# Partial covers of graphs

Discussiones Mathematicae Graph Theory (2002)

- Volume: 22, Issue: 1, page 89-99
- ISSN: 2083-5892

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topJirí Fiala, and Jan Kratochvíl. "Partial covers of graphs." Discussiones Mathematicae Graph Theory 22.1 (2002): 89-99. <http://eudml.org/doc/270598>.

@article{JiríFiala2002,

abstract = {Given graphs G and H, a mapping f:V(G) → V(H) is a homomorphism if (f(u),f(v)) is an edge of H for every edge (u,v) of G. In this paper, we initiate the study of computational complexity of locally injective homomorphisms called partial covers of graphs. We motivate the study of partial covers by showing a correspondence to generalized (2,1)-colorings of graphs, the notion stemming from a practical problem of assigning frequencies to transmitters without interference. We compare the problems of deciding existence of partial covers and of full covers (locally bijective homomorphisms), which were previously studied.},

author = {Jirí Fiala, Jan Kratochvíl},

journal = {Discussiones Mathematicae Graph Theory},

keywords = {covering projection; computational complexity; graph homomorphism; lambda coloring},

language = {eng},

number = {1},

pages = {89-99},

title = {Partial covers of graphs},

url = {http://eudml.org/doc/270598},

volume = {22},

year = {2002},

}

TY - JOUR

AU - Jirí Fiala

AU - Jan Kratochvíl

TI - Partial covers of graphs

JO - Discussiones Mathematicae Graph Theory

PY - 2002

VL - 22

IS - 1

SP - 89

EP - 99

AB - Given graphs G and H, a mapping f:V(G) → V(H) is a homomorphism if (f(u),f(v)) is an edge of H for every edge (u,v) of G. In this paper, we initiate the study of computational complexity of locally injective homomorphisms called partial covers of graphs. We motivate the study of partial covers by showing a correspondence to generalized (2,1)-colorings of graphs, the notion stemming from a practical problem of assigning frequencies to transmitters without interference. We compare the problems of deciding existence of partial covers and of full covers (locally bijective homomorphisms), which were previously studied.

LA - eng

KW - covering projection; computational complexity; graph homomorphism; lambda coloring

UR - http://eudml.org/doc/270598

ER -

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