Unicast-Uniprior Index Coding Problems: Minrank and Criticality

Niranjana Ambadi

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arXiv · 1901.04926

Unicast-Uniprior Index Coding Problems: Minrank and Criticality

Niranjana Ambadi

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Abstract

An index coding problem is called unicast-uniprior when each receiver demands a unique subset of messages while knowing another unique subset of messages apriori as side-information. In this work, we give an algorithm to compute the minrank of a unicast-uniprior problem. The proposed algorithm greatly simplifies the computation of minrank for unicast-uniprior problem settings, over the existing method whose complexity is exponential in the number of messages. First, we establish some properties that are exclusive to the fitting matrix of a unicast-uniprior problem. Further, these properties are used to lay down the algorithm that computes the minrank.

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Niranjana Ambadi. 2019-01-15. Unicast-Uniprior Index Coding Problems: Minrank and Criticality. https://arxiv.org/abs/1901.04926

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