edge_upper -i in1 -o out1.file out1.mr
edge_upper -i tmp.matrix -o mre
This is a named command which eliminates duplicate and self-edges from a graph. A duplicate edge is when both (Vi,Vj) or (Vj,Vi) appear in the edge list. A self-edge is when (Vi,Vi) appears.
See the named command doc page for various ways in which the -i inputs and -o outputs for a named command can be specified.
In1 stores a set of edges, which may have duplicates or self edges. The input is unchanged by this command.
Out1 will store the edges of a new graph which has the duplicates and self edges removed. In the new graph, Vi < Vj for every edge, so it also represents the non-zeroes of an upper-triangular matrix.