As a main composition and kernel problem of the digital earth,information city has been concerned and become a hot issue in present research.

Urban information is characterized by its condensation, spreading and share.

According to comparisons and analyses among the results,get a best combination urban information of Beijing City with the merging method of PCA,and give a theoretic appraise to the results.

The Study on City Information and Development of Urban Economy;

The development of Internet offered safeguard to realize city information of China.

As the extension and dissimilation of traditional entity space, the issue of informational city space is unavailable research object in the subject of architecture and urban design.

Based on Rough-set theory,problems of uncertain information and generous data in urban communications network construction are solved against spatial data processing of urban information.

This paper discusses the resolution of the problems of uncertain information and generous data of urban information systems based on information entropy and Rough-set theory, which research on spatial date processing of urban information.

This paper aims to resolve problems of uncertain information and generous data of urban information systems based on Rough-set theory, and spatial date processing of urban information.

Under the city informationization strategy background,it has the vital significance and the practical value to rethink and realize the public library s own function and use.

In this paper,the concept of city informationization is outlined,and the idea that city informationization and digital city have the same meaning is shared by the author.