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{{Short description|Node labeling problem in graph theory}}
In [[graph theory]], the '''graph bandwidth problem''' is to label the ''n'' vertices ''v<sub>i</sub>'' of a graph ''G'' with distinct integers ''f''(''v<sub>i</sub>'') so that the quantity <math>\max\{\,| f(v_i) - f(v_j)| : v_iv_j \in E \,\}</math> is minimized (''E'' is the edge set of ''G'').<ref>{{harv|Chinn|Chvátalová|Dewdney|Gibbs|1982}}</ref>
 
In [[graph theory]], the '''graph bandwidth problem''' is to label the ''{{mvar|n''}} [[Vertex (graph theory)|vertices]] ''{{mvar|v<{{sub>|i</sub>''}}}} of a [[Graph (discrete mathematics)|graph]] ''{{mvar|G''}} with distinct integers[[integer]]s ''{{tmath|f''(''v<sub>i</sub>''v_i)}} so that the quantity <math>\max\{\,| f(v_i) - f(v_j)| : v_iv_j \in E \,\}</math> is minimized (''{{mvar|E''}} is the edge set of ''{{mvar|G''}}).<ref>{{harv|Chinn|Chvátalová|Dewdney|Gibbs|1982}}</ref>
The problem may be visualized as placing the vertices of a graph at distinct integer points along the ''x''-axis so that the length of the longest edge is minimized. Such placement is called '''linear graph arrangement''', '''linear graph layout''' or '''linear graph placement'''.<ref name=feige/>
 
The '''weighted graph bandwidth problem''' is a [[generalization]] wherein the edges are assigned [[Graph (discrete mathematics)#Weighted_graph|weights]] ''{{mvar|w<{{sub>|ij</sub>''}}}} and the [[Loss function|cost function]] to be minimized is <math>\max\{\, w_{ij} |f(v_i) - f(v_j)| : v_iv_j \in E \,\}</math>.
 
In terms of matrices, the (unweighted) graph bandwidth is the minimal [[bandwidth (matrix theory)|bandwidth]] of a [[symmetric matrix]] which is an [[adjacency matrix]] of the graph.