1. Editing and management functions of spatial data
Editing and managing spatial data is one of the basic functions of GIS software. ArcGIS has powerful data editing, version management, data sharing and enterprise-level data management functions, as well as spatial data collection, spatial database creation, topological relationship creation and management functions.
From the basic data management function, ArcGIS geodatabase spatial database can be understood as a collection of various types of geographic data sets stored in the same location, and its storage location can be a folder (local), an Access database or the same multi-user relational database management system (DBMS), which supports Oracle, Microsoft SQL Sever, PostgreSQL, Informix and IBM DB2.
File geodatabase is another kind of geodatabase in ArcGIS, which stores data sets in the form of folders in the computer. Each data set is stored as a file with the file size of 1TB, which supports cross-platform use and can also be compressed and decrypted.
File geographic data and personal geographic database are specially designed to support the complete information model of geographic database, including topological structure, grid directory, network data, terrain data set, address locator and so on. Neither database supports version management of version geodatabases.
ArcSDE geodatabases are designed for database management of multi-user geodatabases, and there are no restrictions on the size and number of users. If you need to use historical archiving, copy data, access simple data using SQL, or edit data at the same time without locking, you can use an ArcSDE geodatabase. It also supports mainstream DBMS such as Oracle, Microsoft SQL Sever, PostgreSQL, Informix and IBM DB2.
Of course, ArcGIS has a powerful basic data editing function, which will be introduced in detail in the next chapter.
For developers, the geodatabase API in ArcObjects (AO) can well control all types of geodatabases and other types of GIS data, and provide all functions from simple database creation and data query to advanced data collection structure (network, topology, etc.). ) and advanced geodatabase functions, such as version management, database replication and other APIs. Using AO API, developers can not only customize the functions in existing desktop products (ArcGIS Desktop), but also develop independent applications.
ArcSDAPI provides developers with the ability to directly control ArcSDE geodatabases.
2. Representation and advanced mapping functions
ArcGIS platform has a complete map production system, including map symbolization, map labeling, map editing, map output and printing. ArcGIS 10 has made many improvements in cartography, which are described in detail in 1.3 "New Functions of ArcGIS 10".
3. Geoprocessing function
Geoprocessing is based on data transformation. In ArcGIS, geoprocessing contains hundreds of spatial processing tools, which are used to perform various operations on datasets to generate new datasets. ArcGIS provides a model builder dialog box to support the design of operation processes composed of these tools, so that various models can be designed to realize automation and perform analysis of complex problems.
4. Spatial analysis and other extension modules.
Spatial analysis is the most distinctive part of GIS. In fact, spatial analysis is a part of data geographic processing. However, due to its support for rich and complex operations and the integration of multiple independent information sources, ArcGIS regards it as an independent extension module. Based on the spatial processing framework of visual modeling environment of ArcToolbox and Modelbuilder, the spatial analysis function can get rich and varied analysis and processing results.
In view of its extensive functions, the fifth chapter will introduce the details of this functional module independently.
5.3D visualization and analysis extension module
Raster data is an important source of GIS data, which is obtained by grid data collectors such as satellites and airplanes. In addition, digital elevation model, scanned paper map and thematic raster data are also important sources of raster data.
ArcGIS can manage, process, publish and use images, such as two-dimensional integrated image display and browsing, raster image data storage, cataloging, processing and distribution, image analysis and dynamic processing, image service publishing and map caching.
Three-dimensional visualization and analysis is one of the important development directions of GIS application at present, and it is also one of the hot technologies.
In addition to the basic GIS functions described above, ArcGIS also has the functions of application platform enterprise GIS, CAD system integration and integration, popular cloud computing technology and so on. This book focuses on the first five basic functions.