Introduction to ArcView 3.2
Transcription
Introduction to ArcView 3.2
Startup Why are you here? What are your experiences? What are your major working/research topics? What do you want to learn? Introduction to Geographic information systems Description of a GIS GIS is a software tool: The software tool is a combination of a CAD-tool and a database management system that gives access to geographically referenced data ArcView 3.x Two developing lines in ArcView: ArcView 3.x and ArcView 8.x and following ArcView 3.x is „fading out“ – Version 3.3 was last updated in 2004 ArcView 3.x will be supported also the next 4-5 years ArcView 8.x was developed 2001, the new version is 9.1, in autumn 2006 version 9.2 is expected to be released ArcView 3.x is more common than ArcView 8.x or 9.x ArcView 3.x From the printed map to a digital map: Digitizing concepts in ArcView Two possibilities to get a digital vector map: • Using a digitizer • Digitizing at the monitor Three steps to digitize a map at the monitor: • Scanning • Georeferencing • Digitizing Scanning Several maps are needed to get a good (hydro-)geological map: - Scan it coloured, decrease colour depth to black/white - Resolution 300 dpi - Be sure, that the clipping covers more than the thematical map Georeferencing images Georeferencing is not easy with ArcView 3.x: • For every *.tif-file a *.tfw-file is needed. Georeferencing images • Choose at least two points in the map to join pixel coordinates and real world coordinates. Real world coordinates from the analog map or from the measured grid. Quantum GIS Open the georeferenced image file in ArcView 3.x: Aquifer types: Classification international standard legend From: Struckmeier & Margat (1995) Aquifer types: Classification international standard legend From: Struckmeier & Margat (1995) Digitizing maps Digitizing maps: Concepts Entities of geographical data: • Points • Lines • Polygones Non-topological GIS: No connection between points, lines and polygones. Attributes: Relational database structure possible. Digitizing points Choose „View“ – „New Theme“ – „Point“, set path and name Theme must be - active, - visible and - ready to start edit ! Points can be digitized after pushing the button Attributing points To attribute the points, it‘s easy to open the table aside of the view window and add the attributes/fields: It‘s good to use relate-tables e.g. for tectonical data Digitizing lines Choose „View“ – „New Theme“ – „Line“, set path and name Theme must be active, visible and ready to start edit! Lines can be digitized after pushing button If a line should snap to another one, intersection of lines should be used Digitizing polygons A bit tricky: Choose „View“ – „New Theme“ – „polygon“, set path and name Theme must be active, visible and ready to start edit! Because we don‘t need squares or circles, we use the following button Digitizing polygons Polygons have to be adjacent to each other! Three ways in digitizing: 1. „Create new polygon“ 2. Append new polygon adjacent to another 3. Create line to split polygon Digitizing polygons The borders of polygons shouldn‘t be corrected because ArcView is a non-topological GIS and every border is internally constructed by two lines. Result: By adjusting a vertex an overlap or a gap will be created! Solution: Mark both polygons, use button to move vertices, click to the vertex (attention, don‘t move!!!) and after that move the vertex Digitizing polygons Another problem: Digitizing of isle-polygons Polygons are digitized overlapping, then chosen by „Select feature“ button and then cut by using „Edit“->“Subtract features“ Digitizing polygons Work with relate tables: - less problems in attributing while digitizing - easy change of attribute data - use of more sophisticated interpretation and further utilization of data Visualizing maps Visualizing our data: A short view at the legend editor • Open the shape-file and double-click the theme in the View-window. • Use the Legend editor to show classifications. • Find out about changes in colours, line thickness, symbols in the Symbol editor. Symbols and colours: Legend editor Legend can be changed by doubleclicking the Table of Content Legend Editor is opened, type and classification can be changed Symbols and colours: Symbol editor Change symbols: Doubleclick the Symbol Symbol Editor is opened, Fill, Pen, Marker, Font and Colour of the symbol can be changed Symbols and colours: Additional symbols Additional palettes: Use the Palette Manager Standard extensions: e activat Explore the extensions! More extensions: Extensions are saved in C:\ESRI\AV_GIS30\ARCVIEW\EXT32 More extensions are saved in C:\ESRI\AV_GIS30\ARCVIEW\Samples\ext Even more extensions are available on • ESRI homepage • www.seminolecountyfl.gov/gis/extents.asp • etc. Load extensions in ArcView: To use these extensions: Copy the *.avx-file to the C:\ESRI\AV_GIS30\ARCVIEW\EXT32 folder Some extensions are very expensive (but also very useful): Spatial analyst: Handle raster data in ArcView 3D Analyst: Visualize raster data in 3D ArcPress: Raster-Image Processor (RIP) used for fast printing Scripting Language in ArcView 3.x: Avenue Two very important examples: Addxycoo.ave (add X,Y coordinates to a point theme) Shp2gen.ave (create a generate file from a shape file) Also useful: Calcacre.ave (calculate areas) There are dozens of scripts (without a description) Scripting Language in ArcView 3.x: Avenue How to use scripts: In the project window choose the “scripts” button Scripting Language in ArcView 3.x: Avenue Most of the scripts are in the directory: C:\ESRI\AV_GIS30\ARCVIEW\Samples\scripts Scripting Language in ArcView 3.x: Avenue Scripts have to be “compiled”: Scripting Language in ArcView 3.x: Avenue After compiling click to the view window, click on the theme the script refers to (activate it!) and then run the script Scripting Language in ArcView 3.x: Avenue There are thousands of ArcView 3.x scripts in the internet available (free and with a description). Selections and querrying Querrying values in ArcView 3.x Identify-button: Cick to the feature: Selecting values, open attribute table in ArcView 3.x Querry builder in ArcView 3.x It‘s also possible to use the querry builder for a table Advanced selections in ArcView 3.x Spatial/geometrical selections: Select from one theme, „Select by theme“ from another theme Advanced selections in ArcView 3.x Spatial/geometrical selections: Advanced selections in ArcView 3.x Also possible with lines: Constructing groundwater contours Hydrological Triangle: Constructing groundwater contours Hydrological Triangle: Layout in ArcView 3.x Principles A map consists of: • The map itself with a grid showing the geographical reference • A legend • A scale bar • A north arrow A few rules for map composition: • Have a look at the copyright and tell, where the data come from • Isolines should be annotated with numbers foot downhill • Label shouldn‘t cover other objects • More than 12 colours are very hard to distinguish Techniques In the layout: • Set „Layout“ – „Page setup“ to centimeters • Set „Layout“ – „Properties“ to a grid spacing of 0.1 cm Techniques Specify • Scale of the View • Outline of the View • Scale bar • North arrow • Fonts in the Symbol Window Graticules and GRIDs Add „Graticules and Grids“ with a button. Use „wizard“.