I have a question about exactly how the multiplicity of an edge in the de Bruijn graph is determined. It seems that the multiplicity is simply the number of reads which covers an edge.

However, this seems to not be the complete story. Later, the paper goes on to discuss x,y-detachment. At the bottom of page 9752, left column, they state:

My assumption here is that each of these paths is a read. Thus, there are three reads. Thus, the multiplicity of x would always be three. In other words, this second condition can never occur in a graph that was created from a set of reads, because there would be three visits (multiplicity three), rather than two visits.

What am I missing?

The paper is here.

However, this seems to not be the complete story. Later, the paper goes on to discuss x,y-detachment. At the bottom of page 9752, left column, they state:

The second condition implies that the Eulerian Superpath

Problem has no solution, because P, Px,y1, and Px,y2 impose

three different scenarios for just two visits of the edge x.

Problem has no solution, because P, Px,y1, and Px,y2 impose

three different scenarios for just two visits of the edge x.

My assumption here is that each of these paths is a read. Thus, there are three reads. Thus, the multiplicity of x would always be three. In other words, this second condition can never occur in a graph that was created from a set of reads, because there would be three visits (multiplicity three), rather than two visits.

What am I missing?

The paper is here.

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