Details of good flow maps
- number of flow overlaps should be minimized;
– sharp bends and excessively asymmetric flows should be avoided;
– acute intersection angles should be avoided;
– flows must not pass under unconnected nodes;
– flows should be radially arranged around nodes;
– quantity is best represented by scaled flow width;
– flow direction is best indicated with arrowheads;
– arrowheads should be scaled with flow width, but arrowheads for thin flows - should be enlarged; and
– overlaps between arrowheads and flows should be avoided.
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