This lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 1Geog 458: Map Sources and Errors January 13, 2006 Lab 1: Exploring data format Data format supported by ArcGIS There are many file types supported by ArcGIS, in addition to specific cartographic objects. A fundamental goal of ArcGIS is to work with all file-based data and Data Base Management Systems (DBMS) data. ArcGIS lets the user work with an extensive array of data sources. In this lab we will introduce you to what some of the many are. Among the more difficult tasks for the first time user of ArcGIS is keeping track of the object types, file types and directory structures. It is also important to understand how database structures are organized within a GIS so that you have a basic understanding of how you may search for and manipulate the data contained in the database. ArcGIS supports many different file formats. For example, you may need to use satellite imagery, or other compatible file types. For imagery, the following types are supported by the program: Format Extension(s) Arc Digitized Raster Graphics (ADRG) *.img or *.ovr Band Interleaved by Line (ESRI BIL), Band Interleaved by Pixel (ESRI BIP), Band Sequential (ESRI BSQ) *.bil, *.bip, or *.bsq Bitmap (BMP), Device-Independent Bitmap format (DIB), or Microsoft Windows Bitmap *.bmp Compressed ARC Digitized Raster Graphics (CADRG) no standard file extension Controlled Image Base (CIB) no standard file extension Digital Terrain Elevation Data (DTED Level 1 & 2), and Digital Elevation Model .dt1, .dem ER Mapper usually same as headerThis lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 2file without the *.ers extension Graphics Interchange Format (GIF) *.gif ERDAS 7.5 GIS *.gis ESRI GRID file format (ESRI GRID) Directory ESRI GRID Stack Directory ESRI GRID Stack file *.stk ERDAS IMAGINE file *.img JPEG File Interchange Format (JFIF) *.jpg, *.jpeg, *.jfif ERDAS 7.5 LAN *.lan Multiresolution Seamless Image Database (MrSID) *.sid Spatial Database Engine Raster file format (ArcSDE Raster) Stored in SDE database Tag Image File Format (GeoTIFF tags are supported) (TIFF) *.tif, *.tiff, *.tff ERDAS Raw *.raw Portable Network Graphics (PNG) *.png National Image Transfer Format (NITF) *.ntf Representing geography & data collection Start ArcMap (choose Start – All Programs – ArcGIS – ArcMap) Choose A new empty map and then click OK buttonThis lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 3 In your new map document, click the add data button and navigate to the c:\ESRI\ESRIDATA\Canada directory and select the rivers.shp file. Click “Add” to place it in your map document. The shapefile is one of the most basic types of object file structures used in ArcGIS. It might be useful to examine what some of these basic file types are all about. Rather than having you try to look at all of them, instead use the help pull down menu and, using the help index, search by topic first for “shapefiles, described.” When you click on it you will receive a wealth of information (probably more than you can digest in a single sitting). You should remember the help file for future reference as it addresses most questions that you can think of about the program, as long as you use the correct terminology. You should notice that shape files come in a number of types. Examine, for example, a point and a line. We will look at polygons in our review questions at the end of the lab. Relate this information to what you have learned in your class, especially regarding dimensionality, and how these forms of the shape file are developed (e.g. a line being composed of at least two point locations). You now have the ability to search for any number of file types or for other information as you need.This lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 4 Now that you have added the rivers.shp file to your map, think about the probable source of this information. Do you think that it was from surveyed data or input from an existing document? In other words is this collected through primary data capture or secondary data capture methods? Add another theme such as the province.shp. Again ask yourself whether this is created by direct measurements (e.g. remote sensing, survey) or this is input from paper maps?This lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 5 Examine the tables associated with the province.shp. To do this, right click on the province layer name in your map documents TOC, and select “Open attribute table.” You may have noticed that tabular database (attribute table) is linked to the graphics portion of the database in ArcGIS. Examine what information is available in the shape file. While it indicates the area, does it also include all of the point, line and polygon data as well? What does this suggest about the type of GIS you are working with (e.g. hybrid or integrated)? Hybrid GIS means that spatial data are not entirely integrated into attribute data, but rather are linked to attribute data through a common identifier. On the other hand, integrated GIS means that the whole information is integrated into one database without having to separate the graphic portions (point, line, polygon) from attribute data. Imagine that instead of provinces, each polygon is, for example, a soil polygon or a vegetation type. Think about the problems you might encounter while analyzing such maps.This lab is adapted from lab materials provided by Demers MN, 2005, Fundamentals of Geographic Information Systems, 3rd Edition, John Wiley & Sons. 6In ArcGIS there are three primary feature classes, which include points, lines and polygons. The fundamental difference between an ArcView shapefile and an ArcInfo coverage is that a shapefile contains only one feature class, and a coverage may contain all feature classes. In other words a shapefile may only be either a point, line, or polygon feature, whereas a polygon coverage for example contains points (label points), lines