Research on Mapping Mechanism of Learning Expression

In this paper, we propose a description of Machine Learning System (MLS) which is based on the category theory in order to study mapping mechanism of the learning expression. And a detailed instance is provided. This is that Decision Tree Learning (DTL) can be denoted based on category theory. In addition, we prove that the machine learning system is indeed a category, and propose the learning expression and the mapping mechanism of the learning expression based on category theory. Also we describe the proof and verify the mechanism.