The program library is written in Fortran 90. While not an ideal language (it is not object-oriented, for example) it has considerable advantages over Fortran 77. These include a module facility which allows the grouping of related data and procedures into a single file, the ability to dynamically allocate storage and a handy syntax for array operations.
All program units in the DYNAMO library are grouped into modules. The modules are of several basic types which may be classified as follows:
A complete listing of the modules along with a brief description of their function and their public variables and procedures is available.
Most modules have been written from scratch but there are a few for which the code has been obtained elsewhere. In particular, subroutines for the semi-empirical calculations were taken from the public domain code of MOPAC. Attributions for other code taken from public domain sources may be found in the module descriptions.