GEOG4017 Geographical Information Systems Lab 3 Data Collection and Integration (I)

Transcription

1 DEPARTMENT OF GEOGRAPHY HONG KONG BAPTIST UNIVERSITY Prof. Q. Zhou GEOG4017 Geographical Information Systems Lab 3 Data Collection and Integration (I) Objectives Before we can use GIS for any analysis and decision support, the geographical data in GIS must be properly prepared. In this exercise, students are asked to produce a map which shows the distribution of health services facilities in Hong Kong Island, and further package it to be shared in various ways. After finishing the lab works, students should learn to: Create geographical data subset by extracting and aggregating features in feature class; Create feature class using XY coordinates; Display geographical data in different coordinate system using projection on fly; Share the map in ArcGIS for Desktop as Map Package and Service; Guidelines Preparation 1. Logon to workstation using your GISLAB account. Start ArcMap with a Blank Map. Edit the document properties (select File > Map Document Properties ). Change the Title to be Public Health Services in Hong Kong Island, and the Author to be (your name). 2. Open the Catalog window (by selecting Windows > Catalog) if you have not done so. Expand the Folder Connections, you should find there is one connection which connects to your J Drive (J:). Add another connection to your K Drive (K:) by clicking the Connect to Folder window, and select (K:) from Computer. button in Catalog Expand both J: and K: under Folder Connections and you should be able to find the \geog4017 subfolders in both drives.

2 3. Copy entire K:\geog4017\lab3 folder to J:\geog4017, you can do it in either ways listed below: drag the \lab3 folder in K:\geog4017 and drop it to J:\geog4017, or; right click the K:\geog4017\lab3 and select Copy, then right click the J:\geog4017 and select Paste; The folder contains three shapefile and one text file (the csv file was created using Microsoft Excel): hk_districtcouncils.shp location and information of District Councils districts for whole Hong Kong (same as what you got in lab 1); hk_hospitals_selected.shp location and information of selected hospitals for whole Hong Kong (same as what you got in lab 1); hki_new_hospital.shp location and information of a new hospital located in Hong Kong Island (which is not included in hk_hospitals_selected.shp); hki_clinics_coord.csv names and coordinates (in Universal Transverse Mercator UTM) of clinics in Hong Kong Island which are managed by Hospital Authority; 4. Save your map document (File > Save) as lab3.mxd and place it in J:\geog4017\lab3. Create subset of geographical data 5. Create a copy for hk_districtcouncils.shp, which will be used to store the boundary of Hong Kong Island. In the Catalog window, right click the J:\geog4017\lab3\hk_districtcouncils.shp and select Copy, then right click the J:\geog4017\lab3 and select Paste. A new shapefile hk_districtcouncilcopy.shp will be created. Rename it to hki_extent.shp (right click > Rename). The original hk_districtcouncils.shp is useless here. You may delete it by right clicking it then select Delete. 6. Add all the files in J:\geog4017\lab3 (listed in step 3) into the data frame as layers and table (File > Add Data > Add Data ). You may also add data by dragging files from Catalog window and dropping them in the view. 7. Our study area is limited to Hong Kong Island (that covers Central and Western, Wan Chai, Eastern, and Southern districts). We need to create a feature class which shows the extent of Hong Kong Island only from hki_extent.shp. Activate the Editor toolbar (Customize > Toolbars > Editor), press [Editor] button and select Start Editing to start and editing session. In the Start Editing dialog box, select layer hki_extent and click [OK] to continue.

3 Open the attribute table of hki_extent layer (right click > Open Attribute Table), select the four District Councils which belong to Hong Kong island (Central and Western, Wan Chai, Eastern, Southern) (hold the [Ctrl] key in your keyboard, then click the leftmost cell of each record). Then press [Table Options] button and select Switch Selection. Question: What happened when you select Switch Selection? Delete the selected records by clicking the [Delete Selected] button (or by right clicking the leftmost column and select Delete Selected). Then switch to Editor toolbar, press [Editor] > Stop Editing, select [YES] to save your edit and stop editing. 8. We may need to use different geoprocessing tools to manipulate our geographical data since now. All the geoprocessing tools are placed in the ArcToolbox. The ArcToolbox window is the central place where you find, manage, and execute geoprocessing tools. Tools can also be managed and executed from ArcCatalog. The ArcToolbox window contains toolboxes, which in turn contain tools and toolsets (a toolset is just an organizational device, like a system folder). Tools must be contained in a toolbox they cannot exist outside a toolbox.

4 Launch ArcToolbox (Geoprocessing > ArcToolbox). From the Data Management Tools toolbox, Generalization toolset, open the Dissolve tool (by double clicking it or by right clicking it and select Open ). In the Dissolve dialog box: Set the Input Features to be hki_extent Name the Output Feature Class as hkisland.shp and place it in J:\geog4017\lab3 folder Leave other fields as default and then press [OK] to run the tool. You may get the description of the tool and fields by pressing the [Show Help >>] button. Once the dissolve completes, the shapefile hkisland.shp will be added into the data frame as a layer automatically. Check the extent as well as the attribute table of this layer.

5 Question: What did dissolve perform here? You may close or rearrange toolbar, table or window as you wish. Keep workspace tidy and clean as to increase your efficiency. 9. We will use the newly created hkisland.shp to create a subset for hospital in Hong Kong Island based on location. We will use the Clip tool in this case. Launch ArcToolbox (Geoprocessing > ArcToolbox if you have already closed it). From the Analysis Tools toolbox, Extract toolset, open the Clip tool. You may also launch the Clip tool by selecting Geoprocessing > Clip. In the Clip dialog box: Set the Input Features to be hk_hospitals_select Set the Clip Features to be hkisland Name the Output Feature Class to be hki_hospitals_partial.shp (place it in J:\geog4017\lab3) Leave other fields as default and then press [OK] to run the tool. The shapefile hki_hospitals_partial.shp will be added into data frame as a layer after the Clip is completed. Check the extent as well as the attribute table of this layer. Question: In our this case, can you suggest another way to create a subset of hospitals apart from using any tool in ArcToolbox? (hint: check the attribute table of hk_hospitals_selected layer again.) Aggregate geographical data 10. Unfortunately our original hk_hospitals_selected.shp is not updated. A hospital has been established in Hong Kong Island recently and it is not included in hk_hospitals_selected.shp. Its information is placed in another shapefile hki_new_hospital.shp. We need to create a new feature class, which combines the data of hki_hospitals_partial.shp and

6 hki_new_hospital.shp. We will use the Merge tool to do this. Launch ArcToolbox (Geoprocessing > ArcToolbox if you have already closed it). From the Data Management Tools toolbox, General toolset, open the Merge tool. In the Merge dialog box: Set the Input Datasets to be hki_hospitals_partial and hki_new_hospital Name the Output Dataset to be hki_hospitals_updated.shp (place it in J:\geog4017\lab3) Leave other fields as default and then press [OK] to run the tool. The shapefile hki_hospitals_updated.shp will be added into data frame as a layer after the Merge is completed. Check the extent as well as the attribute table of this layer. Questions: Can you find the new hospital in hki_hospitals_updated? What is its name? You may find a similar tool Append in ArcToolbox (in Data Management Tools toolbox, General toolset). Can you briefly state the difference between Merge and Append? Does Append suitable in our previous operation? (you may try to perform Append to check the result). Create features using XY Table 11. Apart from hospitals, we also want to create a feature class that contains the location and information of clinics in Hong Kong Island. There is no pre made digital map available. Nevertheless we were able to find the list from Hospital Authority, and the coordinates of the clinics may be collected (in UTM Universal Transverse Mercator) may be collected by using Google Earth. Universal Transverse Mercator coordinates can be shown in Google Earth The names and coordinates of the clinics are stored in the hki_clinics_coord.csv file, which you

7 should already added it into the data frame as a table. Have a look on it by right clicking it in the Table of Contents and select Open. Question: In computing, a comma separated values (CSV) file stores tabular data (numbers and text) in plain text. Each line of the file is a data record. Each record consists of one or more fields, separated by commas. CSV is a common data exchange format that is widely supported by consumer, business, and scientific applications. Which field(s) store(s) the coordinates of clinics in this table? Can you guess their meaning? 12. We may use the information in this csv file to create the required feature class. Right click it again and select Display XY Data this time. In the Display XY Data dialog box, set UTM_E as X Field, and UTM_N as Y Field, leave others as default and press [OK]. A warning will be prompted, study carefully and press [OK] to create the layer. 13. A new layer hki_clinics_coord.csv Events is created and it should appears in the Table of Contents. However, you should find that NO clinic is shown in our map. Check the coordinates of our current map extent (at the bottom right corner of the view). Then zoom to the extent of hki_clinics_coord.csv Events by right clicking it and select Zoom To Layer.

8 Question: Can you explain what is happening briefly? You should check the coordinate system of the current data frame by selecting View > Data Frame Properties then check the [Coordinate System] tab. Return to original map extent (right click the hkisland layer and select Zoon To Layer), and remove the newly created hki_clinics_coord.csv Events layer (right click > Remove). We need to recreate this layer again. 14. Repeat step 11 (right click hki_clinics_coord.csv > Display XY Data ). Remember to set the proper X Field and Y Field first. But this time we also need to set the Coordinate System of Input Coordinates. Press the [Edit ] button in Display XY Data dialog box.

9 In the Spatial Reference dialog box, choose WGS1984 UTM Zone 50N from Projected Coordinate Systems > UTM > WGS1984 > Northern Hemisphere. Press [OK] to return. In the Display XY Data dialog box, press [OK]. You will face the same warning as that in step 11, press [OK] to create the layer. 15. This time the clinics should be properly displayed. Question: Record the following clinics coordinates in Hong Kong 1980 Grid from your data frame and put your answers in the below table: (you may locate the clinic by manually selecting it in Attribute Table, or by using the Select by Attributes tool (select Selection > Select by Attributes > (type appropriate SQL Statement)). Coordinates of the feature may be obtained at the bottom right corner of the View.) Tung Wah Hospital GOPC Violet Peel General Out patient Clinic Ap Lei Chau General Out patient Clinic Chai Wan General Out patient Clinic Stanley General Out patient Clinic UTM (E) UTM (N) HK1980(E) HK1980(N) ArcMap displays all layers in a data frame in the coordinate system that has been set for that data frame. This process is called projection on the fly. Projection on the fly makes it possible to align data from different coordinate systems in the same data frame. This means that ArcMap displays a dataset stored in coordinate system A as if it were in coordinate system B. The coordinate system of the source data (stored on disk) is not changed.

10 16. We may save this layer as a shapefile by right clicking it and selecting Data > Export Data. In Export Data dialog box: Set Export All features Use the same coordinate system as: the data frame Name the Output feature class to be hki_clinics.shp (place it in J:\geog4017\lab3) Press [OK] to create the shapefile. Questions: Suggest another way to physically recalculate the coordinate of a data into a different projected and/or geographic coordinate system in ArcGIS for Desktop. In case we have a XY table which contains the longitudes and latitudes of different place, when we want to create a feature class using this table, which coordinate system would we use? 17. Remove all layers and table EXCEPT hki_clinics hki_hospitals.updated hkisland If you want to change the display order of the layers, you need to change the list method to be List By Drawing Order (in Table of Contents).

11 Share map as Map Package and Service to ArcGIS Online 18. Select File > Share As > Map Package In Map Package, select Upload package to my ArcGIS Online account and name it HKI health services. (you will be asked to sign in your ArcGIS Online account before proceed.) You need to select Sign in with ENTERPRISE ACCOUNT to sign in your ArcGIS Online account in HKBUGEOG.MAPS.ARCGIS.COM. In Item Description, type Hospitals and Clinics in Hong Kong Island in Summary, and health service; hospital; clinic; Hong Kong in Tags (pay attention that both fields are marked as required). No need to set Additional Files and Sharing at this moment.

12 19. Before we can procced, we should analyze the map package to check if there is any problem. Press the [Analyze] button at the upper right of the dialog box. You should aware that a High Severity error is found, which mention that Map document description is required for packaging. Right click this message and select Add Map Description. In the Map Document Properties dialog box, add GEOG4017 Lab 3 exercise in Description field, press [OK] to close it. Analyze the map package again and see if there is still any error, warning or message. 20. In the Map Package dialog box, press [Share] button. A warning will be prompted which ask you to save your map document. Press [Yes] to continue. A Succeeded message will appear when the map package is uploaded. Press [OK] to close it. 21. Use any browser (Internet Explorer, Chrome, Firefox, Safari, etc) you like, navigate to Sign in using the account information of your ArcGIS Online account. In the organization map site, check Content, you should be the HKI health services has been uploaded as a Map Package. In case you share it, other people may download it as a Map Package file (*.mpk) and open it in their workstations using ArcGIS for Desktop. 22. Return to ArcMap. This time we will share it as a service. Select File > Share As > Service. Select Publish a service in the first screen and press [Next >]. In the next screen, select My Hosted Services (Department of Geography, Hong Kong Baptist University) as connect and name the service hki_health_services. Press [Continue].

13 In the Service Editor dialog box, we do not have any item needs to be set at this moment (Some options have been set because you signed in and created a Map Package before). You may directly press the [Analyze] to check if there is any error. You may find some warnings and messages. They may influence your result but will not prevent you to create the service. Here you may press the [Publish] button to publish it straightly. You may also preview the service before you publish it. 23. Switch to ArcGIS Online in the browser. Refresh the Content page. You should find a feature layer (hosted) and a service definition are added. Open the hki_health_services Feature Layer (hosted) in Map Viewer (click its name then press [Open in Map Viewer] button. Move around and try to display it in different style. Know more about different item types in ArcGIS via the online help: Map Package: witharcmap/creating a map package.htm Feature Layer (Hosted): online/share maps/hostedweb layers.htm Service Definition: service definition files.htm

14 Question: In case you want to create a web app (say, a story map) using the data you prepared in ArcGIS for Desktop, which way should you share your map? 24. Once you finish exploring the uploaded services in ArcGIS Online, you may sign out from it (select Your Name > Sign Out) and close the browser. Moreover, return to ArcMap, select File > Sign Out (your id) to sign out ArcGIS Online. Save your map document again (File > Save) then quit ArcMap (File > Exit). Turn off your workstation before you leave.