Extracting a Subset of Read Sequences

Using the `-q' option, you can make a mapping file with only the reads from one of the read files. The read file is specified by its number in the input mapping file. If reads are interleaved, the output file will refer to the two interleaved files instead of just one file.

This is for example useful if you wish to study how the reads from a particular experiment behaved although the full mapping contains reads from several experiments.