Extracting Topics from Texts Based on Situations

To understand text, we must relate it with specified situations. This paper, on the basis of such an idea, discusses how the things that a text describes and the situation that the text relates to are expressed in a computer and how the topic of a text is extracted. The topic of a piece of writing is the central idea of it. People not only care for what it expresses, but also care for the most important idea of it. Therefore, if each piece of writing has a marked topic, then retrieval rate and retrieval precision of writings can be increased to a great extent. In computers, a piece o