4.4.1 Map

The Map  type is the data type consisting of a key and an ObjectRef  as a set. ObjectRef  designates a pointer to any data types that is an Object , such as Matrix , Vector  or Source . Since HARK   provides a speech recognition function, processing is performed for each utterance. In such cases with processing for each utterance, Map<int, ObjectRef>  with an utterance ID (sound source ID) as a key is used. For example, the output of GHDSS  (sound source separation) is a Map<int, ObjectRef>  with an utterance ID as a key, and a pointer to a Vector< complex >  which contains the spectrum of the separated utterance is stored in ObjectRef . MatrixToMap  is for connecting such nodes with nodes that perform communication based on Matrix . Matrix  is used before sound source tracking processing, and Map  is used afterwards.