, P. W.
T1  - Ethanol Transport in Zymomonas mobilis Measured by Using in Vivo Nuclear Magnetic Resonance Spin Transfer / Schoberth, S. M. ; Chapman, B. E. ; Kuchel, P. W. ; Wittig, R. M. ; Grotendorst, Johannes ; Jansen, Paul ; Graaf, A. A. de
JF  - Journal of Bacteriology. 178 (1996), H. 6
Y1  - 1996
SN  - 0021-9193
SP  - 1756
EP  - 1761
ER  - 
TY  - JOUR
A1  - Grotendorst, Johannes
A1  - Kless, A.
A1  - Eitrich, T.
T1  - Data Mining in F & E / Kless, A. ; Eitrich, T. ; Meyer, W. ; Grotendorst, J.
JF  - BioWorld: Magazin für Molekularbiologische und Biotechnologische Applikationen. 9 (2004), H. 2
Y1  - 2004
SN  - 1424-8514
SP  - 22
EP  - 23
ER  -