GIS BASICS. GIS Foundations 2. Kevin Kuhn & Jennifer Smith WV GIS Technical Center (

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1 GIS BASICS GIS Foundations 2 Kevin Kuhn & Jennifer Smith WV GIS Technical Center (

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3 GIS BASICS Course Overview This course is designed to provide an overview of the basic building components for an effective and useful GIS. It builds upon previously existing knowledge of how ArcGIS works and the different components of GIS. The course focuses on best practices for building a functioning GIS, beginning with databases and tables in Module 1. The course then covers effective querying and selection processes (Module 2), basic analysis tools (Module 3), and the very basics of editing (Module 4). The course is composed of four modules, each containing lecture, demonstrations, and hands on activities. Compared to other courses, portions of this course focus more on hands on activities training in ArcGIS. Lecture Lecture is designed to be brief and introduce key concepts, focused on the correct application of geographic information systems and processes. Demonstrations Live demonstrates are used to reinforce the concepts taught in the lecture portion of each module. Demonstrations may be completed as part of the lecture or as a separate segment. Some demonstrations may be conducted as a hands on activity with the instructor to preview tasks which will be completed in the activity portion of the course. Hands-On Activities This workbook is designed to give you practical hands on experience using and applying GIS to everyday life, workflows, and tasks. They also build upon and demonstrate key concepts covered in the lecture portion of this course. At the end of the hands on manual you should be able to create and edit data, search data, export a selection of data, import data to a geodatabase, and extract data based upon specific sets of criteria. 2 P a g e

4 Table of Contents Course Overview... 2 Lecture... 2 Demonstrations... 2 Module 1: Tables and Attribute Features... 4 Activity 1.1: Importing Tables... 4 Activity 1.2 Databases and Tables a valuable and common data source... 7 Activity 1.3: Matching your Data Activity 1.4: Adding Fields and the Field Calculator Activity 1.5: Calculating Geometry (optional exercise) Module 2: Selecting and Querying Data Activity 2.1: Building a Definition Query Activity 2.2: Selecting by Attribute Activity 2.3: Selecting by Location Activity 2.4: Complex Definition Queries (Optional Activity) Optional on your own exercise: add a related table to find out who owns this parcel Activity 2.5: Summarize a Column and get Statistics (Optional Activity) Module 3: Editing Basics Activity 3.1: The Editing Toolbar Activity 3.2: Creating New Features Optional Activity: If you have extra time, collect the rest of the parcels along Lucas Drive Activity 3.3: Editing Tools Search Features in ArcGIS Activity 3.4: Completing the Dataset (If Time Permits) Module 4: Basic Analysis Tools and Features Activity 4.1: Set-up Project Activity4.2: Find empty lots Activity 4.3: Clip, Buffer, Intersect foundations for analysis and data management Activity 4.4: Final Analysis Optional Exercise: Map it! Page 3

5 Module 1: Tables and Attribute Features Activity 1.1: Importing Tables Databases (or tables) often come in a variety of formats but contain a wealth of data. Within a GIS, there is a large focus on the data containing locational information, preferably latitude and longitude coordinates. Note: There are several methods and tools to Import tables into a GIS is relatively simple. To convert those tables to a geographic dataset can, however, be tricky. import it into a geodatabase, compatible with ArcGIS, first. Importing a table first can help point out problems and compatibility with the table that are un-related to the coordinate data and prepare for a smoother feature class or shapefile creation. Open Arc Catalog. Navigate to the C:\student folder. o Make a folder connection if necessary o File>Connect to Folder>C:>student Right click on the Newspace_Development_Area.gdb Click Import from the list. Import > Table (single) 4 P a g e

6 Input Rows = parcels_owners.xlsx o Sheet 1$ o Click the plus sign next to parcel_owners in your Catalog Tree o Drag Sheet1$ over to your Table to Table Tool window and drop it in the Input Rows window. Output Table = Newspc_own Click OK. Note: This import may not work! (Please see below!) When Arc is done processing the tool, a small box will appear in the lower right hand corner of your screen to let you know if the table to table conversion worked. A red circle with an x in the middle means the conversion failed. What are the results of your import? Sometimes Arc has a hard time communicating with newer software versions. Close Arc Catalog** IF YOUR IMPORT FAILS, TRY THE METHOD ON THE NEXT PAGE. Page 5

7 **Note: ArcMap and ArcCatalog generate lock files when you are using files in one of their software programs. This sometimes prohibits you from opening or viewing the file in another application or even continuing to use it in Arc. Be sure that when you are changing a file, or using a file in two programs, that you close the program before working in Arc again. Also, it sometimes takes a few minutes for Arc to realize that you closed the other application. Open the parcel_owners.xlsx spreadsheet in Microsoft Excel. Go to File > Save As Navigate to your C:\student folder Leave the file name the same, but change the file format to workbook (.xls) (instead of.xlsx) or compatibility format. Close Microsoft Excel. Reopen Arc Catalog. Right click on Newspace_Development_Area.gdb again. Import > Table (single) Be sure your input rows are coming from the newly saved (.xls) spreadsheet instead of the old one. o Choose Sheet1$ from the.xls file. Output table = Newspc_own_b Also Note that even though Arc did not import the table correctly the first time, therefore not generating a new file, naming the file the same can cause hiccups. So try to give failed import, or any failed tool output, file names an additional identifier such as _b or _2 to avoid further complications. Click OK. Close ArcCatalog. 6 P a g e

8 Activity 1.2 Databases and Tables a valuable and common data source Open the ArcMap Project GF2_M1_Activity1.2 Right click on the Newspace_buildings layer and choose Open Attribute Table. Look at the fields and the data populating the table. You can probably deduce from the content of the cells what some of the fields mean. Can you tell what the data types are for all fields? Right click on the Newspace_buidlings layer > Properties. Choose the Fields Tab. Each of the fields and it s details is listed in this tab. You can change the order of the fields and which fields are visible in this tab as well. In addition to the text data type, what are the other data types represented in this dataset? Click Cancel or close the Layer Properties window. Storing information in a database has many benefits such as sorting, querying, and associating applications (joins and relates). Open the attribute table for the Newspace_footprints. Right click on the layer > Open attribute table Select the Shape Area Field. Hover over Shape Area > left click once. It will turn cyan or highlight in blue when it is selected. Page 7

9 Right click and choose Sort Ascending. The smallest structure should be at the top of the list. Right click again and this time Sort Descending. Double clicking on the field will also sort ascending, double click again and it sorts descending. Now the largest structure is on top. You also have the ability to pin (dock), minimize, split, and hide your table. Click in the Table window header and start to drag your table. o Several blue arrows should appear. Dragging your table over one of these arrows until it turns a darker shade of blue, will enable you to dock your table to that location. Drag the table to the bottom blue arrow and release the left click button. Click the Globe to zoom to full extent. Clear selected features by going to Selection in the main toolbar. Choose Clear Selected Features. Click the little pin in the upper right hand corner of the table window auto hide. The table is now in the lower left hand corner of your ArcMap window. 8 P a g e

10 Click on the Table. Scroll towards the top of ArcMap and click anywhere in the data frame. This time, click on the table, click the pin to pin it in place. One of the features lost with the shift from Arc 9.3 to 10.0 and beyond is the ability to open two tables in two separate windows. Right click on Newspace_buildings Open Attribute Table The second table opens as a tab in your existing, pinned, table. If you wanted to compare the tables you ll have to split the window. Close the attribute tables by clicking the x in the upper right hand corner. Go to ArcCatalog that is pinned to the right side of your ArcMap window Or ADD DATA. Add the Newspc_own table you imported earlier to your project. Right click on the Newspc_own_b table you just added. Select Open. Right click on the Newspc_parcels layer > Open Attribute Table. To view the tables side by side: o o o Left click on the tab Newspc_parcels Drag the tab to right until your blue arrows appear. Select the down arrow by hovering your mouse over it it should turn dark blue. Page 9

11 o Release the left mouse button. To move the table to view them side by side, grab the Newspc_parcels table in the table window header and drag it to a blue arrow (The left or right arrow). Note: You loaded the table Newspc_own table into ArcMap even though it has no spatial information. You will not be able to see the table if you switch your Table of Contents from Source View to Data View. 10 P a g e

12 Based upon the two tables you have open, what are some common identifying fields we could use to match the parcel owner to the parcel location? Close the attribute tables. Save your MXD. Activity 1.3: Matching your Data If you closed ArcMap at the end of the last activity, re-open GF2_M1_Activity1.2.mxd. From ArcCatalog, Add the following tables to your project: o C:\student\Data\NewSpace_Development_Area.gdb Site_type Type2_code Right click on and Open site_type. The code field in this table corresponds to the site_type field in the Newspace_buildings attribute table. Page 11

13 Right click on the Newspace_buildings layer > Joins and Relates > Join. Use the pull down menu to view your join options. Choose Join Attributes from a table The Field that the join will be based on is: SITE_TYPE Table to join to this layer: site_type Choose the field in the table to base the join on: CODE Under Join Options, choose to keep all records. Click Validate Join. (The validation report will tell you if all of your features have a match). Once your join is validated, click OK. 12 P a g e

14 Right click on Newspace_buildings > Open Attribute table In the attribute table, scroll to the right of your table. You will now see the descriptions of the codes. Choose a feature by clicking on one of the building footprints in the BonVista sub-division. o With the building selected, you should have a corresponding highlight in your table of contents. What additional information is now available after the join? (List a few examples) When executing a join, it is imperative that the join is based on fields with the same data type. Even if both fields contain a number, such as an ID number, that they be the same data type. One cannot be an integer and the other a text. Be sure to join off of fields that are identical in data type. Similar to a join, you can also relate tables. Joining tables requires a 1-1 or a 1 to many relationship, while relating tables can have many to many relationships. However, they do not show up in the attribute table because of their complexity. Close the attribute table. Right click on the Newspc_parcels layer o o Click Joins and Relates Choose Relate 1. Choose the field the Relate will be based on: TAX_ID 2. Choose the table or layer: Newspc_own_b 3. Choose the field in the related table: Tax_ID 4. Choose a name for the relate: Owners1 Click OK. Go to the Bookmark Cedarwood for the Cedarwood Subdivision. Page 13

15 Click on the identify tool o Remember to set your Identify Target! Click on the parcel. In the Identify Results window, click the plus sign associated with the related table. Using the Identify Tool, who owns the parcel with TaxID 26789? Who owns the parcel the apartment buildings are on (Tax ID 26703)? Who owns the house on Tax ID Right click on the table Newspc_own_b in the Table of Contents and open it. o You may need to switch from Drawing Order to Source view to see the table in the TOC. Notice that Charles and Jane Bingly are listed separately in the document, and that Fitzwilliam Darcy owns many properties. While Mr. Darcy owns many properties, the Bingly and Musgrove properties have many owners. Activity 1.4: Adding Fields and the Field Calculator ArcMap creates an environment where you can view and access many data sources and often new information is generated through the use of GIS. Sometimes that information is not yet stored in one location. In this exercise, you will create a new field, and calculate it s value based upon a joined in table. Be sure your Table of Contents is in List by Source. Right click on the type2_code table > Properties 14 P a g e

16 Go to the Fields Tab. Select the Sum_Desc. What is the Data Type, Name, and Null value of the SumDesc Field? Click OK when you have collected the information. Right click on Newspace_footprints > Open attribute table. In the upper left hand corner of the attribute table, click the Table Options Icon. From the drop down list, choose Add Field. Name the new field Descript. Alias: Description Use the information you collected about the data type and length to fill in your Add Field values. Leave Default Value blank. Click OK. Right click on Newspace_footprints again. Joins and Relates > Join Page 15

17 In Join Data: o Join attributes from a table o The join will be based on Type2 o The table to join to this layer is type2_code o The field in the table to base the join on is: Type2_Code o Keep All Records o Validate Join Despite the caution symbol, click OK to join the table anyways. Open the attribute table for Newspace_footprints. Explore the results of your join. After examining the attribute table, why did your validation of the join give you an error? Which object did not join? Why not? Select the newly added field, Description, and right click on the header. o The column should turn cyan/bluegreen when it is selected. Choose Field Calculator. Click Yes and accept the conditions of calculating outside of an editing session. While the work you do outside of an editing session can t be undone, it can be recalculated later to fix any errors that may occur. Change your parser to Python. 16 P a g e

18 ESRI has switched its main programming language to Python from Visual Basic, so going forward we will use Python as much as possible. Scroll through the list of fields in the column. Notice that the beginning of each field identifies the source of the field (the original database or the table). The Field Calculator allows us to build a code (using Python). The components are already built to make it more user friendly. In this instance, we re just assigning another value rather than using a complex calculation. However, you can see that complex calculations can be done using this interface. Note: If you change the Type of data in the middle of the window, the possible Functions also change. In the Fields window, scroll to the bottom to type2_code.sumdesc Double click on the type2_code.sumdesc to place it in the window. Page 17

19 The Calculation now reads: [type2_code.sumdesc] So the Descript column will have the same values as the SumDesc column from the other table. Click OK. Right click on Newspace_footprints > Joins and Relates > Remove Join > type2_code When you open the attribute table the information from the type2 table is gone however the descriptions remain. 18 P a g e

20 Activity 1.5: Calculating Geometry (optional exercise) Location information is stored within the database such as latitude and longitude or northings and eastings. If you want to generate these coordinates, you can also calculate geometry. Open Newspace_footprints attribute table. Add two new fields o Field 1: Name: LatY Type: Double Field Properties OK o Field 2: Alias: Latitude Name: LongX Type: Double Allow Null Values: YES Default value: Field Properties OK Alias: Longitude Allow Null Values: YES Default value: Page 19

21 Right click on Latitude. Choose Calculate Geometry. Choose Yes to calculate geometry outside of an editing session. Using the pull down menu of Property, choose Y Coordinate of Centroid. o Note: Latitude corresponds to the Y axis, hence LatY Coordinate System: Use coordinate system of the data source Change the Units to Decimal Degrees Click OK. Right click on the Longitude Field > Calculate Geometry>YES Property: X Coordinate of Centroid Use coordinate system of data source Units: Decimal Degrees OK Save your MXD as GF2_M1_Activities_yourname 20 P a g e

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23 Module 2: Selecting and Querying Data The ability to select by location, attributes, and query (ask questions) of your data is one of the strongest analytical capabilities of a GIS. Many institutions and agencies work to convert their data to digital format so they have this ability which leads to the ability to model and analyze complex spatial systems. The scenario: The data used in the course is provided from a planning or community development perspective. The following activities and the rest of the modules for this course will follow this theme as the planning commission for Newspace Community uses GIS to find the ideal/optimal location to build a park. The following activities will help narrow the parcels and spaces which can/should be obtained for park use. Open the GF2_M2_Activities.mxd Activity 2.1: Building a Definition Query Definition queries allow you to specify the parameters of a layer based on an SQL query. You can use definition queries to limit what data is displayed or select specific features. In your Table of Contents, right click on Newspc_parcels Open the attribute table and move it to a different monitor. How many parcels are there? Right click on Newspc_parcels again. Go to Properties > Definition Query Tab Click on the Query Builder button. 22 P a g e

24 This window displays the fields (columns) listed in your attribute table. This window can display the unique values in those fields. This is where you build your query. Newspace Development Authority has no jurisdiction over parcels in District 18. To remove them from view without deleting them from the dataset a definition query is used. In the first window, scroll down to DIST. Double click DIST to place it as the first variable in the query. Now click the NOT EQUAL button <>. With DIST highlighted in blue in the top window, click the Get Unique Values Button. From the list, choose 18. (note: 18 must be in single quotes). Hint: Using the get unique values button helps to reduce typographical errors which can prevent your equation from working. Though there will be instances where you will need to type in the proper Syntax in order to make the query work. Compare your Query Builder to the graphic on the next page. Page 23

25 Click VERIFY. If the equation verifies, then click OK. o If the equation does NOT verify, contact your instructor for additional help. Click OK in your Layer Properties window. Zoom to the layer Newspc_parcels o Hint: to zoom to this specific layer, right click on the layer in the table of contents and choose the option to Zoom to Layer. Some of the adjacent parcels should be missing from your map and attribute table. How many parcels are in your layer after the query has been applied? 24 P a g e

26 What are some of the advantages of using a definition query, rather than simply deleting all of the parcels in District 18? Save your MXD before moving on to the next activity. Leave the attribute table for the parcel dataset open. Activity 2.2: Selecting by Attribute The same type of query builder is used when selecting features by attribute. Go to Selection in the Main Menu. Click on Selection and choose Select by Attributes. In the Layer drop down list, choose the Newsp_parcels layer. Your selection method is Create a new selection. Next you will build a query: LandUse = GS : Scroll through the list and double click LandUse. With LandUse selected in blue, click the Get Unique Values button. Use the = button to set up the query. Page 25

27 Double click GS Green Space (designated) to add it to your equation after the equal sign. Compare your Select By Attributes window to the figure to the right. Verify the equation. Click Apply. Click OK. Right click on Newspc_parcels in the Table of Contents. Selection > Zoom to Selected Features. 26 P a g e

28 Right click on Newspc_parcels > Open Attribute Table In the bottom of the attribute window, the software tells you how many features have a land use classification of Green Space. You can also switch the attribute table to display ONLY the selected records. Click the highlighted rows to Show Selected Records. In addition to creating a new selection, selection options also permit you to: Add to current selection Remove from current selection Select from current selection Go to Table Options in the attribute table for Newspc_parcels. Choose Select by Attributes from the list. Page 27

29 Change your selection method to select from current selection. This time search for parcels that have an area greater than or equal to 7000ft 2 in area. Double click Shape_Area. Use the >= button in the query builder. Then type o Make sure there is a space between the = and the 7. Verify the equation. Apply. Close. How many parcels meet both of these criteria (area greater than 7000m 2 and designated as green space)? If you made a mistake or selected the wrong features you can Clear Selected Features in several ways. Return to the Selection menu > Clear Selected Features. Click the Clear Selected Feature button in your main toolbar. Right Click on the layer > Clear Selected Features o This is particularly useful if you have features selected in multiple layers. This will only clear the features selected in this dataset. 28 P a g e

30 In contrast if you want to select a feature that has accidentally been de-selected, or are manually selecting features use the select feature tool. Activity 2.3: Selecting by Location Selecting by location offers the more geographic approach to choosing parcels. Go to Selection > Select by Location Selection Method: select features from Target Layers: Newspc_parcels o o Check the box next to Newspc_parcels Note: the Target layer refers to the layer you want selected, or want to select from. The source layer is the qualifying geographic location to be selected. Source Layer: Newspace_footprints Spatial Selection method for target layer feature(s): completely contain the source layer feature. Refer to the Figure to the right before clicking Apply. Click Apply. How many parcels have a structure completely contained within them? To find a location for a park, it would be more helpful to know which parcels do NOT have structures. Page 29

31 Open the attribute table for Newspc_parcels if it is not already open. Within the attribute table you can switch selection o This means you will select all of the parcels that DID NOT meet your initial criteria since there is not a does not contain any of the source features options. Click the Switch Selection button. o Alternatively, you can also click the Table Options and choose Switch Selection there. This selection has some problems you will continue to refine the parcel selection. Open the Select by Location Window again. o Selection > Select by Location This time, in the Selection method drop down list choose: remove from the currently selected features. Target layer: Newspc_parcels Change the source layer to Newspace_addresses o This layer represents address points, therefore non-addressed structures such as garages and storage sheds will not be included in our selection. Click Apply How many features meet this criteria? 30 P a g e

32 This seems like a reasonable place to start though there are still some problems. Let s export this data set to its own layer and reduce the amount of data we re working with. Right click on Newspc_parcels From the list choose Data > Export Data You want to export: Selected Features Use the same coordinate system as: this layer s source data Output feature class (new data layer): o o Click on the little yellow folder Navigate to your C:\student\ArcGIS2\Data Name the file empty_parcels The Save As type should be.shp (shapefile). Click OK. Click YES to add the layer to your ArcMap Project. Page 31

33 Turn off your Newspc_parcels layer o Uncheck the box next to the layer in the Table of contents Go to the Cedar Ridge bookmark. o Bookmarks is in the main menu line. Right Click on empty_parcels > Properties > symbology Change the symbology of your parcel layer to have a thick orange outline and no color for the fill. o Leave the Features as Single Symbol o Click on the symbol to edit the appearance. o Fill Color = no color o Outline color = Orange o Outline width = 4.00 o Click OK. Go to the Labels Tab. 32 P a g e

34 Check the box to label features in this layer Method: Label all the features the same way In the Label Field: Click Expression Label the parcels with their map and parcel ID numbers. Clear the current information in the Expression box. o Highlight and backspace or delete. Change the parser to Python from VB Script. Double click Map to add it to the expression. Next, highlight the PID in blue by left clicking once. Then click the Append button. Page 33

35 The Append button uses the correct syntax to label your fields based upon multiple fields. What is the syntax (expression) used to label this field? Click Verify This opens an expression verification window through which you can also see a sample of your label. Click OK. Return to your expression, and add a, between the quotations so it reads:, Click OK Change the Text Symbol to: o Calibri, white, 10pt font, bold o (use black if you are not using a basemap) Click Apply. Click OK. Use the selection tool to select Parcels: o 124, 130, 131, 132. o Draw a box to select multiple parcels at a time. Take a few minutes to explore the selection tool. At this point, you ve probably selected multiple parcels but maybe you ve also selected points, building footprints, and roads. To only select feature from a particular layer(s) you can Set Selectable Layers in your Table of Contents. 34 P a g e

36 The example on the left shows there are 4 empty parcels selected, 3 roads, 2 foot prints, 1 building, and 1 subdivision. (Yours may look somewhat different.) To clear some of these selections you can click the clear selected features button based on the layer. The layers can be made selectable by toggling the layer off and on Make the following layers un-selectable by clicking this button: o Roads_DOT_newspc o Newspace_addresses o Newspace_buildings o Newspc_SubDiv o Newspace_footprints Page 35

37 The only selectable layer should be your empty_parcels dataset. Save your MXD Activity 2.4: Complex Definition Queries (Optional Activity) Asking the data to meet more than one criteria Open the select by attribute window for the empty_parcels Layers. Look for parcels that are greater than 3000ft 2, and are designated either residential or green space. This can be accomplished with one query rather than with multiple steps as before. In order to be selectable a feature must meet three criteria. To require two criteria use the AND operator. To accommodate for one or another, use the OR operator. Try to build your own equation to meet the criteria: o o o Parcels greater than 3000ft 2 in area AND Parcels designated as Green space OR Parcels designated as residential space o Be sure to put the land use categories in parenthesis () Use the verify button to help you along the way. What equation did you come up with? (There are multiple ways to do this) 36 P a g e

38 How many parcels meet this criteria? Sort the selection descending based upon Shape Area to find the largest parcel. What is the map and PID for the largest parcel that meets our criteria? Optional on your own exercise: add a related table to find out who owns this parcel In the left column, right click in the empty grey space for the largest parcel. Zoom to current feature. Sort the selection ascending to find the smallest parcel. Right click on the parcel and this time choose Pan To. Also try out the Zoom to Highlighted (in yellow), unselect highlighted, and reselect highlighted tools. Page 37

39 Activity 2.5: Summarize a Column and get Statistics (Optional Activity) What is the breakdown of land use classes for our empty parcels? Do the percentages match up with our original parcel dataset? Questions like this can be answered by summarizing a column. Open the attribute table for empty parcels and right click on the LandUse Column. o Be sure to clear selected features from the previous exercise. Choose Summarize. Click Yes to add the table to your map. Select a field to summarize: LandUse Scroll down the list of summary statistics to be included in the output table. Click the plus sign next to Shape_Area Check all of the boxes under Shape_Area Specify output table: o Click on the yellow folder o Navigate to your C:\student\arcgis2\data o Double click the geodatabase, Newspace_Development_area o Name the new table: LandSum o Click OK. Click OK. Which land cover class is the largest? Which is the smallest? 38 P a g e

40 Repeat the Summarize Steps on pages 36 and 37 for the original parcel layer, Newspc_parcels. Name this output table LandSum2 Which land cover class is the largest for all of the parcels? Is this the same as our subset? What is the average size of a single family home in this area? First, set up a definition query to select only single family homes from the Newspace_footprints dataset. o Right click on the layer > Properties > Definition Query o Descript = Single Family o Verify o OK o OK Right click on Shape_Area > Statistics How many houses are single family homes? (The count) What is the minimum square footage? Maximum? What is the average house size? Close ArcMap. Page 39

41 Module 3: Editing Basics Activity 3.1: The Editing Toolbar Open the GF2_Module3_Activities.mxd from C:student\ArcGIS2\Module3_data Go to the main toolbar and select Customize. From the list choose Toolbars > Editor. o Alternatively, you can click the Editor Icon in the main menu. Click the black down arrow to open the pull down menu. Select Start Editing. Click Continue when it warns you that the roads layer is in a different coordinate system. This opens or starts an editing session. The data is not editable (the exceptions being calculating fields and adding fields) outside of an editing session. At the same time, 40 P a g e

42 there are certain tasks, such as sorting the table or adding a field, which cannot be completed while in an editing session. As with all edits, be sure to save often. Saving your edits with Editor is different than the usual CTRL-S. CTRL-S saves your MXD but not your edits. Go back to the Editor toolbar and click on the down arrow again. Always Save Edits before you stop editing. You should always stop editing before moving onto another task. It is easy to accidentally drag or move your data while in an editing session. You can prevent user error by being cautiouss of your editing sessions. In all of the exercises thus far, the area for the Glenmark subdivision has been a large parcel with many houses. This does not accurately reflect the existing tax maps. So the tax map for this area has been georeferenced for you, and uploaded to Arc. This tax map tells us there are many missing parcels for this area, which you probably already knew from comparing the aerial photography to the old parcel dataset. Turn off the Glenmark_parcels and the Morgan_04K_GOOD layers. Turn them back on. Set your selectable layers so that only the Glenmark_parcels are selectable. Open the attribute table for Glenmark_parcels. What is missing from this dataset? Update the parcel number information in the Glenmark_parcels attribute table. o Use the black editor select tool from the editor toolbar to select parcel 118. o With the row selected, in the PID field, type 118. o Editor > Save Edits! Page 41

43 Select parcel 117 and repeat the past 2 steps. Close the attribute table. Open the Attributes from the editing toolbar. Return to the Edit selector and Select parcel 116. Edit the PID in the Table that is now to your right. The map number for this area is 4k. Edit this information in the attribute table as well. SAVE EDITS! Edit attribute information for the rest of the digital parcels in this area to reflect their map and parcel number. When you ve finished be sure to SAVE EDITS and STOP EDITING. 42 P a g e

44 Activity 3.2: Creating New Features Create new features through editing templates. In order to create new features in ArcGIS you must have an established template or place to store the data. This is usually a shapefile or a geodatabase. Editor > Start Editing In the Editor Toolbar, choose Create Features. The create features window will open. Select the Glenmark_parcels template. Your editing template is just the empty dataset which tells Arc the details of the data you are trying to create (polygon, point, feature class, etc.). Once it s selected, construction tools will become available. Another key component to creating and editing data is snapping. Snapping allows you to create features that connect to each other so your edits are more accurate, with fewer errors. When snapping is turned on, your pointer will jump, or snap to, edges, vertices, and other geometric elements when your pointer is near them and within a certain tolerance. This enables you to Page 43

45 position a feature easily in relation to the locations of other features (ArcGIS Resources). Open the Snapping toolbar: o o Customize > Toolbars > Snapping OR you can go to Editor > Snapping > Snapping Toolbar Point Snapping Snaps to point features End Snapping Snaps to the start or end points of lines when editing Vertex Snapping Snaps to the vertices of lines or polygons when editing Edge Snapping Snaps to line or polygon boundaries when editing At this point, all of your snapping elements are turned on. With your create features window up and your snapping turned on, you will now work to fill in the missing parcels from Map 4K. Click on the Polygon construction Tool. Zoom to parcel 142. o There is also a bookmark for parcel 142. Left click once to start digitizing. Left click to continue to place points and lines which will make up your polygon. Follow the borders for parcel 142. Because the southern border follows the road, you made need to make several vertices so that your polygon has the correct shape. Double Click to finish your parcel. o HINT: If you accidentally click off the parcel boundary you can right click while you are digitizing and choose to Delete Sketch or Delete Vertex. If you delete the Sketch you will have to start over. Deleting 44 P a g e

46 the vertex will allow you to replace it with a better location and continue digitizing your map. Open the attribute editor from the Editor Toolbar. Type in the map number and the parcel number in the correct attribute fields. Editor > Save Edits. Clear selected features Next you will collect parcel 147 which shares a border with two parcels already in the dataset. For this task you will use some additional features such as Trace. Auto hide the Attribute editor by clicking the pin. You may find digitizing easier if you turn off all un-needed layers such as newspc_parcels and roads. Re-open the Create Features menu. o Pin it to the right side of your screen. Click the polygon construction tool again. Start with parcel 147 where it shares a border with parcel Select the Trace Tool. Left click once on the line to start the tool. Follow the line down until the adjoining border with parcel 145. Single left click again. Change back to the straight segment tool. Finish collecting the parcel. o You will need to use the trace tool again to make sure your borders match perfectly. Update the attributes. Save Edits! Practice your digitizing by collecting parcels 145, 140, 141, 151, 150, 149 Page 45

47 Optional Activity: If you have extra time, collect the rest of the parcels along Lucas Drive. Activity 3.3: Editing Tools Now that you ve learned to edit attributes and create new features, there are a few other tools available in the editing toolbar. Select parcel(s) 146/146.1 with the Edit Select tool. Notice that this parcel has not been subdivided. To make this change in the dataset, use the cut Polygon tool. Select the Cut Polygon tool. When using the Cut Polygon tool, you must start on one side of the polygon and finish on the other. DO NOT try to match the line, you must literally cut through the polygon. Feel free to extend your line beyond both sides. Left click on the north side of the parcel. Follow the line separating 146 from Left click along the line to establish vertices. When you get to the other side, be sure to clear the boundary line and double click to finish the cut. NOTE: If you create an error, you may use the EDIT > UNDO button or ctrl+z. (You may only undo up until your last save edits.) If you misplace a vertex, right click delete sketch and start again. As with any activity, practice will help your workflow and process. Open the attribute table from the Table of Contents for the Glenmark_Parcels layer. Switch to selected records only. Notice that the new parcel you created automatically assumed the attributes already filled in for the parcel. Editor > Save Edits 46 P a g e

48 Editor > Stop Editing Search Features in ArcGIS The ArcGIS toolset is vast and can be very overwhelming. One way to get simplify all of the options is to use the Search Box. Click on the Search Icon in the main toolbar. A new window will appear to the right. To add the newly digitized parcels to the existing parcel dataset, the append tool will be used. In the Search box type Append. How many items are returned? If you click on any of the Blue links, that specific tool will open. If you click on the Green link, Arc will open the location of the tool in the Toolbox. Click the Append (Data Management) tool (in Blue). When the Append tool opens, click the Show Help button. What does the append tool do? Page 47

49 Return to the search menu. Search for Merge. Then click on the link. What is the main difference between these two tools? Reopen the Append tool if you ve closed it already. With the Help documentation open, click in the space for Input Dataset. Choose the Glenmark_Parcels dataset. With the Help documentation open, click in the space for the Target Dataset. Target Dataset : Newspc_parcels Click OK. Open the attribute table to make sure that all of the parcels have been added. Activity 3.4: Completing the Dataset (If Time Permits) Complete digitizing the parcels if you didn t earlier. Open the attribute table for Newspc_parcels Make sure that as many attributes are filled in as possible, especially for the new sections you appended. 48 P a g e

50 o o o o o Map (4K), District 8, PID, and land use Turn off Morgan_4K_Good to see imagery more clearly. Land use is set up as a domain. So when you are editing you can just choose from the pull down list. Whatever you think is best will work for now, as long as the dataset is complete. District can be calculated with field calculator. Ask your instructor for more details. Page 49

51 Module 4: Basic Analysis Tools and Features The main goals of this course have been to teach you how to compile and interpret some of the many component of a GIS. In this module, the goal is to use multiple analysis techniques to find the optimal location(s) for a park. Activity 4.1: Set-up Project In the following activities, you will create many new datasets. To ensure that your data is stored in the proper location we will change some settings in ArcMap so that all of your data automatically saves to the correct location. Open the mxd, GF2_Module4_Activities Go to Geoprocessing in the main menu. Choose Environments. The Environments window will open. Click on Workspace Folder paths to where the data will default or automatically store will open up. Click the top yellow folder. Go to your C:\student\ArcGIS2\data Select the geodatabase: o Newspace_Development_Analysis 50 P a g e

52 Copy and paste the top line into the second line. o Highlight CTRL+C o Highlight CTRL+V Click OK when you are finished. You may change symbology at this time to your suite your liking. Activity4.2: Find empty lots Step 1: Query out footprints smaller than 1000ft2 Right click on the layer Newspace_footprints > Properties > Definition Query > Query Builder o Shape_Area >= 1000 o Verify o OK o Apply o OK Step 2: Select by location parcels which do not completely contain buildings Select by Location o Select Features from : newpar_update o Source layer: Newspace_footprints o Spatial Selection method: have their centroid in the source layer feature o Apply a search distance of 50 feet Open the attribute table for newpar_update How many features are selected? Page 51

53 Switch the selection within the attribute table. How many features are now selected? Step 3: Extract empty parcels In the Table of Contents, right click on newpar_update Data > Export-Data C:\student\ArcGIS2\Module4_data\Newspace_Development_Analysis o Name: empty_parc2 o Save as type: File and Personal Geodatabase feature classes Save OK Click Yes to add to the map as a layer. Turn off newpar_update layer. Change the symbology for your empty_parc2 layer so that you can see the imagery easily. o Left single click on the symbol in the TOC. Activity 4.3: Clip, Buffer, Intersect foundations for analysis and data management The only roads needed for our analysis are the roads within the three subdivisions. Before we can clip the roads to this area, we need to dissolve the boundaries between the sub-divisions. Step1: Dissolve Subdivisions to a single boundary Make sure ArcToolbox is docked to the right of your screen. Search for Dissolve. Choose Dissolve (Data Management > Generalization) (Graphic on following page) Input features: newspc_subdiv Output features: o Click the yellow folder o Navigate to: C:\student\ArcGIS2\data\Newspace_Development_Analysis.gdb Name the file: Newspace_area o Save Dissolve_Field: DevArea Leave the rest of the defaults Click OK. 52 P a g e

54 Note: if you get confused about what goes where, use the Tool Help (show help) in the right hand window. Step 2: Clip roads layer to Newspace Development Area Open the Search window and Search for the Clip tool. Click on the green link for the Clip Analysis and the Clip Data Management tools. Right click on each of them and choose Item description. Based upon this item description, what is the main difference between these two tools both termed clip? How do you know which one you should use? Use the Clip (Analysis) tool. o Input Features: roads_dot_newspc o Clip Features: newspace_area o Output Feature class: Click on the yellow folder Navigate to the Newspace_Development_Analsysis.gdb Name the file: roads_clip Save as type: feature classes o SAVE Page 53

55 o OK Turn off the roads_dot_nwspc layer. Open the attribute table for the roads_clip layer. How many roads are there in the subdivisions? Step 3: Buffer roads In addition to reducing the number of roads for the final map, it would be nice if the park were not near any dangerous road areas. The next step will be to create a 10ft buffer around roads. Then by intersecting the buffer with parcels, dangerous areas for parks will be produced. Search for the Buffer tool. Open the Buffer (Analysis) Tool o Input Features: roads_clip o Output Feature Class: Click the yellow folder Navigate to the Newspace_Development_Analysis.gdb Name: roads_buffer o Linear Unit: 20 ft. o Side Type: Full o End Type: Round o Dissolve Type: None o OK 54 P a g e

56 Step 4: Intersect parcels and roads_buffer for dangerous areas Search for the Intersect Tool. Choose the Intersect (Analysis) Tool Input features: o roads_buffer o empty_parc2 Output feature class: o Yellow folder o Newspace_Development_Analysis.gdb o danger_areas o SAVE Click OK to run the tool. How many Danger Areas did this generate? Page 55

57 Activity 4.4: Final Analysis Step 1: Find the parcels that don t have a dangerous area in them. You may need to clear selected features. Select by Location o Select features from o Target layer: empty_parc2 o Source layer: danger_areas o Selection method: contain the source layer feature o Uncheck apply a search dist o OK Open the attribute table for empty_parc2 Switch Selection How many features are selected? Step 2: Find the parcels in this selection that have a land use of either residential, green space, or forest Table Options > Select by Attribute Method: Select from current selection Definition: o LandUse = 'FST' OR LandUse = 'GS' OR LandUse = 'RS' Verify Apply Close How many parcels meet the conditions of Step 1 and Step 2? Export these parcels to a new feature dataset call suitable_p o Right click on empty_parc2 o Data > Export Save it in the Newspace_Development_Analsysis geodatabase. Click YES to add the data to the map as a layer. Make the symbology for the suitable_p layer appropriate to see the imagery. Step 3: A park for Newspace Use what you ve learned to eliminate the parcels outside of the Newspace_area. Also, the parcel should be greater than 10,000ft 2 in area. 56 P a g e

58 What steps did you take to complete this part of the analysis? How many parcels meet this new criteria? Relate the ownership table to see if there is an owner who would be amiable to donating or selling the property. Based upon your analysis which parcel would you recommend for building a park? What are the benefits to building a park in this area? Do you think you ve compiled sufficient evidence for the Newspace Development Authority to support your chosen optimal location? Optional Exercise: Map it! If you have time you can use Day 1 Module 4 to make a map of your chosen parcel or demonstrate the final steps of your analysis. Page 57