Project 2 CIVL 3161 Advanced Editing

Transcription

1 Project 2 CIVL 3161 Advanced Editing Introduction This project will involve more advanced editing/manipulation of data within ArcGIS. You will use the map that you create in this project as a starting point for Project 3. The project will cover advanced editing using the Selection tools and converting exported tables to displayed x-y data. Project Data Description For this project, a folder is provided in Ecourseware containing a shapefile (called SRTS_Annieupdate) with locations of schools within Shelby County. This file contains demographic information for each school, as well. Project Requirements Using the provided schools data, you will create a map that shows the top ten elementary schools that have the greatest potential percentage of walkers. As you have learned this semester, walk percentages are typically highest for schools with the greatest number of low-income students. Thus, you will select the ten schools with the highest potential number of walkers using the number of students at each school that are considered economically disadvantaged. This item is called EcDNum in the schools shapefile. The finished map should include a title, formatted legend, scale, and north arrow. Procedure 1. Download the schools shapefile from Ecourseware, save it to your computer, and add the file to your ArcMap project using the button. 2. Edit the Layer Properties for the shapefile by double-clicking on the name of the layer in the Table of Contents. Under the General tab, change the name of the layer to West TN Schools (or another descriptive name for the data). See Figure 1 for a screen shot of the Layer Properties window. 3. Click on the Symbology tab, select Quantities, and Graduated Symbols. You can now specify the field that you would like to use to scale the symbols. Select EcDNum from the Value drop-down menu. Change the range of data included in each category to equal intervals. Click on the values under the Range heading in order to do this, and type in a new ending value for each range. It will automatically determine the starting value of the next class interval based on the ending value of the previous class. You can change the type of symbol used by clicking on the button below Template. See Figure 2 for details.

2 Figure 1. Layer Properties - General Figure 2. Layer Properties - Symbology

3 4. Add the county boundaries file (download from to provide geographical orientation for the schools. Your Data View window should look similar Figure 3 below. Figure 3. Data View 5. Next, you will learn to create selections that can be exported from a dataset to create a new layer. Click on the Selection menu, and choose Select by Attributes. Make sure the Layer selected is your schools shapefile, and create a query to select just Memphis City Elementary Schools. To create a query, double click on an attribute name, use the appropriate calculation button, and select the attribute value that you wish to select. Choose Get Unique Values to select directly from the list of available attribute values for each field. You can include multiple levels of selection by including the word and to connect additional query statements. Click Apply and Ok when you are finished. See Figures 4 and 5 for details. 6. Right click on the name of your schools shapefile in the Table of Contents. Open the attribute table. In the lower left corner of the attribute table window, click on the button to display only the selected records. You can then sort the records by the EcDNum column in descending order to identify your top 10 schools. Highlight the remaining schools in the list (click on the first one below your 10 th school, hold down Shift and then select the last record in the list). Choose Unselect Highlighted from the buttons across the

4 top of the table window to remove these additional schools from your list. See Figures 6 and 7 for details. Figure 4. Selection Menu Figure 5. Select by Attributes

5 Figure 6. Show Selected Records Figure 7. Sort Descending 7. Right click on the name of your schools shapefile in the Table of Contents again, and select Export. Export the selected records to the default location.

6 Click yes when you are prompted to indicate whether or not you would like to add the data to your project. If your version of ArcMap allows you to import as a layer, then your data will appear as a point layer. Otherwise, you will see a table appear in the Table of Contents. To associate this table to its spatial location, simply right click on the name of the table, select Add X Y Data and select the appropriate fields containing your x and y coordinates. 8. Once you have the shapefile containing just the top 10 elementary schools, you can clear the selected features in your data view by returning to the Selection menu and clicking on Clear Selected Features. Change the symbol of your new layer of schools to something appropriate, and change the name of the layer in the Table of Contents. Your data view should now look similar to Figure 8. You now have a separate layer for your selected schools so that you can do additional analysis on these in Project 3. Figure 8. Top 10 Selected Schools *Remember, to make your map more visually pleasing and informative, edit the names of the layers in the table of contents to make them something appropriately descriptive, and add a legend, scale, north arrow, title, borders, etc. from the Insert menu on the Layout View. Zoom in to the extent that you would like to see displayed in your map in the Data View before you switch to the Layout View. To display your attribute table on your map layout, double click on the layer, choose the Fields tab, and select the fields you would like to display on the table. You can also change the field heading by changing the Alias name. Once you have the field display options selected, open the attribute table for the layer and from the Table

7 Options drop-down menu, select Add Table to Layout as shown in Figure 9. The finished product should look similar to Figure 10 Figure 9. Add Table to Layout

8 Figure 10. Final Map

9 Grading Rubric Requirement Formatting Requirements Figure has title, legend, scale, north arrow Technical Requirements Elementary schools are properly selected such that the top 10 Memphis City District Elementary schools by number of economically disadvantaged students are identified Map is clear and easy to read- appropriate symbology is used to convey relative number of students that are economically disadvantaged at each school included in the map Table displaying ranked list of schools and number of economically disadvantaged students is included in the figure One additional refinement beyond that described in the project procedure is included to improve clarity of the map and to demonstrate mastery of the skill (for instance, rather than including all schools in the scaled symbology, you might only show elementary schools, or only elementary schools within Memphis City Schools, to improve visualization and decrease confusion of displaying middle and high schools in the scaled display, etc.) Participation Requirement Participation in class training session required for Project 3 Point Value 20 pts. 20 pts. 10 pts. 10 pts. 20 pts. 20 pts.