THE HONG KONG POLYTECHNIC UNIVERSITY DEPARTMENT OF LAND SURVEYING & GEO-INFORMATICS LSGI521 PRINCIPLES OF GIS

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1 THE HONG KONG POLYTECHNIC UNIVERSITY DEPARTMENT OF LAND SURVEYING & GEO-INFORMATICS LSGI521 PRINCIPLES OF GIS Student name: Student ID:

2 Table of Content Working with files, folders, various software and hardware.2 Exercise 1 Data preparation for LIC Basemap... 6 A. Import data from e00 to coverage... 6 B. Merge data... 7 Exercise 2 Displaying data and Querying data... 8 A. Symbolize your data... 8 B. Label your data C. Display the attributes of a particular feature on a view D. Select features with the mouse E. Select features with graphics F. Select features by querying attribute table G. Find features by spatial query Exercise 3 - Editing data A. Start an edit session B. Set the snapping environment C. Skills of working with mouse D. Digitize features E. Stop editing and save you work F. Calculate Value Exercise 4 - Plotting your map A. Create a layout B. Control scale C. Add elements on the map D. Make grid line Exercise 5 - Making 3D TIN model and terrain analysis A. Create TIN model B. 3D Visualization C. Analysis slope aspect with TIN model Assignments to be submitted

3 Working with files, folders, various software and hardware How to get the lecture notes and other related facilities 1. Using computers inside LSGI computing labs, Start Menu LSGI, PolyU Directory Homework Submit- Students paste any online submission. Local D Drive - Access the local D drive of your occupied computer. Network_Home_Folders_(All students) Students keep any storage inside the LSGI server. Teaching Materials Students download any teaching materials here. Please click LSGI521 for downloading both the lecture notes and lab handouts. Homework Submit Local_D_Drive Network_Home_Folders_ (All students) Teaching OR 2. Using Intranet of LSGI website Go to LSGI Website and click Intranet Student. After the insertion of username and password, please click I agree & answer truthfully for proceeding. 2

4 Come to a new page and select Download Resources, click Teaching Materials. You can similarly retrieve to the above materials. How to access your own student directory In Room FG311/FG307, every time you finish doing something and before you leave the room, it is extremely important and safe to save the file (i.e. the folder and/or data you created) into your own student directory in both ways: Start Programs LSGI, PolyU Directory Local D drive. You can save your files temporarily in d:\00-temp\. Here, you ll create a folder with your own student no. Once you finish every practical, please backup your files into Student Storage inside LSGI server or MYDRIVE system every time. 3

5 After you have inputted the required username and password to access the MYDRIVE, you may click to this page Access mystore for storage. How to open ArcView 9.2 Go to start -> All Programs -> ArcGIS. ArcView 9.2 is composed of ArcCatalog, ArcMap, ArcToolbox and so on. ArcCatalog is used for: Browse your graphical or textual data Manage and define your data Set and view metadata ArcMap is used for perfoming map-based tasks such as mapping, editing, queries, analysis, graphing and reporting. ArcToolbox is used for data conversion and advanced geoprocessing functions. 4

6 In the exercise, you will use ArcCatalog and ArcMap frequently. You can try to browse data in ArcCatalog and add data into ArcMap in this lesson. How to submit assignments You should submit your assignments before deadline either using Homework_Submit\LSGI521\ Submission No \Stud ID, or using LSGI website with same path. Practical for Continuous Assessment: 50% 5

7 Exercise 1 Data preparation for LIC Basemap In this exercise, you will learn how to import Basemap data into ArcView 9.2 software. Since Hong Kong basemap data supplied by the Government (Land Information Centre, Survey and Mapping Office of Lands Department) is provided in ArcInfo export format e00, data should be converted from e00 to coverage format and therefore you can view data in this software. A. Import data from e00 to coverage Please download the Basemap folder inside the lab folder of LSGI521teaching materials. In this part, you learn to convert e00 files into ArcInfo coverage format for BLDG and CONT layers. And you have to convert total 14 tiles (11swa, 11swb, 11swc, 11swd, 11sea, 11seb, 11sec, 11sed, 15nwa, 15nwb, 15nea, 15neb, 15nec, 15ned). Inside it, there are 13 files showing the topographic information in Hong Kong. These tiles are B5000 Hong Kong digital maps in a scale of 1:5000, supplied by the Lands Department. The reason why you do such data conversion is the e00 cannot be directly read by the ArcGIS software. 1. Copy e00 files in teaching materials server. 2. Create a new folder to store coverage files temporarily in local d drive, e.g d:\00-temp\studid\lsgi521\coverage\ 3. In ArcCatalog, click the View menu, click Toolbars, then click the ArcView 8.x Tools toolbar. 4. Click the Conversion tools drop-down menu and click Import from Interchange File. (It is a conversion program that converts an ARC/INFO interchange file created on any other operating system into an ARC/INFO 7.x coverage. If you receive ARC/INFO data in interchange format you can use ArcToolbox to convert it to a data source in a format that can be added to map document in ArcView 9.2). 5. Click the Input file Browse button and navigate to the.e00 file to be imported. 6. Click the.e00 file and click Open. 7. Click the Output dataset Browse button and navigate to the location for the output dataset to be stored, then click Save. 8. Click OK. 6

8 9. Run in batch mode The utility in ArcToolbox can be run in batch mode which is faster way to convert many tiles. You can write batch file to automatically run the utility. In the popup box, you can click on batch button and then a table appears. You can convert more than one file here. Click on Add Row button you can define the paths for export one more file. 10. Using the same procedure in point 4 to export building data in all tiles. After you finished setting the paths for all data, click OK. B. Merge data In this part, you will learn to append the features of several layers into an ArcMap environment. After conversion, you have to merge building and contour layers into identical shapefiles. 1. Start ArcCatalog. 2. Open the toolbox window and choose the Merge General tool in the Data Management toolbox. 3. Choose the layers with the same feature classes that are going to be part of the new feature class, i.e. add all building layers of 14 tiles. 4. Define and create the output name. Run the function. 14 layers are merged into one shapefile. 5. Do the same steps for contour layers. 7

9 Exercise 2 Displaying data and Querying data In this exercise, you will learn the basic functions of ArcView 9.2 software. It involves representing our data by different color and symbols and querying spatial data by attribute table and their spatial relationships. Please download the Coverage folder into your local D drive. A. Symbolize your data You will learn how to symbolize your data involves choosing colors and symbols that will represent features. It also involves grouping or classifying features according to their attribute values. Drawing a layer using a single symbol 1. Add wanchai_road.shp in ArcMap. 2. In the table of contents, right click wanchai_road layer you want to draw with a single symbol and click properties. 3. Click the Symbology tab. 4. Click Features. Because Single symbol is the only option, ArcMap automatically selects it. 5. Click the Symbol button to change the symbol. 6. In the Symbol Selector dialog box, click a new symbol or change specific properties, e.g. color and width of the symbol. 7. Click OK on the Symbol Selector dialog box. 8. Click OK. 8

10 Drawing a layer showing unique values 1. Add bldg.shp in ArcMap. 2. In the table of contents, right click the building layer you want to draw showing unique values and click Properties. 3. Click the Symbology tab. 4. Click Categories. ArcMap automatically selects the Unique values option. 5. Click the Value Field dropdown arrow and select Type from value field. 6. Click the Color Scheme dropdown arrow and click a color scheme. 7. Click Add All Values. This adds all unique values to the list. Alternatively, click the Add Values button to choose which unique values to display. 8. Since BLK value represents no building, set blank color for BLK value and set same color for the other values. 9. You can group other types into one type. Select other types and right click. Choose Group Values. 9

11 10. If you want to have more descriptive labels, click a label in the Label column and type a new one, e.g. buildings. 11. Click OK. 12. Add the other layers: coastline.shp, bus_stop.shp and set symbols for those layers. 10

12 B. Label your data You will learn how to label layers with information from attribute tables. You can also add additional information by typing text directly on your map. It is useful to label building name, road name etc when producing map. 1. Select wanchai_road layer. 2. Right click properties click Labels Tab. 3. Tick the option Label Features in this layer. Select Label Field is STREET_ENG. And you can set the font size and color of labels by clicking Symbol button. Press OK. 4. Therefore, the road layer is labeled with English road name. C. Display the attributes of a particular feature on a view The Identify tool lets you display the attributes of features on a view by clicking on them with the mouse. Choose the Identify tool and click on any feature on the map to display its attributes. Click the Layers dropdown arrow in the dialog box to specific which layers you want to identify. Try to use the identify Tool until you feel familiar with it. D. Select features with the mouse The Select Feature tool lets you select features with the mouse by pointing at them or by dragging a selection box over them. Features that fall partly or wholly inside the box you define will be selected. Features will be selected from all of layers (default). To specific which layer(s) to be selected, click Selection on the main menu and click Set Selectable Layers. 11

13 You can also select features in attribute table. 1. Select the layer. 2. Right click Open Attribute Table button. The attribute table is displayed and the records for the features you selected are highlighted. 3. To display the highlighted records only, click Selected button at the button of table. 4. You can deselect the selected features in the layer by clicking Selection menu the Clear Selected Features button. Try to use Select Feature tool to select some features, show selected records and clear selection until you feel familiar with these tools. E. Select features with graphics Using the Drawing tool palette you can draw a circle, rectangle or irregular graphic to select features. If you can t find the draw tool bar, go to View menu Toolbar Tick Draw. 1. Click Polygon button from draw toolbar and draw the polygon on the map. 2. To specific which layer(s) to be selected, click Selection on the main menu and click Set Selectable Layers. For example, you make wanchai_road is selectable only. 3. Click Selection menu Select by Graphics. 12

14 F. Select features by querying attribute table Build a query with the attribute values. when you want to select features according to their 1. Suppose you are going to find out all buildings in the building layer whose area is larger than 500 square metres. Make the building them active. 2. Click on the Select menu Select By Attributes. 3. Select building layer and specify you conditions as shown in the following figure. 4. Click the Apply button. 5. If there are any features satisfying the conditions, they will be selected and highlighted in yellow in the view window. Try using this method to find features from your layers and record your queries (no less than 3) in the following table. Query Query conditions in Query builder Number of selected features Select buildings which are not BLK type and area > 500 Select the name of Wan Chai roads include this word QUEEN Select road with name starting with the letters R to Z G. Find features by spatial query You will learn how to do spatial query using the tool to make queries of spatial relationship like within distance of and completely within (i.e. inside). 1. Suppose you want to find out bus stop which are within the buildings, i.e those stops may has problem. 2. Select building layer Properties Definition Query Query Builder. Select type is not equal to BLK. Therefore, only type is not equal to BLK will be displayed. Since blank polygons are also in the building layer, if we don t exclude those polygons, the software will query the bus_stops and blank polygons and therefore all bus stops will be selected. 13

15 3. Go to Select menu Select by Location. 4. Select bus_stop. 5. Select Interest first combo box and select layer which overlay with building layer. 6. Click Apply. 14

16 Here, you are required to use at least two more spatial relations, intersect and complete contain. You are encouraged to try all spatial relationships available in the tool. Record you spatial queries (no less than 4) in the following table. (a) Name of layers(s) to select features from (the first dropdown box) The shape type of (a) (e.g. line, point or polygon) the spatial relation (b) Name of layer to select by The shape type of (b) 15

17 Exercise 3 - Editing data In this exercise, you will learn editing skills for spatial data. You shall create one line shapefile and one polygon shapefile in ArcCatalog to practise the following edit functions. Preparation - Creating a new shapefile 1. Select a folder or folder connection in the Catalog tree. 2. Click the File menu, point to New, and click Shapefile. 3. Click in the Name text box and type a name for the new shapefile. 4. Click the Feature Type drop-down arrow and click the type of geometry the shapefile will contain. 5. Click OK. The new shapefile appears in the folder's contents. A. Start an editing session 1. Add the shapefile you want to edit in ArcMap by clicking the Add Data button. If the shapefile is already added, skip this step. 2. Click Editor and click Start Editing. If you can t find Editor toolbar, click View Toolbars Editor. 3. Click Create New Feature in the Task dropdown arrow. 4. Click the Target layer you want to edit. 5. Click the tool palette dropdown arrow and click the Sketch tool. B. Set the snapping environment When you edit the lines, you may not sure whether the line is snapped and therefore it may affect the data accuracy. Setting the snapping environment can help snap the lines automatically. 1. Go to Editor Start editing. 2. Go to Editor Snapping. 3. In the Snapping Environment dialog, choose which layer you want to snap and also you want to snap to vertex, edge and end. 4. If you want to set snapping tolerance, go to Editor options General tab. 16

18 C. Skills of working with mouse Before you can successfully draw any features, skills listed below are basic for you to do edit. Using the mouse, Single click on left button add a vertex Double click on left button finish digitizing one feature Single click on right button view popup menu D. Digitize features Switch the Target shapefile in order to digitize different kind of features. 1. Position the cursor at the desired feature on the digital image and click left button of the mouse. 2. Continue pressing left button of the mouse to digitize several vertices for the feature. 3. Double left click to end digitizing the feature. 4. Right click to see the popup menu. 5. From the popup menu, you can choose to insert vertex, delete vertex or delete sketch. Above are only basic procedures to create and edit features. There are many functions help to split, cut, mirror and reshape etc features. For more information about editing, please read the help provided in ArcMap. Choose Editing in ArcMap from the contents. Please digitise 10 records each in both line and polygon files, with at least 1 new attribute to be created inside these files. E. Stop editing and save you work When you finish digitizing features, click Editor and click Stop Editing. It is wise to save your work (Save Edits) from time to time during the process digitizing/drawing. 17

19 F. Calculate Value When editing the attribute table, you can use Field Calculator to calculate the value of the field. For example, you can calculate length and area. 1. Open the attribute table. 2. Choose Start Editing from the Editor toolbar. 3. Add a numeric field to the table e.g length, click the name of the field to select it. 4. Click the length column and right click and choose the Calculate button to display the Field Calculator dialog. 5. In dialog, click on the Length field name so that it looks pushed down. Then, right click the function Calculate Values. The following window prompts. Check the Advanced box. Type the following VBA script inside that box. Dim length as double Dim pcurve as ICurve Set pcurve = [Shape] Length = pcurve.length Then also type pcurve.length in the Length box, and then click OK. 6. Think about how to get the area, perimeter, x or y coordinates using VBA Script code. Remark: For more information about making field calculations, please go to ArcGIS Desktop help and search making field calculations about the VBA script details. 18

20 Exercise 4 - Plotting your map After having done analysis, you have to plot your result in previous exercise in paper map. In this section, you learn to design and produce quality map and plot it out in A3 size. A. Create a layout 1. At the left lower corner, switch to Layout View. 2. In the Layout toolbar, you can change the template by using select template button. 3. Select the template you want. 19

21 B. Control scale 1. Click View Data Frame Properties. 2. Set Map and Display units to Meters. 3. Select Data Frame Tab, you can choose Fix Scale, e.g. 1:5000. C. Add elements on the map 1. Go to Insert menu, you can add new components to a layout such as scale bar, north arrow frame, text, image and chart. 2. You can also use draw toolbar to add graphics such as neatlines, boxes, circles and arrows anywhere on your layout. D. Make grid line 1. Click View Data Frame Properties. 2. Select Grids Tab. 3. Click New Grid and select Measure Grid. Click Next. 4. Select Grid and labels. Type in the interval is 500. You can change symbol style by clicking Style button. Click Next. 20

22 5. You can change the style for border and the font size. 6. Tick the options in Measured Grid Border and Neatline. Click Finish. 21

23 Exercise 5 - Making 3D TIN model and terrain analysis For this final exercise, you will learn to TIN model by using contour data. Also, you will perform some terrain analysis based on the TIN model. To perform this exercise using the Coverage folder, 3D analyst extension is required. A. Create TIN model 1. Go to View Toolbars 3D Analyst. 2. Also, go to Tool menu Extensions Tick 3D Analyst Option. Otherwise, the function in 3D Analyst toolbar will be enabled. 3. In ArcMap, add Contour layer by Add Data button and select one part of contour. 4. In 3D Analyst toolbar, go to Create/Modify TIN Create TIN from features. 5. In the dialog, tick Contour layer, select you Cont_ht from Height source and input as hard or soft breaklines. Define the output file path and name. Then press OK. 22

24 B. 3D Visualization With TIN model, you can have 3D view of terrain. Go to All Programs ArcGIS ArcScene. All the tin layer in ArcScene and therefore you can visual 3D view of the terrain model. C. Analysis slope aspect with TIN model One of application for TIN model is to analysis slope aspect. Slope aspect is useful for engineering project to indicate the steepness of slope, especially for those slopes near roads. 1. In ArcMap or ArcScene, click the 3D Analyst menu on the toolbar, point to Surface Analysis, and click Slope. 2. Select the surface from which you want to derive a raster of slope values. 3. Click Degree or Percent. 4. Type a z-factor. This is calculated automatically if the input has a defined spatial reference that includes z unit information. 23

25 5. Type an output cell size. 6. Type the name of the output raster. 7. Click OK. 24

26 Submission Criteria 1. Tables in Section F and G of Exercise One line and polygon shapefiles after performing editing functions in Exercise 3. After editing your shapefiles inside ArcMap, you are necessary to select and copy your shapefiles. A group of 5 or 6 relevant files with the same file name (e.g. bus_stop, coast) with 5 or 6 different extensions. Please keep save all relevant files for submission. 3. The A3 paper map in digital format saved as student ID. In order to export your map in jpeg or pdf format, goto File Export Map. Save your map as either jpeg or pdf format. 4. The printed screen images for the result of section A, B and C in exercise 5. 25