C. Vector operations
The vector class provided in the PHP PEAR package [26] is used as a dependency for the complex number class as some of the operations require values to be defined as vectors.
D. Network data definition
The network data is defined using an XML format document which is parsed and read into memory by the PHP library.
The network is defined using different custom tags for the elements, the buses and lines.
Loads and generators are defined based on the direction of power flow.
E. Dependency management and library block diagram.
The dependencies for any study to be carried out are included in the program before the operations are run.
Figure 3 illustrates the dependencies and interrelationships of all components of the library in a block diagram