CT numbers Ω A→B , which quantify electron flow from A to B upon excitation, are one such atomic partition. Arranged in the form of a matrix Ω, these quantities provides a simple visual representation of the transition density T (r hole , r elec ), a quantity that has occassionally been described as an "exciton wave function". Heat maps of the matrix Ω provide an easy way to distinguish localized versus delocalized excited states. This method can distinguish between delocalization caused by excitonic coupling between chromophores, versus delocalization due to charge separation; these possibilities are not mutually exclusive but also not equivalent. In multichromophore systems including conjugated polymers and crystalline acenes, this analysis exposes qualitative differences in the low-energy states obtained using different exchange-correlation functionals.