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README.md

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+# gv2adj
+gv2adj computes adjacency matrices (either weighted or unweighted) for Graphviz
+graphs (both directed and undirected).
+
+## Usage
+To get the adjacency matrix of a graph in `graph.gv`:
+```
+gv2adj -f graph.gv
+```
+
+To get the matrix, but using the values stored in the `len` attribute as edge weights:
+```
+gv2adj -f graph.gv --weight-attr len
+```
+
+Say the nodes in the graph are named `foo`, `bar`, and `baz`. To order the rows and columns of the matrix so they correspond to `bar`, `baz`, `foo`:
+```
+gv2adj -f graph.gv --order bar,baz,foo
+```
+
+## Quirks
+* If the `--weight-attr` flag is supplied, but an edge does not have the given
+  attribute, NaN will be output for that edge.
+* If there are multiple edges going from node `a` to node `b`, the matrix entry
+  will be the sum of the two.