The shortest yet efficient implementation of PrefixSpan in Scala. You can find the Python 3 version here.

Usage

scala PrefixSpan (frequent | top-k) <threshold> [<minlen>=1] [<maxlen>=maxint]

• Sequences are read from standard input. Each sequence is integers separated by space, like this example:

0 1 2 3 4
1 1 1 3 4
2 1 2 2 0
1 1 1 2 2

• The patterns and their respective frequencies are printed to standard output.

Features

Outputs traditional single-item sequential patterns, where gaps are allowed between items.

• Mining top-k patterns is also supported, with respective optimizations.
• You can also limit the length of mined patterns. Note that setting maximum pattern length properly can significantly speedup the algorithm.