a50 - a simple tool for graphing genome coverage and fragmentation.
Reads files of contigs, and compares them by plotting each as a line in a graph.
The x-axis represents contig number, the y-axis represents total (cumulative) size.
An ideal assembly contains a few, large contigs, thus this curve should rise steeply, and
stop early (but at the expected genome size). Conversely, a poor assembly consisting of
many small fragments will have a less steep curve extending far to the right.
The graphs produced by a50 gives a simple and easy to grasp comparison between assemblies,
and yet produces a more detailed and informative view than the usual metrics like largest
contig size or N50.
The Darcs repository is at http://malde.org/~ketil/biohaskell/a50.