Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-1 Course objectives This course will introduce you to ArcGIS and provide the foundation for you to become a successful ArcView, ArcEditor, or ArcInfo user. You will learn how to use ArcMap, ArcCatalog, and ArcToolbox and explore how these applications work together to provide a complete GIS software solution. The course covers fundamental GIS concepts as well as how to create, edit, and work with georeferenced spatial data. You will learn how to manipulate tabular data, query a GIS database, and present data clearly and efficiently using maps and charts. This course covers a variety of topics but may not include specific tools or concepts used in your applications. If you have questions about particular functionality that does not appear to be covered by this class, feel free to ask your instructor. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-2 ArcGIS is the name used to identify ESRI’s flagship family of GIS products. ArcGIS includes client software, server software, and data components. ArcGIS itself is not a GIS application; rather, it is a system of software products, each servicing a specific need. Software products and applications When someone purchases an ArcGIS system, they license software products which include one or more software applications. Understanding the difference between products and applications is important in understanding how ArcGIS is structured, and how the topics covered in this training class relate to the system as a whole. For example, one group may license the ArcView software product, which includes the ArcMap, ArcCatalog, and ArcToolbox applications. Another group may license the ArcEditor software product, which includes the same three applications. After installing their respective products, both groups would find icons for the ArcMap, ArcCatalog, and ArcToolbox applications in their Start menus; neither would find an ArcView or ArcEditor icon. But upon running the applications, the ArcEditor group would find more useful buttons and menu choices than the ArcView group. In another example, a group who licenses the ArcSDE software product may install and use the ArcSDE, ArcSDE CAD Client, and ArcSDE for Coverages applications. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-3 Support resources ESRI’s primary resource for software support is the Online Support Center (OSC) at http://support.esri.com. From the OSC you can request assistance from ESRI Technical Support, interact with other ESRI software users, and even help yourself to technical information and downloads. Support resources are grouped by software product. When you click the name of a software product, a list of available resources expands below the name. In the graphic above, clicking the ArcGIS Desktop product name reveals links to technical articles, downloads, system requirements, and more. Downloads Software upgrades—also called service packs, patches, updates, and utilities—are ESRI- provided enhancements. These upgrades range from handy tools that facilitate common tasks to system upgrades that resolve bugs, improve performance, and add support for additional platforms. Unless otherwise stated in their descriptions, software upgrades are fully supported by ESRI Technical Support. In-depth technical papers discuss topics like system design, performance, and integration. Documents available through the Technical papers link are written by ESRI, and the recommendations they make are fully supported by ESRI Technical Support. The ArcScripts site is a repository of software utilities (scripts) supplied by the ESRI user community for the benefit of its peers. Here you will find ArcScripts, as these utilities are called, for most ESRI software products and customization environments, including ArcGIS VBA, Avenue, and AML. Download scripts anonymously, and create a free account to post tools to the archive. ArcScripts are provided as-is and are not supported by ESRI Technical Support. You may, however, purchase technical support for a per-incident fee. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-4 Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-5 Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-6 Definitions of a geographic information system can vary considerably. The definition provided here combines both the components and functions of a GIS. The components needed to perform GIS tasks include: People This is the most important component in a GIS. People must develop the procedures and define the tasks of the GIS. People can often overcome shortcomings in other components of the GIS, but the best software and computers in the world cannot compensate for the incompetence of people. Data The availability and accuracy of data can affect the results of any query or analysis. Hardware Hardware capabilities affect processing speed, ease of use, and the type of output available. Software This includes not only actual GIS software, but also various database, drawing, statistical, imaging, or other software. Procedures Analysis requires well-defined, consistent methods to produce accurate, reproducible results. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-7 Any GIS should be capable of the following fundamental operations in order to be useful for finding solutions to real-world problems. Capturing data A GIS must provide methods for inputting geographic (coordinate) and tabular (attribute) data. The more input methods available, the more versatile the GIS. Storing data There are two basic data models for geographic data storage: vector and raster. A GIS should be able to store geographic data in both models. Querying data A GIS must provide utilities for finding specific features based on location or attribute value. Analyzing data A GIS must be able to answer questions regarding the interaction of spatial relationships between multiple datasets. Displaying data A GIS must have tools for visualizing geographic features using a variety of symbology. Output A GIS must be able to display results in a variety of formats, such as maps, reports, and Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-8 graphs. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-8 Because the geographic database is the expensive and long-lived component of the GIS, data entry is an important consideration. ArcGIS integrates a variety of data types from a variety of sources, so it provides multiple data entry options. ArcGIS offers efficient data entry methods for automating paper maps and other nondigital data sources. To take advantage of the vast collection of geographically referenced data that already exists in digital format, ArcGIS provides the most comprehensive data conversion capability of any GIS on the market. ArcGIS software's integrative capabilities also allow data to be shared with other applications without the need for conversion. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-9 You can represent geographic features in vector or raster format. Vector data The vector data model represents geographic features much the same way maps do—using points, lines, and areas. An x,y (Cartesian) coordinate system references real-world locations. Raster data Instead of representing features by their x,y coordinates, the raster data model assigns values to cells that cover coordinate locations. Raster format is well suited to spatial analysis and is also appropriate for storing data collected in grid format. The amount of detail you can show for a particular feature depends on the size of the cells in the grid. This makes raster data inappropriate for applications where discrete boundaries must be known, such as parcel management. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-10 Identifying specific features One common type of GIS query is to determine what exists at a particular location. In this type of query, the user understands where the features of interest are, but wants to know what characteristics are associated with them. This can be accomplished with GIS because the spatial features are linked to the descriptive characteristics. Identifying features based on conditions Another type of GIS query is to determine the locations that satisfy certain conditions. In this case the user knows what characteristics are important and wants to find out where the features are that have those characteristics. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-11 You can perform analysis to obtain the answers to a particular question or find solutions to a particular problem. Geographic analysis usually involves more than one geographic dataset and requires the analyst to proceed through a series of steps to reach a result. Three common types of geographic analysis are: Proximity analysis • How many houses lie within 100 meters of this water main? • What is the total number of customers within 10 kilometers of this store? • What proportion of the alfalfa crop is within 500 meters of the well? To answer such questions, GIS technology uses a process called buffering to determine the proximity between features. Overlay analysis An overlay process combines the features of two layers to create a new layer that contains the attributes of both. This resulting layer can be analyzed to determine which features overlap, or to find out how much of a feature is in one or more areas. An overlay could be done to combine soil and vegetation layers to calculate the area of a certain vegetation type on a specific type of soil. Network analysis This type of analysis examines how linear features are connected and how easily resources can flow through them. Introduction to ArcGIS I (for ArcView 8, ArcEditor 8, and ArcInfo 8) Introduction 1-12 For many types of geographic operations, the end result is usually best visualized as a map or graph.