Besen, David K., authorMcConnell, Ross, advisorBohm, Wim, committee memberPeterson, Chris, committee member2019-06-142019-06-142019https://hdl.handle.net/10217/195343A threshold tolerance graph is a graph where each vertex v is assigned a weight wv and a tolerance tv, and there is an edge between two vertices vx and vy if and only if wx + wy ≥ min(tx,ty). A co-TT graph is the complement of a threshold tolerance graph. Recognition of these graphs can be done in O(n2) time; however no polynomial-time algorithm to identify isomorphisms between pairs of TT or co-TT graphs was previously known. We give an algorithm to identify these isomorphisms, which takes O(n2) time.born digitalmasters thesesengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Co-TT graphsisomorphismalgorithmsthreshold tolerance graphsgraph theoryText