  The new and growing field of Quantitative Dependency Syntax has emerged at
the crossroads between Dependency Syntax and Quantitative Linguistics. One of
the main concerns in this field is the statistical patterns of syntactic
dependency structures. These structures, grouped in treebanks, are the source
for statistical analyses in these and related areas; dozens of scores devised
over the years are the tools of a new industry to search for patterns and
perform other sorts of analyses. The plethora of such metrics and their
increasing complexity require sharing the source code of the programs used to
perform such analyses. However, such code is not often shared with the
scientific community or is tested following unknown standards. Here we present
a new open-source tool, the Linear Arrangement Library (LAL), which caters to
the needs of, especially, inexperienced programmers. This tool enables the
calculation of these metrics on single syntactic dependency structures,
treebanks, and collection of treebanks, grounded on ease of use and yet with
great flexibility. LAL has been designed to be efficient, easy to use (while
satisfying the needs of all levels of programming expertise), reliable (thanks
to thorough testing), and to unite research from different traditions,
geographic areas, and research fields.
