Geodesic
A class of optimally conditioned block $2\times2$ matrices
Zapiski Nauchnykh Seminarov POMI, Computational methods and algorithms. Part XV, Tome 284 (2002), pp. 64-76

Voir la notice de l'article provenant de la source Math-Net.Ru

A block $2\times2$ Hermitian positive-definite (h.p.d.) matrix is called equilibrated if its diagonal blocks coincide with the corresponding blocks of its inverse. It is demonstrated that any block $2\times2$ h.p.d. matrix is block diagonally similar to an equilibrated matrix, and any equilibrated matrix is optimally conditioned. Other properties of equilibrated matrices are also established. 
@article{ZNSL_2002_284_a4,
     author = {L. Yu. Kolotilina},
     title = {A class of optimally conditioned block $2\times2$ matrices},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {64--76},
     publisher = {mathdoc},
     volume = {284},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2002_284_a4/}
}
TY  - JOUR
AU  - L. Yu. Kolotilina
TI  - A class of optimally conditioned block $2\times2$ matrices
JO  - Zapiski Nauchnykh Seminarov POMI
PY  - 2002
SP  - 64
EP  - 76
VL  - 284
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/ZNSL_2002_284_a4/
LA  - ru
ID  - ZNSL_2002_284_a4
ER  - 
%0 Journal Article
%A L. Yu. Kolotilina
%T A class of optimally conditioned block $2\times2$ matrices
%J Zapiski Nauchnykh Seminarov POMI
%D 2002
%P 64-76
%V 284
%I mathdoc
%U http://geodesic.mathdoc.fr/item/ZNSL_2002_284_a4/
%G ru
%F ZNSL_2002_284_a4
L. Yu. Kolotilina. A class of optimally conditioned block $2\times2$ matrices. Zapiski Nauchnykh Seminarov POMI, Computational methods and algorithms. Part XV, Tome 284 (2002), pp. 64-76. http://geodesic.mathdoc.fr/item/ZNSL_2002_284_a4/